Adducts formed from primary amines, dicarbonyl derivatives, inorganic oxide hydroxydes and sp.SUP.2.-hybridized carbon allotropes

Abstract

Adducts are described, obtainable from the reaction product of a secondary amine and a diketone, with carbon allotropes in which the carbon is sp.sup.2 hybridized, such as graphene, graphite, fullerene, carbon nanotubes and the like, and an inorganic oxide-hy-droxide. A process for preparing said adducts is also described.

Claims

1. An adduct obtainable from: a) a reaction product of a compound of formula (I) ##STR00030## wherein X is selected from the group consisting of ##STR00031## wherein: R.sub.5 and R.sub.6 are independently selected from the group consisting of hydrogen, C.sub.1-C.sub.18 alkyl, C.sub.2-C.sub.18 linear or branched alkenyl or alkynyl, aryl, C.sub.1-C.sub.22 linear or branched alkyl-aryl, C.sub.2-C.sub.22 linear or branched alkenyl-aryl, C.sub.2-C.sub.22 linear or branched alkynyl-aryl, and heteroaryl; or at least one of R.sub.5 or R.sub.6 is independently ##STR00032## wherein m is chosen from 0, 1, and 2, and n is chosen from integers ranging from 1 to 30, and wherein if only one of R.sub.5 and R.sub.6 is ##STR00033## wherein m is chosen from 0, 1, and 2, and n is chosen from integers ranging from 1 to 30, then the other is selected from the group consisting of hydrogen, C.sub.1-C.sub.18 alkyl, and C.sub.2-C.sub.18 linear or branched alkenyl or alkynyl; or at least one of R.sub.5 and R.sub.6 is: ##STR00034## wherein n is chosen from 0, 1, 2, and 3, and R.sub.7, R.sub.7′, and R.sub.7″ are independently selected from the group consisting of C.sub.1-C.sub.4 alkyl and C.sub.1-C.sub.4 oxygen-alkyl; or at least one of R.sub.5 and R.sub.6 is ##STR00035## wherein n is chosen from integers ranging from 0 to 10; and R.sub.8 and R.sub.8′ are independently selected from the group consisting of hydrogen and C.sub.1-C.sub.4 alkyl; or at least one of R.sub.5 and R.sub.6 is ##STR00036## wherein n is chosen from integers ranging from 1 to 10; or at least one of R.sub.5 and R.sub.6 is ##STR00037## and R.sub.15 is selected from the group consisting of hydrogen, C.sub.1-C.sub.22 linear or branched alkyl, C.sub.2-C.sub.22 linear or branched alkenyl or alkynyl, aryl, C.sub.1-C.sub.22 linear or branched alkyl-aryl, C.sub.2-C.sub.22 linear or branched alkenyl-aryl, C.sub.2-C.sub.22 linear or branched alkynyl-aryl, linear or branched C.sub.2-C.sub.22 acyl-alkyl, linear or branched C.sub.3-C.sub.22 acyl-alkenyl or acyl-alkynyl, acyl-aryl, acyl-alkyl-aryl with linear or branched C.sub.2-C.sub.22 acyl-alkyl, acyl-alkenyl-aryl with linear or branched C.sub.3-C.sub.22 acyl-alkenyl, acyl-alkynyl-aryl with linear or branched C.sub.3-C.sub.22 acyl-alkynyl, and heteroaryl; or at least one of R.sub.5 and R.sub.6 is ##STR00038## and R.sub.19 is selected from the group consisting of hydrogen, C.sub.1-C.sub.22 linear or branched alkyl, C.sub.2-C.sub.22 linear or branched alkenyl or alkynyl, aryl, C.sub.1-C.sub.22 linear or branched alkyl-aryl, C.sub.2-C.sub.22 linear or branched alkenyl-aryl, C.sub.2-C.sub.22 linear or branched alkynyl-aryl, and heteroaryl; R.sub.9 is selected from the group consisting of hydrogen, alkyl, aryl, benzyl, amine, alkylamine, arylamine, benzylamine, and aminoaryl; R.sub.10, R.sub.11, R.sub.12, R.sub.13 and R.sub.14 are independently selected from the group consisting of hydrogen, C.sub.1-C.sub.18 alkyl, C.sub.2-C.sub.18 linear or branched alkenyl or alkynyl, and 1-(4-aminocyclohexyl)methylene; with a compound of formula (II) ##STR00039## wherein n is chosen from integers ranging from 1 to 1000, m is chosen from integers ranging from 1 to 1000, y is chosen from 0 and 1, and z is chosen from 0 and 1; and wherein R.sub.16 is selected from the group consisting of hydrogen and methyl; and R.sub.17 and R.sub.18 are selected from the group consisting of hydrogen, C.sub.2-C.sub.30 linear or branched alkyl, alkenyl or alkynyl, aryl, C.sub.2-C.sub.30 alkyl-aryl, C.sub.2-C.sub.30 linear or branched alkenyl-aryl, C.sub.2-C.sub.30 alkynyl-aryl, and heteroaryl; b) a carbon allotrope with sp.sup.2 hybridized carbon atoms; and c) an inorganic oxide-hydroxide.

2. The adduct according to claim 1, wherein the carbon allotrope with sp.sup.2 hybridized carbon atoms is selected from the group consisting of graphene, nano-graphites consisting of few graphene layers, graphite, fullerene, nanotoroids, nanocones, graphene nanoribbons, single-wall or multi-wall carbon nanotubes, and carbon black.

3. The adduct according to claim 1, wherein the carbon allotrope comprises functional groups selected from the group consisting of: oxygenated functional groups; functional groups containing carbonyls; functional groups containing nitrogen atoms; and functional groups containing sulfur atoms.

4. The adduct according to claim 3, wherein the oxygenated functional groups of the carbon allotrope are chosen from hydroxyls and epoxides.

5. The adduct according to claim 3, wherein the functional groups containing carbonyls of the carbon allotrope are chosen from aldehydes, ketones, and carboxylic acids.

6. The adduct according to claim 3, wherein the functional groups containing nitrogen atoms of the carbon allotrope are chosen from amines, amides, nitriles, diazonium salts, and imines.

7. The adduct according to claim 3, wherein the functional groups containing sulfur atoms of the carbon allotrope are chosen from sulphides, disulfides, mercaptans, sulfones, and sulfinic and sulfonic groups.

8. The adduct according to claim 1, wherein the oxide-hydroxide is selected from the group consisting of silica, layer silicates, fibrillar silicates, mixed oxides of aluminium and magnesium with lamellar structure, and alumina.

9. The adduct according to claim 8, wherein the layer silicates have a thickness of a single layer ranging from 0.1 to 30 nm.

10. The adduct according to claim 9, wherein the thickness ranges from 0.5 to 15 nm, or from 0.8 to 2 nm.

11. The adduct according to claim 9, wherein the layer silicates are selected from the group consisting of serpentine, kaolin, talc, pyrophyllite, smectites, vermiculite, mica, chlorite, palygorskite, sepiolite, allophane, imogolite, and hydrotalcite.

12. The adduct according to claim 11, wherein the layer silicates are smectites chosen from montmorillonite, bentonite, beidellite, nontronite, volkonskoite, hectorite, fluorohectorite, laponite, saponite, stevensite, and sauconite.

13. The adduct according to claim 11, wherein the layer silicates are micas chosen from celadonite, lepidolite, muscovite, and phlogopite.

14. A process for preparing an adduct comprising: reacting a compound of formula (I) with a compound of formula (II) to obtain a compound of formula (III) wherein formula (I) is ##STR00040## wherein X is selected from the group consisting of ##STR00041## wherein: R.sub.5 and R.sub.6 are independently selected from the group consisting of hydrogen, C.sub.1-C.sub.18 alkyl, C.sub.2-C.sub.18 linear or branched alkenyl or alkynyl, aryl, C.sub.1-C.sub.22 linear or branched alkyl-aryl, C.sub.2-C.sub.22 linear or branched alkenyl-aryl, C.sub.2-C.sub.22 linear or branched alkynyl-aryl, and heteroaryl; or at least one of R.sub.5 or R.sub.6 is independently ##STR00042## wherein m is chosen from 0, 1, and 2, and n is chosen from integers ranging from 1 to 30, and wherein if only one of R.sub.5 and R.sub.6 is ##STR00043## wherein m is chosen from 0, 1, and 2, and n is chosen from integers ranging from 1 to 30, then the other is selected from the group consisting of hydrogen, C.sub.1-C.sub.18 alkyl, and C.sub.2-C.sub.18 linear or branched alkenyl or alkynyl; or at least one of R.sub.5 and R.sub.6 is: ##STR00044## wherein n is chosen from 0, 1, 2, and 3, and R.sub.7, R.sub.7′, and R.sub.7″ are independently selected from the group consisting of C.sub.1-C.sub.4 alkyl and C.sub.1-C.sub.4 oxygen-alkyl; or at least one of R.sub.5 and R.sub.6 is ##STR00045## wherein n is chosen from integers ranging from 0 to 10; and R.sub.8 and R.sub.8′ are independently selected from the group consisting of hydrogen and C.sub.1-C.sub.4 alkyl; or at least one of R.sub.5 and R.sub.6 is ##STR00046## wherein n is chosen from integers ranging from 1 to 10; or at least one of R.sub.5 and R.sub.6 is ##STR00047## and R.sub.15 is selected from the group consisting of hydrogen, C.sub.1-C.sub.22 linear or branched alkyl, C.sub.2-C.sub.22 linear or branched alkenyl or alkynyl, aryl, C.sub.1-C.sub.22 linear or branched alkyl-aryl, C.sub.2-C.sub.22 linear or branched alkenyl-aryl, C.sub.2-C.sub.22 linear or branched alkynyl-aryl, linear or branched C.sub.2-C.sub.22 acyl-alkyl, linear or branched C.sub.3-C.sub.22 acyl-alkenyl or acyl-alkynyl, acyl-aryl, acyl-alkyl-aryl with linear or branched C.sub.2-C.sub.22 acyl-alkyl, acyl-alkenyl-aryl with linear or branched C.sub.3-C.sub.22 acyl-alkenyl, acyl-alkynyl-aryl with linear or branched C.sub.3-C.sub.22 acyl-alkynyl, and heteroaryl; or at least one of R.sub.5 and R.sub.6 is ##STR00048## and R.sub.19 is selected from the group consisting of hydrogen, C.sub.1-C.sub.22 linear or branched alkyl, C.sub.2-C.sub.22 linear or branched alkenyl or alkynyl, aryl, C.sub.1-C.sub.22 linear or branched alkyl-aryl, C.sub.2-C.sub.22 linear or branched alkenyl-aryl, C.sub.2-C.sub.22 linear or branched alkynyl-aryl, and heteroaryl; R.sub.9 is selected from the group consisting of hydrogen, alkyl, aryl, benzyl, amine, alkylamine, arylamine, benzylamine, and aminoaryl; R.sub.10, R.sub.11, R.sub.12, R.sub.13 and R.sub.14 are independently selected from the group consisting of hydrogen, C.sub.1-C.sub.18 alkyl, C.sub.2-C.sub.18 linear or branched alkenyl or alkynyl, and 1-(4-aminocyclohexyl)methylene; wherein formula (II) is ##STR00049## wherein n is chosen from integers ranging from 1 to 1000, m is chosen from integers ranging from 1 to 1000, y is chosen from 0 and 1, and z is chosen from 0 and 1; and wherein R.sub.16 is selected from the group consisting of hydrogen and methyl; and R.sub.17 and R.sub.18 are selected from the group consisting of hydrogen, C.sub.2-C.sub.30 linear or branched alkyl, alkenyl or alkynyl, aryl, C.sub.2-C.sub.30 alkyl-aryl, C.sub.2-C.sub.30 linear or branched alkenyl-aryl, C.sub.2-C.sub.30 alkynyl-aryl, and heteroaryl; and and wherein formula (III) is ##STR00050## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are independently selected from the group consisting of hydrogen, C.sub.1-C.sub.3 alkyl, C.sub.2-C.sub.18 linear or branched alkenyl or alkynyl, aryl, C.sub.1-C.sub.18 linear or branched alkyl-aryl, C.sub.2-C.sub.18 linear or branched alkenyl-aryl, C.sub.2-C.sub.22 linear or branched alkynyl-aryl, and heteroaryl; reacting the compound of formula (III) with a carbon allotrope with sp.sup.2 hybridized carbon atoms and an inorganic oxide-hydroxide by providing energy in a form chosen from thermal, mechanical, photon irradiation, and mixtures thereof to a mixture of the reactants in the presence of oxygen.

15. The process according to claim 14, wherein the thermal energy is provided at a temperature ranging from 50° C. to 180° C. and for a time ranging from 15 to 360 minutes.

16. The process according to claim 14, wherein the mechanical energy is provided for a time ranging from 15 to 360 minutes.

17. The process according to claim 14, wherein the photon irradiation energy is provided at a wavelength ranging from 200 to 380 nm and for a time ranging from 30 to 180 minutes.

Description

EXAMPLES

(1) The adducts obtained by the examples presented below were analysed as follows: infrared spectroscopy (FT-IR), using a KBr pellet: adduct/KBr weight ratios of 1:500 were used, and about 80 mg of mixture for forming the pellet. The pellet was analysed with a Fourier transform IR spectrophotometer (Varian 640-IR FT-IR spectrometer with ATR option). The samples were irradiated in a range between 2.5 and 20 μm (or between 4000 and 500 cm.sup.−1). UV spectroscopy: the suspensions of adduct (3 mL) were placed, using a Pasteur pipette, in quartz cuvettes with a 1 cm optical path (volume 1 or 3 mL) and were analysed using a UV-Vis spectrophotometer. The instrument is zeroed with the pure solvent and a UV spectrum is recorded from 200 to 340 nm. A blank of the solvent used was recorded. The UV-visible spectrum gave the intensity of absorption as a function of the wavelength of the radiation between 200 and 750 nm. NMR (nuclear magnetic resonance): This technique was used for confirming the structure of the pyrrole compounds. .sup.1H NMR spectra were recorded at a temperature of 27° C. using a Bruker AV 400 spectrometer operating at 400 MHz (Bruker, Rheinstetten, Germany). The solvents used for performing the analysis were deuterated, deuterated chloroform (CDCl.sub.3) being used in particular.

(2) Extraction Test

(3) This test is intended to verify the stability of the interaction between the carbon allotrope, the organic oxide-hydroxide and the pyrrole compound.

(4) Procedure:

(5) Acetone (100 mL) is poured into a 250-mL single-neck flask equipped with a Soxhlet extractor. A filtering crucible containing powdered adduct (10 g) is put inside the Soxhlet extractor. Continuous extraction is performed at the boiling point of acetone (56° C.) for 12 hours. After this time, the powder is recovered from the extraction crucible and is dried in a stove. An aliquot of the acetone is injected into a gas chromatograph combined with a mass spectrometer Agilent 5973 Network Mass Selective Detector with 6890 Series GC System.

(6) Test of Stability of the Suspension

(7) This test is intended to verify the capacity of the ternary system consisting of the carbon allotrope, the inorganic oxide-hydroxide and the pyrrole compound, for forming suspensions that are stable over time. The stability in solvents was evaluated in a polar medium, water, and in a non-polar medium, toluene.

(8) Procedure, Stability in Water:

(9) 10 mg of powdered adduct was put in a 10-mL flask, and distilled water (10 mL) was added. The mixture was sonicated in a 2-litre ultrasonic bath, with power of 260 W, for 20 minutes.

(10) The suspensions of adduct (3 mL) at a concentration of 1 mg/mL were transferred, using a Pasteur pipette, to quartz cuvettes with a 1 cm optical path (volume 1 or 3 mL) and were analysed using a UV-Vis spectrophotometer. The instrument was zeroed beforehand with pure solvent, recording a UV spectrum (200-340 nm). The UV-visible spectrum gave the intensity of absorption as a function of the wavelength of the radiation between 200 and 750 nm.

(11) To evaluate the stability over time of the suspensions obtained, measurement of UV-Vis absorption was then repeated a week later.

(12) Procedure, Stability in Toluene:

(13) 10 mg of powdered adduct was put in a 10-mL flask, and toluene (10 mL) was added. The mixture was sonicated in a 2-litre ultrasonic bath, with power of 260 W for 20 minutes.

(14) The suspensions of adduct (3 mL) at a concentration of 1 mg/mL were transferred, using a Pasteur pipette, to quartz cuvettes with a 1 cm optical path (volume 1 or 3 mL) and were analysed using a UV-Vis spectrophotometer. The instrument was zeroed beforehand with pure solvent, recording a UV spectrum (200-340 nm). The UV-visible spectrum gave the intensity of absorption as a function of the wavelength of the radiation between 200 and 750 nm.

(15) To evaluate the stability over time of the suspensions obtained, measurement of UV-Vis absorption was then repeated a week later.

(16) Tests of Preparation of the Adducts

(17) Tables 1A and 1B present the tests carried out for preparation of the adducts. The ingredients for preparing the adducts are: amine (A), diketone (B), carbon allotrope (C), inorganic oxide-hydroxide (D), pyrrole compound (P).

(18) TABLE-US-00001 TABLE 1A Tests of preparation of the adducts Substances Inorganic mixed Pyrrole Carbon oxide (A) (B) compound allotrope hydroxide Ex. Amine Diketone (P) (C) (D) 1 inv Serinol 2,5-ED 0 CB N326 SiO.sub.2 2 inv Serinol 2,5-ED 0 CB N326 SiO.sub.2 3 inv Serinol 2,5-ED 0 CB N326 SiO.sub.2 4 inv Serinol 2,5-ED 0 CB N326 Mt 5 inv Hexanamine 2,5-ED 0 CB N326 SiO.sub.2 6 inv APTES 2,5-ED 0 CB N326 SiO.sub.2 7 cmp Serinol 2,5-ED 0 = SiO.sub.2 8 cmp = 2,5-ED 0 CB N326 SiO.sub.2 9 cmp Serinol = 0 CB N326 SiO.sub.2 10 cmp Serinol 2,5-ED 0 CB N326 = 11 inv = = Hexyl CB N326 SiO.sub.2 pyrrole 12 inv = = Hexyl graphite SiO.sub.2 pyrrole 13 inv = = Trimethyl CB N326 SiO.sub.2 pyrrole 14 inv = = Trimethyl graphite SiO.sub.2 pyrrole 15 inv Serinol 2,5-ED 0 CB N326 SiO.sub.2 16 inv Hexanamine 2,5-ED 0 CB N326 SiO.sub.2 17 inv Serinol 2,5-ED 0 CB N326 SiO.sub.2 18 inv Hexanamine 2,5-ED 0 CB N326 SiO.sub.2 19 inv Serinol 2,5-ED 0 CB N326 SiO.sub.2 20 inv Hexanamine 2,5-ED 0 CB N326 SiO.sub.2 2,5-ED = 2,5-hexanedione; SiO.sub.2 = Zeosil 1165 MP (Rhodia)

(19) TABLE-US-00002 TABLE 1B Tests of preparation of the adducts Molar Molar Weight Molar Weight Weight ratio ratio ratio ratio ratio ratio Ex. A/B (A)/(C) (A + B)/(C) (P)/(C) (P)/(C) (C)/(D Proc.  1 inv 1:1 1:10 1/3.51 = = 1:1 1  2 inv 1:1 1:10 1/3.51 = = 2:1 1  3 inv 1:1 1:10 1/3.51 = = 4:1 1  4 inv 1:1 1:10 1/3.51 = = 1:1 1  5 inv 1:1 1:10 1/2.1  = = 1:1 1  6 inv 1:1 1:10 1/1.35 = = 1:1 1  7 cmp 1:1 = = = 0  8 cmp 0 0 1/6.31 = = 1:1  9 cmp = 1:10 1/7.91 = = 1:1 10 cmp 1:1 1:10 1/3.51 = = = 1 11 inv = 0 = 1:10 1:4.03 1:1 9 12 inv = 0 = 1:10 1:4.03 1:1 9 13 inv = 0 = 1:10 1:6.60 1:1 9 14 inv = 0 = 1:10 1:6.60 1:1 9 15 inv 1:1 1:10 1/3.51 = = 1:1 2 16 inv 1:1 1:10 1/2.1  = = 1:1 2 17 inv 1:1 1:10 1/3.51 = = 1:1 5 18 inv 1:1 1:10 1/2.1  = = 1:1 5 19 inv 1:1 1:10 1/3.51 = = 1:1 6 20 inv 1:1 1:10 1/2.1  = = 1:1 6

(20) The adducts according to the present invention were prepared starting from:

(21) (i) amine, diketone, carbon allotrope, inorganic oxide-hydroxide: examples 1, 2, 3, 4, 5, 6, 15, 16, 17, 18, 19, 20;

(22) (ii) pyrrole compound, carbon allotrope, inorganic oxide-hydroxide: examples 11, 12, 13, 14.

(23) In examples 1, 2, 3, 4, 5 and 6, the carbon allotrope is firstly pre-dispersed in an environmentally friendly low-boiling solvent such as acetone and then the amine, diketone and silica are added to this dispersion. The solvent is then removed and the powder obtained is then heated. Further details are given in the description of the examples.

(24) In examples 1, 2 and 3, the adduct is formed from serinol, 2,5-hexanedione, carbon black and silica. The molar ratio between serinol and hexanedione (molar ratio A/B) is the stoichiometric ratio for the Paal-Knorr reaction. The molar ratio between serinol and the carbon allotrope (molar ratio A/C) is equal to 1/10. This molar ratio indicates the ratio between serinol and the benzene ring, regarded as the constituent unit of the allotrope. It is thus a calculated ratio. Table 1 also gives the weight ratio between the sum of amine and diketone and the carbon allotrope. This is a primary experimental value, since all the substances are weighed.

(25) Table 1 also gives the weight ratio between the carbon allotrope and silica. Silica in fact has a dual function: it performs the role of catalyst for the reaction of the amine with the diketone and thus allows formation of the pyrrole compound even at low temperature and prevents extractability of the organic substances that form the adduct, from said adduct.

(26) In example 4, the inorganic oxide-hydroxide consists of montmorillonite. The other components of the adduct remain unchanged. A 1:1 ratio of carbon black to montmorillonite was adopted.

(27) In example 5, hexanamine was used as the amine. The different value of the weight ratio (A+B)/(C) is only due to the different molar mass of the hexanamine.

(28) In example 6, (3-aminopropyl)triethoxysilane was used as the amine. In this case too, the different value of the weight ratio (A+B)/(C) is only due to the different molar mass of the silane, relative to the amines used in the previous examples. A 1:1 ratio of carbon black to silica was adopted.

(29) Examples 7, 8, 9 and 10 constitute comparative examples of the present invention. Each of these lacks one component of the adduct of the present invention. In example 7, no carbon allotrope was used. In example 8, no amine was used, in example 9, no diketone was used, and in example 10, no inorganic oxide-hydroxide was used. Mixing of the components was carried out according to the same experimental procedure as in examples 1-6, obviously taking into account the absence of one of the components of the adduct.

(30) In examples 11, 12, 13 and 14 of the present invention, the adduct is formed by bringing a pyrrole compound, a carbon allotrope and silica into contact. The experimental procedure is the same as that followed for examples 1-6, with the substantial difference that instead of adding amine, diketone and silica to the suspension of the allotrope in acetone, the pyrrole compound and silica are added. In examples 11 and 12, the pyrrole compound used was a compound called N-hexylpyrrole, prepared by reaction of hexanamine with 2,5-diketone. In examples 13 and 14, trimethyl pyrrole was used—a compound that is available commercially. In examples 11 and 13, the carbon allotrope used was carbon black. In examples 12 and 14, the carbon allotrope used was a high surface area graphite, of nanometric dimensions.

(31) In examples 15, 16, 17, 18, 19, and 20, amine, diketone, carbon allotrope and inorganic oxide-hydroxide were used for preparing the adduct according to the present invention. In all these examples the carbon allotrope was carbon black, and the inorganic oxide-hydroxide was silica. In examples 15, 17 and 19 the amine was serinol, in examples 16, 18 and 20, the amine was hexanamine. The ratios of the components adopted are, for serinol, equal in examples 15, 17 and 19 and are also equal to those adopted in example 1. The ratios of the components adopted are, for hexanamine, equal in examples 16, 18 and 20 and are also equal to those adopted in example 5. In examples 15-20, the experimental procedures for preparing the adduct were modified relative to example 1 and example 5. In examples 15 and 16, the amine and the diketone were premixed in the same solvent used for preparing the suspension of the allotrope. Both silica and the solution of amine and diketone in acetone were added to the suspension of the allotrope in acetone. From here, the procedure was the same as that adopted for example 1 and example 5.

(32) In examples 17 and 18, the amine and the diketone were premixed with silica in an environmentally friendly low-boiling solvent such as acetone. This solvent was then removed and a powder was obtained, which was then heated. The powder was then mixed in the solid state with the carbon allotrope. From here, the procedure is the same as that adopted for examples 1 and 5.

(33) In examples 19 and 20, the amine and the diketone were premixed with silica in the solid state. The powder was heated and was then mixed in the solid state with the carbon allotrope. From here, the procedure is the same as that adopted for examples 1 and 5.

Example 1

Invention

(34) Adduct of 2-amino-1,3-propanediol (serinol), 2,5-hexanedione with carbon black and silica (carbon black/silica ratios 1/1 by weight).

(35) The carbon black used is Carbon Black N326 (CB) (Cabot), with the following characteristics: 30 nm average diameter of the spherical particles, surface area equal to 77 m.sup.2/g (determined by nitrogen absorption), absorption of DBP equal to 85 mL/100 g. The silica used is Zeosil 1165 MP (Rhodia). The serinol used is Bracco and the 2,5-hexanedione was acquired from Aldrich.

(36) A 100-mL single-neck flask is charged with 2.5 g of carbon black and 15 mL of acetone. The suspension is sonicated in an ultrasonic bath for 15 minutes. After this time, the following are added successively: 0.316 g of serinol, 0.396 g of 2,5-hexanedione and silica (2.5 g). The resultant suspension is sonicated for 15 minutes. The solvent is removed at reduced pressure. A powder is obtained, consisting of serinol and 2,5-hexanedione absorbed on the mixture of carbon black and silica.

(37) The powder is put in a 100-mL flask equipped with a magnetic stirrer and is heated at a temperature of 180° C. for 2 hours. After this time, the powder is cooled to 25° C.

(38) A suspension in water was prepared with the sample of treated carbon black after heating at 180° C. for 2 hours. The suspension, having a concentration equal to 1 mg/mL, was sonicated for 10 minutes and was analysed by ultraviolet (UV) spectroscopy. UV spectra were recorded immediately after sonication and after 24 hours and they showed the same absorbance.

Example 2

Invention

(39) Adduct of 2-amino-1,3-propanediol (serinol), 2,5-hexanedione with carbon black and silica (carbon black/silica ratios 2/1 by weight).

(40) The carbon black used is Carbon Black N326 (CB) (Cabot), with the following characteristics: 30 nm average diameter of the spherical particles, surface area equal to 77 m.sup.2/g (determined by nitrogen absorption), absorption of DBP equal to 85 mL/100 g. The silica used is Zeosil 1165 MP (Rhodia). The serinol used is Bracco and the 2,5-hexanedione was acquired from Aldrich.

(41) A 100-mL single-neck flask is charged with 3.33 g of carbon black and 15 mL of acetone. The suspension is sonicated in an ultrasonic bath for 15 minutes. After this time, the following are added successively: 0.421 g of serinol, 0.527 g of 2,5-hexanedione and silica (1.67 g). The resultant suspension is sonicated for 15 minutes. The solvent is removed at reduced pressure. A powder is obtained, consisting of serinol and 2,5-hexanedione absorbed on the mixture of carbon black and silica.

(42) The powder is put in a 100-mL flask equipped with a magnetic stirrer and is heated at a temperature of 180° C. for 2 hours. After this time, the powder is cooled to 25° C.

(43) A suspension in water was prepared with the sample of treated carbon black after heating at 180° C. for 2 hours. The suspension, having a concentration equal to 1 mg/mL, was sonicated for 10 minutes and was analysed by ultraviolet (UV) spectroscopy. UV spectra were recorded immediately after sonication and after 24 hours and they showed the same absorbance.

Example 3

Invention

(44) Adduct of 2-amino-1,3-propanediol (serinol), 2,5-hexanedione with carbon black and silica (carbon black/silica ratios 4/1 by weight).

(45) The carbon black used is Carbon Black N326 (CB) (Cabot), with the following characteristics: 30 nm average diameter of the spherical particles, surface area equal to 77 m.sup.2/g (determined by nitrogen absorption), absorption of DBP equal to 85 mL/100 g. The silica used is Zeosil 1165 MP (Rhodia). The serinol used is Bracco and the 2,5-hexanedione was acquired from Aldrich.

(46) A 100-mL single-neck flask is charged with 4 g of carbon black and 15 mL of acetone. The suspension is sonicated in an ultrasonic bath for 15 minutes. After this time, the following are added successively: 0.506 g of serinol, 0.630 g of 2,5-hexanedione and silica (1 g). The resultant suspension is sonicated for 15 minutes. The solvent is removed at reduced pressure. A powder is obtained, consisting of serinol and 2,5-hexanedione absorbed on the mixture of carbon black and silica.

(47) The powder is put in a 100-mL flask equipped with a magnetic stirrer and is heated at a temperature of 180° C. for 2 hours. After this time, the powder is cooled to 25° C.

Example 4

Invention

(48) In this example, Dellite was used instead of silica.

(49) Adduct of 2-amino-1,3-propanediol (serinol), 2,5-hexanedione with carbon black and Dellite (carbon black/Dellite ratios 1/1 by weight).

(50) The carbon black used is Carbon Black N326 (CB) (Cabot), with the following characteristics: 30 nm average diameter of the spherical particles, surface area equal to 77 m.sup.2/g (determined by nitrogen absorption), absorption of DBP equal to 85 mL/100 g. The serinol is Bracco. The 2,5-hexanedione is from Aldrich.

(51) A 100-mL single-neck flask is charged with 2.5 g of carbon black and 15 mL of acetone. The suspension is sonicated in an ultrasonic bath for 15 minutes. After this time, the following are added successively: 0.316 g of serinol, 0.396 g of 2,5-hexanedione and Dellite (2.5 g). The resultant suspension is mixed and sonicated for 15 minutes. The solvent is removed at reduced pressure. A powder is obtained, consisting of serinol and 2,5-hexanedione absorbed on the mixture of carbon black and Dellite.

(52) The powder is put in a 100-mL flask equipped with a magnetic stirrer and is heated at a temperature of 180° C. for 2 hours. After this time, the powder is cooled to 25° C.

Example 5

Invention

(53) Adduct of hexanamine, 2,5-hexanedione with carbon black and silica (carbon black/silica ratios 1/1 by weight).

(54) The carbon black used is Carbon Black N326 (CB) (Cabot), with the following characteristics: 30 nm average diameter of the spherical particles, surface area equal to 77 m.sup.2/g (determined by nitrogen absorption), absorption of DBP equal to 85 mL/100 g. The silica used is Zeosil 1165 MP (Rhodia). The hexanamine and 2,5-hexanedione were acquired from Aldrich.

(55) A 100-mL single-neck flask is charged with 2.5 g of carbon black and 15 mL of acetone. The suspension is sonicated in an ultrasonic bath for 15 minutes. After this time, the following are added successively: 0.558 g of hexanamine, 0.630 g of 2,5-hexanedione and silica (2.5 g). The resultant suspension is sonicated for 15 minutes. The solvent is removed at reduced pressure. A powder is obtained, consisting of hexanamine and 2,5-hexanedione absorbed on the mixture of carbon black and silica.

(56) The powder is put in a 100-mL flask equipped with a magnetic stirrer and is heated at a temperature of 180° C. for 2 hours. After this time, the powder is cooled to 25° C.

Example 6

Invention

(57) Adduct of 3-aminopropyltriethoxysilane, 2,5-hexanedione with carbon black and silica (carbon black/silica ratios 1/1 by weight).

(58) The carbon black used is Carbon Black N326 (CB) (Cabot), with the following characteristics: 30 nm average diameter of the spherical particles, surface area equal to 77 m.sup.2/g (determined by nitrogen absorption), absorption of DBP equal to 85 mL/100 g. The silica used is Zeosil 1165 MP (Rhodia). The 3-am inopropyltriethoxysilane and 2,5-hexanedione were acquired from Aldrich.

(59) A 100-mL single-neck flask is charged with 2.5 g of carbon black and 15 mL of acetone. The suspension is sonicated in an ultrasonic bath for 15 minutes. After this time, the following are added successively: 1.22 g of 3-aminopropyltriethoxysilane, 0.630 g of 2,5-hexanedione and silica (2.5 g). The resultant suspension is sonicated for 15 minutes. The solvent is removed at reduced pressure. A powder is obtained, consisting of 3-aminopropyltriethoxysilane and 2,5-hexanedione absorbed on the mixture of carbon black and silica.

(60) The powder is put in a 100-mL flask equipped with a magnetic stirrer and is heated at a temperature of 180° C. for 2 hours. After this time, the powder is cooled to 25° C.

Example 7

Comparison

(61) Only silica was used in this example (no carbon allotrope).

(62) Adduct of 2-amino-1,3-propanediol (serinol), 2,5-hexanedione with silica. Synthesis of 2-(2,5-dimethyl-1H-pyrrol-1-yl)propane-1,3-diol.

(63) The silica used is Zeosil 1165 MP (Rhodia). The serinol is Bracco and the 2,5-hexanedione is from Aldrich.

(64) A 50-mL single-neck flask is charged with 1 g of silica and successively 0.082 g of serinol and 0.104 g of 2,5-hexanedione. The mixture is first sonicated (15 minutes) and then is stirred at 25° C. for a week. After this time a portion is removed, filtered on a Büchner using D.sub.2O and analysed by .sup.1H NMR analysis. The spectrum revealed the presence of 2-(2,5-dimethyl-1H-pyrrol-1-yl)propane-1,3-diol.

Example 8

Comparison

(65) Silica, carbon black and the dicarbonyl compound were used in this example (no primary amine).

(66) Adduct of 2,5-hexanedione with carbon black and silica (carbon black/silica ratios 1/1 by weight).

(67) The carbon black used is Carbon Black N326 (CB) (Cabot), with the following characteristics: 30 nm average diameter of the spherical particles, surface area equal to 77 m.sup.2/g (determined by nitrogen absorption), absorption of DBP equal to 85 mL/100 g. The silica used is Zeosil 1165 MP (Rhodia). The 2,5-hexanedione was acquired from Aldrich.

(68) A 100-mL single-neck flask is charged with 2.5 g of carbon black and 15 mL of acetone. The suspension is sonicated in an ultrasonic bath for 15 minutes. After this time, the following are added successively: 0.396 g of 2,5-hexanedione and silica (2.5 g). The resultant suspension is sonicated for 15 minutes. The solvent is removed at reduced pressure. A powder is obtained, consisting of 2,5-hexanedione absorbed on the mixture of carbon black and silica.

(69) The powder is put in a 100-mL flask equipped with a magnetic stirrer and is heated at a temperature of 180° C. for 2 hours. After this time, the powder is cooled to 25° C.

Example 9

Comparison

(70) Silica, carbon black and a primary amine (serinol) were used in this example (no dicarbonyl compound).

(71) Adduct of serinol with carbon black and silica (carbon black/silica ratios 1/1 by weight).

(72) The carbon black used is Carbon Black N326 (CB) (Cabot), with the following characteristics: 30 nm average diameter of the spherical particles, surface area equal to 77 m.sup.2/g (determined by nitrogen absorption), absorption of DBP equal to 85 mL/100 g. The silica used is Zeosil 1165 MP (Rhodia). The serinol used is Bracco.

(73) A 100-mL single-neck flask is charged with 2.5 g of carbon black and 15 mL of acetone. The suspension is sonicated in an ultrasonic bath for 15 minutes. After this time, the following are added successively: 0.316 g of serinol and silica (2.5 g). The resultant suspension is sonicated for 15 minutes. The solvent is removed at reduced pressure. A powder is obtained, consisting of serinol absorbed on the mixture of carbon black and silica.

(74) The powder is put in a 100-mL flask equipped with a magnetic stirrer and is heated at a temperature of 180° C. for 2 hours. After this time, the powder is cooled to 25° C.

Example 10

Comparison

(75) Adduct of 2-amino-1,3-propanediol (serinol), 2,5-hexanedione with carbon black.

(76) The carbon black used is Carbon Black N326 (CB) (Cabot), with the following characteristics: 30 nm average diameter of the spherical particles, surface area equal to 77 m.sup.2/g (determined by nitrogen absorption), absorption of DBP equal to 85 mL/100 g. The serinol used is Bracco and the 2,5-hexanedione was acquired from Aldrich.

(77) A 100-mL single-neck flask is charged with 2.5 g of carbon black and 15 mL of acetone. The suspension is sonicated in an ultrasonic bath for 15 minutes. After this time, the following are added successively: 0.316 g of serinol and 0.396 g of 2,5-hexanedione. The resultant suspension is sonicated for 15 minutes. The solvent is removed at reduced pressure. A powder is obtained, consisting of serinol and 2,5-hexanedione, absorbed on the carbon black.

(78) The powder is put in a 100-mL flask equipped with a magnetic stirrer and is heated at a temperature of 180° C. for 2 hours. After this time, the powder is cooled to 25° C.

(79) A suspension in water was prepared with the sample of treated carbon black after heating at 180° C. for 2 hours. The suspension, having a concentration equal to 1 mg/mL, was sonicated for 10 minutes and was analysed by ultraviolet (UV) spectroscopy. UV spectra were recorded immediately after sonication and after 24 hours and they showed the same absorbance.

Example 11

Invention

(80) Pyrrole, N-hexyl-2,5-dimethylpyrrole synthesized by mixing hexanamine with 2,5-hexanedione at 150° C. for 1 hour, silica and carbon black were used in this example.

(81) Adduct of N-hexyl-2,5-dimethylpyrrole with carbon black and silica (carbon black/silica ratios 1/1 by weight).

(82) The carbon black used is Carbon Black N326 (CB) (Cabot), with the following characteristics: 30 nm average diameter of the spherical particles, surface area equal to 77 m.sup.2/g (determined by nitrogen absorption), absorption of DBP equal to 85 mL/100 g. The silica used is Zeosil 1165 MP (Rhodia). The serinol used is Bracco and the 2,5-hexanedione was acquired from Aldrich.

(83) A 100-mL single-neck flask is charged with 1 g of carbon black and 15 mL of acetone. The suspension is sonicated in an ultrasonic bath for 15 minutes. After this time, the following are added successively: 0.248 g of N-hexyl-2,5-dimethylpyrrole and silica (1 g). The resultant suspension is sonicated for 15 minutes. The solvent is removed at reduced pressure. A powder is obtained, consisting of N-hexyl-2,5-dimethylpyrrole absorbed on the mixture of carbon black and silica.

(84) The powder is put in a 100-mL flask equipped with a magnetic stirrer and is heated at a temperature of 180° C. for 2 hours. After this time, the powder is cooled to 25° C.

Example 12

Invention

(85) In this example the pyrrole, N-hexyl-2,5-dimethylpyrrole, synthesized by mixing hexanamine with 2,5-hexanedione at 150° C. for 1 hour, silica and a high surface area graphite (HSAG) were used.

(86) Adduct of N-hexyl-2,5-dimethylpyrrole with HSAG and silica (HSAG/silica ratios 1/1 by weight).

(87) The graphite used is Synthetic Graphite 8427, acquired from Asbury Graphite Mills Inc., with a minimum carbon content of 99.8 wt. % and a surface area of 330 m.sup.2/g. The silica used is Zeosil 1165 MP (Rhodia). The hexanamine and 2,5-hexanedione were acquired from Aldrich.

(88) A 100-mL single-neck flask is charged with 1 g of HSAG and 15 mL of acetone. The suspension is sonicated in an ultrasonic bath for 15 minutes. After this time, the following are added successively: 0.248 g of N-hexyl-2,5-dimethylpyrrole and silica (1 g). The resultant suspension is sonicated for 15 minutes. The solvent is removed at reduced pressure. A powder is obtained, consisting of N-hexyl-2,5-dimethylpyrrole absorbed on the mixture of HSAG and silica.

(89) The powder is put in a 100-mL flask equipped with a magnetic stirrer and is heated at a temperature of 180° C. for 2 hours. After this time, the powder is cooled to 25° C.

Example 13

Invention

(90) A pyrrole acquired from Aldrich, 1,2,5-trimethylpyrrole, silica and carbon black were used in this example.

(91) Adduct of 1,2,5-trimethylpyrrole with carbon black and silica (carbon black/silica ratios 1/1 by weight).

(92) The carbon black used is Carbon Black N326 (CB) (Cabot), with the following characteristics: 30 nm average diameter of the spherical particles, surface area equal to 77 m.sup.2/g (determined by nitrogen absorption), absorption of DBP equal to 85 mL/100 g. The silica used is Zeosil 1165 MP (Rhodia).

(93) A 100-mL single-neck flask is charged with 1 g of carbon black and 15 mL of acetone. The suspension is sonicated in an ultrasonic bath for 15 minutes. After this time, the following are added successively: 0.188 g of 1,2,5-trimethylpyrrole and silica (1 g). The resultant suspension is sonicated for 15 minutes. The solvent is removed at reduced pressure. A powder is obtained, consisting of 1,2,5-trimethylpyrrole absorbed on the mixture of carbon black and silica.

(94) The powder is put in a 100-mL flask equipped with a magnetic stirrer and is heated at a temperature of 180° C. for 2 hours. After this time, the powder is cooled to 25° C.

Example 14

Invention

(95) A pyrrole acquired from Aldrich, 1,2,5-trimethylpyrrole, silica and a high surface area graphite (HSAG) were used in this example.

(96) Adduct of 1,2,5-trimethylpyrrole with HSAG and silica (HSAG/silica ratios 1/1 by weight).

(97) The graphite used is Synthetic Graphite 8427, acquired from Asbury Graphite Mills Inc., with a minimum carbon content of 99.8 wt. % and a surface area of 330 m.sup.2/g. The silica used is Zeosil 1165 MP (Rhodia). The 1,2,5-trimethylpyrrole was acquired from Aldrich.

(98) A 100-mL single-neck flask is charged with 1 g of HSAG and 15 mL of acetone. The suspension is sonicated in an ultrasonic bath for 15 minutes. After this time, the following are added successively: 0.188 g of 1,2,5-trimethylpyrrole and silica (1 g). The resultant suspension is sonicated for 15 minutes. The solvent is removed at reduced pressure. A powder is obtained, consisting of 1,2,5-trimethylpyrrole absorbed on the mixture of HSAG and silica.

(99) The powder is put in a 100-mL flask equipped with a magnetic stirrer and is heated at a temperature of 180° C. for 2 hours. After this time, the powder is cooled to 25° C.

Example 15

Invention

(100) Adduct of 2-amino-1,3-propanediol (serinol), 2,5-hexanedione with carbon black and silica (carbon black/silica ratios 1/1 by weight).

(101) The carbon black used is Carbon Black N326 (CB) (Cabot), with the following characteristics: 30 nm average diameter of the spherical particles, surface area equal to 77 m.sup.2/g (determined by nitrogen absorption), absorption of DBP equal to 85 mL/100 g. The silica used is Zeosil 1165 MP (Rhodia). The serinol used is Bracco and the 2,5-hexanedione was acquired from Aldrich.

(102) A 100-mL single-neck flask equipped with a magnetic stirrer is charged with 0.316 g of serinol, 0.396 g of 2,5-hexanedione and 10 mL of acetone. A suspension of 2.5 g of carbon black and 2.5 g of silica in 15 mL of acetone is added to the mixture. The suspension is sonicated in an ultrasonic bath for 15 minutes. The solvent is removed at reduced pressure. A powder is obtained, consisting of serinol and 2,5-hexanedione absorbed on the mixture of carbon black and silica.

(103) The powder is put in a 100-mL flask equipped with a magnetic stirrer and is heated at a temperature of 180° C. for 2 hours. After this time, the powder is cooled to 25° C.

(104) A suspension in water was prepared with the sample of treated carbon black after heating at 180° C. for 2 hours. The suspension, having a concentration equal to 1 mg/mL, was sonicated for 10 minutes and was analysed by ultraviolet (UV) spectroscopy. UV spectra were recorded immediately after sonication and after 24 hours and they showed the same absorbance.

Example 16

Invention

(105) Adduct of hexanamine, 2,5-hexanedione with carbon black and silica (carbon black/silica ratios 1/1 by weight).

(106) The carbon black used is Carbon Black N326 (CB) (Cabot), with the following characteristics: 30 nm average diameter of the spherical particles, surface area equal to 77 m.sup.2/g (determined by nitrogen absorption), absorption of DBP equal to 85 mL/100 g. The silica used is Zeosil 1165 MP (Rhodia). Hexanamine and 2,5-hexanedione were acquired from Aldrich. A 100-mL single-neck flask equipped with a magnetic stirrer is charged with 0.558 g of hexanamine, 0.630 g of 2,5-hexanedione and 10 mL of acetone. A suspension of 2.5 g of carbon black and 2.5 g of silica in 15 mL of acetone is added to the mixture. The suspension is sonicated in an ultrasonic bath for 15 minutes. The solvent is removed at reduced pressure. A powder is obtained, consisting of hexanamine and 2,5-hexanedione absorbed on the mixture of carbon black and silica.

(107) The powder is put in a 100-mL flask equipped with a magnetic stirrer and is heated at a temperature of 180° C. for 2 hours. After this time, the powder is cooled to 25° C.

Example 17

Invention

(108) Adduct of 2-amino-1,3-propanediol (serinol), 2,5-hexanedione with carbon black and silica (carbon black/silica ratios 1/1 by weight).

(109) The carbon black used is Carbon Black N326 (CB) (Cabot), with the following characteristics: 30 nm average diameter of the spherical particles, surface area equal to 77 m.sup.2/g (determined by nitrogen absorption), absorption of DBP equal to 85 mL/100 g. The silica used is Zeosil 1165 MP (Rhodia). The serinol used is Bracco and the 2,5-hexanedione was acquired from Aldrich.

(110) A 100-mL single-neck flask equipped with a magnetic stirrer is charged with 0.316 g of serinol, 0.396 g of 2,5-hexanedione, 2.5 g of silica and 10 mL of acetone. The mixture is first stirred at room temperature, and then is dried at reduced pressure. 2.5 g of carbon black is added to the powder thus obtained and it is stirred at 180° C. for 2 hours. After this time, the powder is cooled to 25° C.

(111) A suspension in water was prepared with the sample of treated carbon black after heating at 180° C. for 2 hours. The suspension, having a concentration equal to 1 mg/mL, was sonicated for 10 minutes and was analysed by ultraviolet (UV) spectroscopy. UV spectra were recorded immediately after sonication and after 24 hours and they showed the same absorbance.

Example 18

Invention

(112) Adduct of hexanamine, 2,5-hexanedione with carbon black and silica (carbon black/silica ratios 1/1 by weight).

(113) The carbon black used is Carbon Black N326 (CB) (Cabot), with the following characteristics: 30 nm average diameter of the spherical particles, surface area equal to 77 m.sup.2/g (determined by nitrogen absorption), absorption of DBP equal to 85 mL/100 g. The silica used is Zeosil 1165 MP (Rhodia). The hexanamine and 2,5-hexanedione were acquired from Aldrich.

(114) A 100-mL single-neck flask equipped with a magnetic stirrer is charged with 0.558 g of hexanamine, 0.630 g of 2,5-hexanedione, 2.5 g of silica and 10 mL of acetone. The mixture is first stirred at room temperature, and then is dried at reduced pressure. 2.5 g of carbon black is added to the powder thus obtained and it is stirred at 180° C. for 2 hours. After this time, the powder is cooled to 25° C.

Example 19

Invention

(115) Adduct of 2-amino-1,3-propanediol (serinol), 2,5-hexanedione with carbon black and silica (carbon black/silica ratios 1/1 by weight).

(116) The carbon black used is Carbon Black N326 (CB) (Cabot), with the following characteristics: 30 nm average diameter of the spherical particles, surface area equal to 77 m.sup.2/g (determined by nitrogen absorption), absorption of DBP equal to 85 mL/100 g. The silica used is Zeosil 1165 MP (Rhodia). The serinol used is Bracco and the 2,5-hexanedione was acquired from Aldrich.

(117) A 100-mL single-neck flask equipped with a magnetic stirrer is charged with 0.316 g of serinol, 0.396 g of 2,5-hexanedione, 2.5 g of silica. The mixture is first stirred at room temperature and then is sonicated. 2.5 g of carbon black is added to the powder thus obtained and it is stirred at 180° C. for 2 hours. After this time, the powder is cooled to 25° C.

(118) A suspension in water was prepared with the sample of treated carbon black after heating at 180° C. for 2 hours. The suspension, having a concentration equal to 1 mg/mL, was sonicated for 10 minutes and was analysed by ultraviolet (UV) spectroscopy. UV spectra were recorded immediately after sonication and after 24 hours and they showed the same absorbance.

Example 20

Invention

(119) Adduct of Hexanamine, 2,5-Hexanedione with Carbon Black and Silica (Carbon Black/Silica Ratios 1/1 by Weight).

(120) The carbon black used is Carbon Black N326 (CB) (Cabot), with the following characteristics: 30 nm average diameter of the spherical particles, surface area equal to 77 m.sup.2/g (determined by nitrogen absorption), absorption of DBP equal to 85 mL/100 g. The silica used is Zeosil 1165 MP (Rhodia). The hexanamine and 2,5-hexanedione were acquired from Aldrich.

(121) A 100-mL single-neck flask equipped with a magnetic stirrer is charged with 0.558 g of hexanamine, 0.630 g of 2,5-hexanedione, 2.5 g of silica. The mixture is first stirred at room temperature and then sonicated. 2.5 g of carbon black is added to the powder thus obtained and it is stirred at 180° C. for 2 hours. After this time, the powder is cooled to 25° C.

Example 21

Adduct of 1,2,5-Trimethylpyrrole with HSAG (HSAG/TMP Ratios 6.6/1 by Weight)

(122) A pyrrole acquired from Aldrich, 1,2,5-trimethylpyrrole and a high surface area graphite (HSAG) were used in this example.

(123) The graphite used is Synthetic Graphite 8427, acquired from Asbury Graphite Mills Inc., with a minimum carbon content of 99.8 wt. % and a surface area of 330 m.sup.2/g. The 1,2,5-trimethylpyrrole was acquired from Aldrich.

(124) A 100-mL single-neck flask is charged with 1 g of HSAG (0.014 mol) and 15 mL of acetone. The suspension is sonicated in an ultrasonic bath for 15 minutes. After this time, 0.151 g (0.0014 mol) of 1,2,5-trimethylpyrrole is added. The resultant suspension is sonicated for 15 minutes. The solvent is removed at reduced pressure. A powder is obtained, consisting of 1,2,5-trimethylpyrrole absorbed on HSAG.

(125) The powder is put in a 100-mL flask equipped with a magnetic stirrer and is stirred for 2 hours.

Example 22

Adduct of 1,2,5-trimethylpyrrole with HSAG (HSAG/TMP Ratios 6.6/1 by Weight)

(126) A pyrrole acquired from Aldrich, 1,2,5-trimethylpyrrole and a high surface area graphite (HSAG) were used in this example.

(127) The graphite used is Synthetic Graphite 8427, acquired from Asbury Graphite Mills Inc., with a minimum carbon content of 99.8 wt. % and a surface area of 330 m.sup.2/g. The 1,2,5-trimethylpyrrole was acquired from Aldrich.

(128) A 100-mL single-neck flask is charged with 1 g of HSAG (0.014 mol) and 15 mL of acetone. The suspension is sonicated in an ultrasonic bath for 15 minutes. After this time, 0.151 g (0.0014 mol) of 1,2,5-trimethylpyrrole is added. The resultant suspension is sonicated for 15 minutes. The solvent is removed at reduced pressure. A powder is obtained, consisting of 1,2,5-trimethylpyrrole absorbed on HSAG.

(129) The powder is put in a 100-mL flask equipped with a magnetic stirrer and it is stirred at 180° C. for 2 hours. After this time, the powder is cooled to 25° C.

(130) The adduct that formed was washed in a Soxhlet with acetone for 8 hours. After washing, the powder was recovered and was analysed by infrared spectroscopy.

Example 23

Adduct of 1,2,5-Trimethylpyrrole with HSAG (HSAG/TMP Ratios 0.66/1 by Weight)

(131) A pyrrole acquired from Aldrich, 1,2,5-trimethylpyrrole and a high surface area graphite (HSAG) were used in this example.

(132) The graphite used is Synthetic Graphite 8427, acquired from Asbury Graphite Mills Inc., with a minimum carbon content of 99.8 wt. % and a surface area of 330 m.sup.2/g. The 1,2,5-trimethylpyrrole was acquired from Aldrich.

(133) A 100-mL single-neck flask is charged with 1 g of HSAG (0.014 mol) and 15 mL of acetone. The suspension is sonicated in an ultrasonic bath for 15 minutes. After this time, 1.51 g (0.014 mol) of 1,2,5-trimethylpyrrole is added. The resultant suspension is sonicated for 15 minutes. The solvent is removed at reduced pressure. A powder is obtained, consisting of 1,2,5-trimethylpyrrole absorbed on HSAG.

(134) The powder is put in a 100-mL flask equipped with a magnetic stirrer and it is stirred at 180° C. for 2 hours. After this time, the powder is cooled to 25° C.

(135) The adduct that formed was washed in a Soxhlet with acetone for 8 hours. After washing, the washing acetone was dried at reduced pressure. An amber-coloured oil was isolated, and was analysed by .sup.1H NMR spectroscopy.

Example 24

Adduct of 1,2,5-Trimethylpyrrole with HSAG (HSAG/TMP Ratios 0.0066/1 by Weight)

(136) A pyrrole acquired from Aldrich, 1,2,5-trimethylpyrrole and a high surface area graphite (HSAG) were used in this example.

(137) The graphite used is Synthetic Graphite 8427, acquired from Asbury Graphite Mills Inc., with a minimum carbon content of 99.8 wt. % and a surface area of 330 m.sup.2/g. The 1,2,5-trimethylpyrrole was acquired from Aldrich.

(138) A 50-mL single-neck flask is charged with 0.01 g of HSAG (1.3810.sup.−4 mol) and 5 mL of acetone. The suspension is sonicated in an ultrasonic bath for 15 minutes. After this time, 1.51 g (0.014 mol) of 1,2,5-trimethylpyrrole is added. The resultant suspension is sonicated for 15 minutes. The solvent is removed at reduced pressure. The flask containing the reaction mixture is equipped with a magnetic stirrer. It is stirred at 180° C. for 2 hours. After this time, the reaction mixture is first left to cool to 25° C. and then is dissolved in dichloromethane and then is filtered on a Büchner. The washing dichloromethane is dried at reduced pressure. An amber-coloured oil was isolated, and was analysed by .sup.1H NMR spectroscopy.

Example 25

Invention: Adduct of Serinol Pyrrole with HSAG (HSAG/SP Ratio 10/1 by Weight)

(139) In this example the serinol pyrrole used was synthetized by mixing serinol with 2,5-hexanedione, in equimolar ratio, at 150° C. for 3 hours. The serinol used is from Bracco and 2,5-hexanedione was acquired from Aldrich.

(140) The graphite used is Synthetic Graphite 8427, acquired from Asbury Graphite Mills Inc., with a minimum carbon content of 99.8 wt. % and a surface area of 330 m.sup.2/g.

(141) A 100-mL single-neck flask is charged with 1 g of HSAG and 15 mL of acetone. The suspension is sonicated in an ultrasonic bath for 15 minutes. After this time, 0.100 g of serinol pyrrole are added. The resultant suspension is sonicated for 15 minutes. The solvent is removed at reduced pressure. A powder, consisting of serinol pyrrole on HSAG (HSAG/SP), is obtained. Said powder is heated at 150° C. for 2 hours.

Example 26

Invention: Adduct of Serinol Pyrrole with CBN234 (CBN234/SP Ratio 10/1 by Weight)

(142) In this example the serinol pyrrole used was synthetized by mixing serinol with 2,5-hexanedione, in equimolar ratio, at 150° C. for 3 hours.

(143) The Carbon black (CB) used is Vulcan 7H from Cabot, corresponding to a Carbon Black N234, with a surface area of 113 m.sup.2/g.

(144) A 100-mL single-neck flask is charged with 1 g of CBN234 and 15 mL of acetone. The suspension is sonicated in an ultrasonic bath for 15 minutes. After this time, 0.100 g of serinol pyrrole are added. The resultant suspension is sonicated for 15 minutes. The solvent is removed at reduced pressure. A powder, consisting of serinol pyrrole on CBN234 (CBN234/SP), is obtained. Said powder is heated at 150° C. for 2 hours.

Example 27

Invention: Adduct of Sepiolite and HSAG/SP

(145) In a 100 mL beaker were subsequently introduced: HSAG/SP (1 g), obtained according to example 25, and H.sub.2O (100 mL). The suspension was sonicated for 15 minutes with a probe-type sonicator. After this time, the HSAG/SP suspension in water was poured into a 250 mL beaker, which had been previously charged with 1 g of sepiolite and 100 mL of water. The thus obtained suspension, containing HSAG/SP and sepiolite in water, was left stirring for 30 minutes at room temperature and then at 50° C. for 30 minutes. After this time, the mixture is centrifuged at 9000 rpm for 30 minutes. The solid precipitate is removed and dried in an oven.

Example 28

Invention: Adduct of Sepiolite and the Adduct of HSAG with Hexyl Pyrrole (HSAG/EP)

(146) In this example the hexyl pyrrole used was synthetized by mixing hexanamine with 2,5-hexanedione, in equimolar ratio, at 130° C. for 3 hours. The hexanamine and 2,5-hexanedione used were acquired from Aldrich.

(147) The adduct of HSAG and hexyl pyrrole (HSAG/EP) was obtained with the same procedure described in example 25 for the adduct HSAG/SP, using hexyl pyrrole instead of serinol pyrrole.

(148) The adduct of sepiolite and HSAG/EP was obtained with the same procedure described in example 27 for the adduct of sepiolite and HSAG/SP, using HSAG/EP instead of HSAG/SP.

Example 29

Invention: Adduct of Sepiolite and the Adduct of HSAG with Dodecyl Pyrrole (HSAG/DDcP)

(149) In this example the dodecyl pyrrole used was synthetized by mixing dodecylamine with 2,5-hexanedione, in equimolar ratio, at 130° C. for 3 hours. The dodecylamine and 2,5-hexanedione used were acquired from Aldrich.

(150) The adduct of HSAG and dodecyl pyrrole (HSAG/DDcP) was obtained with the same procedure described in example 25 for the adduct HSAG/SP, using dodecyl pyrrole instead of serinol pyrrole.

(151) The adduct of sepiolite and HSAG/DDcP was obtained with the same procedure described in example 27 for the adduct of sepiolite and HSAG/SP, using HSAG/DDcP instead of HSAG/SP.

Example 30

Invention: Adduct of Sepiolite and CBN234/SP

(152) The adduct of sepiolite and CBN234/SP was obtained with the same procedure described in example 27 for the adduct of sepiolite and HSAG/SP, using CBN234/SP, obtained according to example 26, instead of HSAG/SP.

Example 31

Invention: Adduct of Sepiolite and HSAG/SP from Aqueous Dispersion

(153) In a 100 mL beaker were subsequently introduced: HSAG/SP (1 g), obtained according to example 25, and H.sub.2O (100 mL). The suspension was sonicated for 15 minutes with a probe-type sonicator. After this time, the HSAG/SP suspension in water was poured into a 250 mL beaker, which had been previously charged with 2 g of sepiolite and 100 mL of water. The thus obtained suspension, containing HSAG/SP and sepiolite in water, was left stirring for 12 hours at room temperature. After this time, the adduct of sepiolite and HSAG/SP is precipitated and it is removed by filtration on buchner.

(154) Tests of Extraction of Organic Substances from the Adducts in Table 1

(155) Tables 2A and 2B give the results of the tests of extraction of organic substances from the adducts, whose preparation has been described in examples 1-20.

(156) TABLE-US-00003 TABLE 2A Tests of extraction of the pyrrole com- pound from the adducts in Table 1..sup.a Adduct from Example No. 1 2 3 4 5 6 7 Pyrrole No No No No No No Yes compound in washing H.sub.2O .sup.aThe table gives the reply to the question: was an organic substance observed, by GC-MS analysis, in the extraction solution?

(157) TABLE-US-00004 TABLE 2B Tests of extraction of the pyrrole compound from the adducts in Table 1..sup.a Adduct from Example No. 8 9 10 11 13 14 15 16 17 18 19 20 Pyrrole /.sup.b /.sup.c Yes No No No No No No No No No compound in washing H.sub.2O .sup.aThe table gives the reply to the question: was an organic substance observed, by GC-MS analysis, in the extraction solution?; .sup.bwas the presence of 2,5-hexanedione detected in the wash water?; .sup.cwas the presence of serinol detected in the wash water?

(158) The extraction test and analysis of the solution obtained from extraction were carried out as given in the description of the experimental procedures, preparation of the adducts and characterization.

(159) To summarize, Table 2 gives the reply to the question: was at least one organic substance observed, by GC-MS analysis, in the extraction solution of the adduct?

(160) The adducts prepared in examples 1, 2 and 3 do not release any organic substance during the extraction test. In fact, “No” is reported in the first 3 columns of Table 2. “Yes” is reported in the columns of Table 2 relating to the tests for extraction of the adducts prepared in examples 7, 8, 9 and 10. This signifies that the adducts prepared in examples 7, 8, 9 and 10 release at least one organic substance.

(161) The adducts prepared in examples 4, 5, 6, 15, 16, 17, 18, 19, 20 were prepared with a carbon allotrope/silica ratio equal to 1:1. The tests for extraction of the adducts prepared in these tests did not lead to extraction of any organic substance.

(162) This result was obtained by preparing the adducts with various am ines (serinol, hexanam ine, (3-am inopropyl)triethoxysilane), various carbon allotropes (carbon black, high surface area graphite with nanometric dimensions), various inorganic oxides-hydroxides (silica, montmorillonite), and various methods of preparation (mixing the components of the adduct in a liquid or in the solid state). These results thus suggest that a sufficient amount of silica makes it possible to prevent extraction of organic substances from the adducts, provided they are formed from all the components envisaged by the present invention, even varying other conditions such as the type of amine, type of carbon allotrope, and type of inorganic oxide-hydroxide.

(163) Organic substances were detected in the extracts of the adducts prepared in examples 7, 8, 9 and 10, even though adducts 8 and 9 were prepared with a carbon black/silica ratio equal to 1:1. These results demonstrate that all components of the adducts must be present to avoid extractability of organic substances from said adducts.

(164) Tests of Stability of Dispersions in H.sub.2O of the Adducts in Table 1

(165) Tables 3A and 3B give the results of the tests of absorbance in the UV-Visible region, of the aqueous solutions of the adducts prepared in examples 1-20.

(166) TABLE-US-00005 TABLE 3A Tests of stability of dispersions in H.sub.2O of the adducts in Table 1. Absorbance measured at 300 nm Adduct from Example No. 1 2 3 4 5 6 7 Absorbance at t = 0 (A.sub.t=0) 4.11 4.11 4.11 4.11 2.93 4.11 0 Delta absorbance 0 0 0 0 0.36 0 = (A.sub.t = 0 − (A.sub.t=168h)

(167) TABLE-US-00006 TABLE 3B Tests of stability of dispersions in H.sub.2O of the adducts in Table 1. Absorbance measured at 300 nm Adduct from Example No. 8 9 10 11 12 13 14 15 16 17 18 19 20 Absorbance 0 0 0 0.89 1 4.05 4.0 4.11 2.89 4.11 2.91 4.11 2.90 at t = 0 (A.sub.t=0) Delta = = = 0.57 0.50 0 0 0 0.40 0 0.38 0 0.41 absorbance (A.sub.t=0 − (A.sub.t=168h)

(168) Preparation of the solutions and analysis of absorption were carried out as given in the description of the experimental procedures. In particular, Table 3 gives the values of absorbance measured at the end of preparation of the dispersions (time=0) and after 7 days (time=168 hours) in which the dispersions were held without stirring.

(169) The dispersions in water prepared with the adducts obtained from examples 1-4 showed the same high absorbance at time=0 and after 7 days. These results show that the adduct that contains serinol has a hydrophilic character, over a wide range of (carbon black)/(inorganic oxide-hydroxide) weight ratios, with silica or montmorillonite as the oxide-hydroxide. Entirely similar results were obtained with the adducts prepared in examples 15, 17 and 19, in which the amine is always serinol and various methods were employed for preparing the adducts, methods that are different from one another and are different from the method in example 1. Thus, changing the method for preparing the adduct does not alter the dispersibility in water of the adduct formed starting from serinol. Similar results were obtained with the adduct prepared in example 6, which has (3-aminopropyl)triethoxysilane as the amine.

(170) The dispersions in water prepared with the adducts obtained from example 5 showed a lower absorbance relative to that obtained with the adducts from examples 1-4 and showed an appreciable reduction in absorbance after seven days. This result may be attributed to the use of an amine with lipophilic character. The smaller absorbance and greater relative reduction of absorbance obtained with the adduct in example 5 may be attributed to the use of a larger amount of silica. Results entirely similar to those obtained with the adduct of example 5 were obtained with the adducts of examples 16, 18 and 20. As already commented for the absorbance of the adducts formed starting from serinol, changing the method of preparation of the adduct does not alter its dispersibility in water.

(171) The tests of absorbance of the adducts formed starting from the pyrrole compounds already formed gave results entirely similar to those obtained with the adducts formed starting from diketone and amine, for the same substituent of the nitrogen atom. This is found on comparing the absorbances obtained with the adduct from example 11 and with the adducts from examples 5, 16, 18 and 20. In these examples, a hexyl radical is the substituent of the nitrogen. The absorbance obtained with the adduct from example 12 is similar.

(172) The adducts formed in examples 7, 8, 9 and 10 do not cause any absorbance when dispersed in water. This indicates that these adducts do not remain in suspension. Each of these adducts lacks one component relative to the adduct according to the present invention.

(173) It should be noted that the adducts from examples 13 and 14 show absorbance, similar to that obtained with the adducts formed starting from serinol. This is certainly a noteworthy and interesting result, since trimethylpyrrole is a molecule that is certainly lipophilic, which should not impart a hydrophilic character to the adduct. This result may lead to the presumption of a mechanism for formation of the adduct that involves the formation of polar groups also starting from trimethylpyrrole.

(174) Tests of Stability of Dispersions in Toluene of the Adducts in Table 1

(175) Table 4 gives the results of the tests of absorbance in the UV-Visible region of the toluene solutions of the adducts prepared in examples 5, 11 and 16, i.e. of the adducts that contain the hexyl radical and that showed lower absorbance in water.

(176) TABLE-US-00007 TABLE 4 Tests of stability of dispersions in toluene of the adducts in Table 1. Absorbance measured at 300 nm Adduct from Example No. 5 11 16 Absorbance at t = 0 (A.sub.t=0) 4.11 4.11 4.11 Delta absorbance 0 0 0 (A.sub.t=0 − A.sub.t=168 h)

(177) It can be seen that the absorbance in toluene and the stability over time are greater than those in water and is similar for the three adducts, in line with the lipophilic character of the substituent of the nitrogen and thus of the amine and of the pyrrole compound.