METHOD FOR PREPARING A SILOXANE BASED POLYMERIC LIQUID MATERIAL AND MATERIALS MADE THEREFROM

Abstract

A polymeric liquid material formed of molecular building blocks of core-shell type architecture, wherein each building block consists of a hyperbranched polysiloxane core and a functional siloxane shell peripherally attached thereto, the material comprising bridging oxygen moieties (Si—O—Si), hydrolysable alkoxy moieties (Si—O—R) and organofunctional moieties (R′—Si—) and (R.sub.1-S1-R.sub.2) and less than 0.5 mass percent hydroxy moieties (Si—OH). The core has a degree of polymerization DP.sub.core in the range of 1.3 to 2.7, the shell is formed of R′-substituted siloxane moieties and has a degree of polymerization DP.sub.shell in the range of 0.3 to 2.5. At least 75 atomic percent of all Si atoms in the core are bonded exclusively to alkoxy or bridging oxygens, the remainder each being bonded to 3 oxygens and 1 carbon. The total Si to free hydrolysable alkoxy molar ratio in the material is 1:1.25 to 1:2.75, and the material has a viscosity in the range of 10-100,000 cP. A method for preparing the polymeric liquid material relies on first forming the hyper-branched polysiloxane core followed by a build-up of the functional siloxane shell. To do so, a reaction scheme based on adding stoichiometric amounts of acetic anhydride in a water-free environment is exploited.

Claims

1. A method for preparing a polymeric liquid material formed of molecular building blocks of core-shell type architecture, the method comprising: a) charging at least one silicon tetraalkoxide Si(OR).sub.4, wherein R is an unbranched or branched alkyl group with up to four carbon atoms; and, optionally, a functional admixture of one R″-organofunctional trialkoxysilane R″—Si(OR).sub.3 and, optionally, an R.sub.3,R.sub.4-organofunctional dialkoxysilane R.sub.3—Si(OR).sub.2—R.sub.4; or a mixture of different R″-organofunctional trialkoxysilanes and, optionally, at least one R.sub.3,R.sub.4-organofunctional dialkoxysilane;  in monomeric or in oligomeric form, into a reaction vessel together with a first stoichiometric amount of acetic anhydride selected according to the desired DP.sub.core, in the presence of a catalyst; b) heating up the reaction mixture provided in a) in a water-free, inert atmosphere under stirring to reach a desired reaction temperature and distilling off resulting acetic acid ester reaction product until the reaction and the flow of distillate stop, thereby forming said hyperbranched polysiloxane core; c) adding one R′-organofunctional trialkoxysilane R′—Si(OR).sub.3 and, optionally, an R.sub.1,R.sub.2-organofunctional dialkoxysilane R.sub.1—Si(OR).sub.2—R.sub.2, or a mixture of different R′-organofunctional trialkoxysilanes and, optionally, at least one R.sub.1,R.sub.2-organofunctional dialkoxysilane,  wherein:  R′ and R″ are independently selected substituents each representable as L-Z, wherein L is a linker group selected from the group consisting of —C.sub.6H.sub.4—, —C.sub.6H.sub.4—CH.sub.2—, —CH.sub.2—CH.sub.2—C.sub.6H.sub.4—CH.sub.2— and —[(CH).sub.2].sub.n— with n=0, 1, 2, 3, 4; and is a terminal functional group selected from the following: ##STR00015## wherein R* is selected from the group consisting of —H, —CH.sub.3, —C.sub.2H.sub.5, —C.sub.3H.sub.8, —C.sub.4H.sub.10 and —C.sub.6H.sub.5; or Z is —[(CH).sub.2].sub.m—CH.sub.3 with m=0, 1, 2, . . . , 11; and wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are substituents independently selected from the group consisting of —CH.sub.3, —C.sub.2H.sub.5, —C.sub.6H.sub.11, —CH═CH.sub.2, —CH.sub.2—CH.sub.2—Cl and —O.sub.5H.sub.5, with the provision that the triplets (R′, R.sub.1, R.sub.2) and (R″, R.sub.3, R.sub.4) are not identical;  together with a second stoichiometric amount of acetic anhydride selected according to the desired DP.sub.shell, optionally in the presence of a catalyst, to the hot reaction mixture formed in b) with continuing stirring, thus initiating a selective build-up of said functional siloxane shell onto the core produced in b), whereby further acetic acid ester is formed and distilled over, and continuing the reaction until the distillate flow ceases again; d) optionally building additional functional layers in the shell by repeating the addition and reaction protocol described in c) at least once; e) optionally removing low-molecular reaction products and/or residual starting materials in the reaction mixture by vacuum distillation through gradually lowering the pressure inside the reaction vessel and holding a final pressure in the range of 5 to 250 mbar for a period of time between 10 and 120 minutes, f) cooling down and isolating the polymeric liquid material thus obtained; wherein a) through e) are carried out in one and the same reaction vessel.

2. The method according to claim 1, wherein said functional admixture is zero.

3. The method according to claim 1, wherein R is methyl or ethyl.

4. The method according to claim 1, wherein the reaction temperature for b) through e) is in the range from 70° C. to 170° C., and the pressure during b) through d) is in the range of 0.1 bar to 2 bar.

5. The method according to claim 1, wherein the silicon tetraalkoxide Si(OR).sub.4 is tetraethoxysilane (TEOS) or tetramethoxysilane (TMOS) or a mixture of monomers and oligomers thereof.

6. The method according to claim 1, wherein an acetic acid ester reaction product is removed from the system through a distillation column comprising several theoretical plates in such a way that the lower boiling reaction product is separated from higher boiling residual reactants in solution whereby the latter are continuously fed back into the reaction mixture.

7. The method according to claim 1, wherein the catalyst is: Ti(OR″).sub.4 or Zn(II)alkanolates Zn(OR″).sub.2, wherein R″=—CH.sub.2CH.sub.3, —CH(CH.sub.3).sub.2, —CH.sub.2CH.sub.2CH.sub.3, —C(CH.sub.3).sub.3, —CH.sub.2CH.sub.2CH.sub.2CH.sub.3, or the catalyst is Ti(O—Si(CH.sub.3).sub.3).sub.4, wherein and the catalyst amount is between 0.01 and 1.5% on a mol basis of total alkoxysilane precursor used.

8. The method according to claim 1, wherein R′ is: i) R′=—C.sub.6H.sub.5, —CH═CH.sub.2, ii) R′=L-Z and L is —CH.sub.2— and Z=—[(CH).sub.2].sub.p—CH.sub.3 with p=0, 1, 2, 4, 6, 8, 10, 12, 14, iii) R′=L-Z and L=—CH.sub.2CH.sub.2CH.sub.2-(n-propyl) and Z=—Br, —Cl, —I, —SH, —OH, —NH.sub.2, —NH(BOC), —NH-(FMOC), -(2-oxiranyl), -methoxy-(2-oxiranyl), —N.sub.3, —SO.sub.3R, —PO.sub.3R.sub.2, -acrylate, -methacrylate, -ethacrylate, -propacrylate, -butacrylate, or iv) R′=L-Z and L=CH.sub.2, Z=vinyl, -acrylate, -methacrylate, -ethacrylate, -propacrylate, -butacrylate, and wherein R.sub.1 and R.sub.2 are equal and selected from the group consisting of —CH.sub.3, —C.sub.6H.sub.5, and —CH═CH.sub.2 or wherein R.sub.1=—CH.sub.3 and R.sub.2=—CH═CH.sub.2.

9. A polymeric liquid material, the material being formed of molecular building blocks of core-shell type architecture, each building block consisting of a hyperbranched polysiloxane core and a functional siloxane shell peripherally attached to said core, the material containing less than 0.5 mass percent hydroxy moieties (Si—OH), the core having a degree of polymerization DP.sub.core in the range of 1.3 to 2.7, the shell being formed of R′-substituted siloxane moieties and optionally R1-,R2-substituted siloxane moieties and having a degree of polymerization DP.sub.shell in the range of 0.3 to 2.5, wherein the total silicon to free hydrolysable alkoxy molar ratio in the material is 1:1.25 to 1:2.75, wherein the material has a viscosity in the range of 10 to 100′000 cP, and wherein the core is composed of non-organofunctional siloxane moieties comprising non-organofunctional terminally bonded siloxane moieties (Q.sup.1 speciation) of the general formula ##STR00016## and/or non-organofunctional disiloxane moieties (Q.sup.2 speciation) of the general formula ##STR00017## and/or non-organofunctional trisiloxane moieties (Q.sup.3 speciation) of the general formula ##STR00018## and/or non-organofunctional tetrasiloxane moieties (Q.sup.4 speciation) of the general formula ##STR00019## and wherein the shell is composed of: monoorganofunctional terminally bonded siloxane moieties (T.sup.1 speciation) of the general formula ##STR00020## and/or monoorganofunctional disiloxane moieties (T.sup.2 speciation) of the general formula ##STR00021## and/or monoorganofunctional trisiloxane (T.sup.3 speciation) moieties of the general formula ##STR00022## and, optionally, terminally bonded diorganofunctional siloxane (D′ speciation) moieties of the general formula ##STR00023## and/or diorganofunctional disiloxane (D.sup.2 speciation) moieties of the general formula ##STR00024## wherein R, R′, R.sub.1 and R.sub.2 are as defined in claim 1.

10. The polymeric liquid material according to claim 9, wherein the relative atomic ratio of T to Q species is in the range 0.03:1 to 1:1.

11. A hydrolysis product, wherein the product comprises a reaction product of the polymeric liquid material according to claim 9 and a predetermined amount of water or a predetermined amount of a water-solvent mixture.

12. A method comprising: providing the polymeric liquid material according to claim 9 in a coating or adhesive formulation or as a coupling agent to mediate incorporation of fillers into polymer matrices via the polymeric liquid material, or as a precursor for sol-gel chemical technology and preparing organofunctional gels and inorganic/organic nanocomposite materials as well as aerogels and xerogels derived thereof.

13. A method comprising: providing the hydrolysis product according to claim 11 in a coating or adhesive formulation or as a coupling agent to mediate the incorporation of fillers into polymer matrices via the polymeric liquid material, or as a precursor for sol-gel chemical technology, and preparing organofunctional gels and inorganic/organic nanocomposite materials as well as aerogels and xerogels derived thereof.

14. The method according to claim 4, wherein the reaction temperature for b) through e) is in the range of 100° C. to 150° C. and the pressure during b) through d) is in the range of 0.5 bar to 1.4 bar.

15. The method according to claim 14, wherein the reaction temperature for b) through e) is in the range from 120° C. to 140° C. and the pressure during b) through d) is in the range of 0.9 bar to 1.2 bar.

16. The polymeric liquid material according to claim 9, wherein the core has a degree of polymerization DP.sub.core in the range of 1.5 to 2.5, and the shell is formed of R′-substituted siloxane moieties and optionally R1-, R2-substituted siloxane moieties and has a degree of polymerization DP.sub.shell in the range of 1.0 to 2.3.

17. The polymeric liquid material according to claim 16, wherein the shell is formed of R′-substituted siloxane moieties and R1-, R2-substituted siloxane moieties.

18. The polymeric liquid material according to claim 10, wherein the relative atomic ratio of T to Q species is in the range 0.03:1 to 0.75:1.

19. The polymeric liquid material according to claim 17, wherein the relative atomic ratio of T to Q species is in the range 0.05:1 to 0.5:1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0148] The above mentioned and other features and objects of this invention and the manner of achieving them will become more apparent and this invention itself will be better understood by reference to the preceding description of various embodiments of this invention taken in conjunction with the accompanying drawings, wherein are shown:

[0149] FIG. 1 a rough classification of molecular and nano science in terms of number of constituent atoms and effective size;

[0150] FIG. 2 limitation of classical hydrolytic sol-gel methods to prepare functional nanoscale building blocks (NBBs); the product distribution of NBBs is determined by stochastic events in solution and relative reaction rates of the different alkoxide and silane precursors and hence poorly controllable;

[0151] FIG. 3 quantitative .sup.29Si NMR spectrum of the core, collected before the growth of the shell: DP.sub.core,initial=1.87;

[0152] FIG. 4 quantitative .sup.29Si NMR spectrum of a core-shell sample with a TEOS based core and MTES based shell: DP 2.40, DP.sub.core,final=2.40, ΔDP.sub.core=2.40-1.87=0.53, DP.sub.shell=1.86, n.sub.shell/n.sub.core=0.09, DP.sub.total=2.35;

[0153] FIG. 5 .sup.29Si-.sup.29Si INADEQUATE NMR spectrum and its projections of a core-shell sample with a TEOS based core and MTES based shell (n.sub.shell/n.sub.core=0.38, DP.sub.core,final=2.33, DP.sub.shell=2.08, DP.sub.total=2.26 from quantitative .sup.29Si NMR). Peaks are evidence of a covalent Si—O—Si bridge between the various T and Q species; on-diagonal peaks are evidence for a neighboring pair of the same species (e.g. Q.sup.2-Q.sup.2 or Q.sup.3-Q.sup.3). Neighboring species that are dissimilar show up as a pair of peaks symmetrical around the diagonal (e.g. the pair of T.sup.2-Q.sup.2 and Q.sup.2-T.sup.2 peaks);

[0154] FIG. 6 a) to d), model sketches for various molecular building blocks exhibiting terminal chemical functionality and classification in terms of the relative content of functional groups (n.sub.shell/n.sub.core) and other defining parameters; and

[0155] FIG. 7 a schematic illustration for the potential use of MBBs according to the present invention in applications: condensation and/or self-assembly leads to the formation of NBBs with homogeneous composition and custom tailorable surface chemistry.

DETAILED DESCRIPTION OF THE INVENTION

Example 1: Synthesis of TEOS/MTES Core-Shell MBB with n.SUB.core.:n.SUB.shell.=1:0.43

[0156] i) Fabrication of the hyPAS Core with Targeted DP.sub.Core=1.8/f=0.9 [0157] 52 g/250 mmol of tetraethoxysilane (TEOS) and 0.83 ml of tetrakis(trimethylsiloxy) titanium (0.75 mol % with respect to TEOS) were placed inside a 250 ml round bottom flask with distillation bridge. 23.2 g/225 mmol acetic anhydride Ac.sub.2O was added to the mixture and the glassware setup briefly purged with nitrogen, sealed, left under nitrogen pressure (balloon) and immersed into a hot oil bath at 140° C. The reaction mixture was brought to temperature with stirring at 500 rpm. After about 10 minutes from the time of immersion, the onset of the reaction was evidenced by an accelerating refluxing rate of the reaction byproduct ethyl acetate which started to make its way up the distillation tube. After approximately 15 minutes, a continuous stream of ethyl acetate was distilling over through the distillation bridge and collected in the capture vessel. The reaction continued for a total time of about 45 more minutes, at which point it stopped, commensurate with the ceasing of the ethyl acetate distilling over. The collection vessel was removed after a total reaction time of 1 h and emptied, yielding a total volume of 41 ml of collected reaction byproduct mixture.

[0158] ii) Growth of an MTES Shell Over a hyPAS Core with Targeted DP.sub.shell=3.6/g=1.8 [0159] In the shell growth step, the reaction mixture from the previous step a) was left stirring at the same reaction temperature (oil bath set to 140° C.) and a mixture consisting of 19.15 g/107 mmol MTES (methyltriethoxysilane) and 19.6 g/192 mmol acetic anhydride Ac.sub.2O was slowly added with a syringe pump over the course of about 100 minutes with continuing stirring. After approximately 10-15 minutes from the beginning of the dosing of the MTES/Ac.sub.2O mixture, the onset of ethyl acetate distilling over was again observed. After the addition was complete, the reaction mixture was kept stirring at temperature for another 20 minutes for a total reaction time of the shell growth step of approximately 2 hours. At the end of the reaction, with no more ethyl acetate boiling over, the heating source was removed from the reaction vessel and the mixture allowed cooling to room temperature. The crude product yield was 32.8 g of a viscous yellowish oil. The shell growth step also yielded 34 ml of distillate collected from the capture vessel.

Example 2: Synthesis of TEOS/VTES Core-Shell MBB with n.SUB.core.:n.SUB.shell.=1:0.15

[0160] i) Fabrication of the hyPAS Core with Targeted DP.sub.core,initial=2.4/f=1.2 [0161] The TEOS derived hyPAS core was prepared analogous to Example 1 i), with identical catalyst amount, temperature and stirring rate. The amount of TEOS and Ac.sub.2O used for the synthesis were 52 g/250 mmol and 30.6 g/300 mmol, respectively yielding a theoretical f factor of 1.2. The total reaction time was 1 h 30 minutes and produced 55 ml of distillate byproduct.

[0162] ii) Growth of a VTES Shell Over a hyPAS Core with g=1.12 [0163] The overgrowth of the TEOS hyPAS core was prepared analogous to Example 1 ii), with the main difference being the type and amount of functional trialkoxysilane used for shell growth. Accordingly, 7.13 g/37.5 mmol of vinyltriethoxysilane (VTES) and 4.32 g/42 mmol of Ac.sub.2O were dosed over the course of 30 minutes. The crude product yield was 32.8 g of a slightly viscous yellowish oil. The shell growth step also yielded 10 ml of distillate collected from the capture vessel.

Examples 3-9: Synthesis of Various Two-Component Core-Shell MMBs with Trialkoxysilane Shell Chemistry

[0164] i) Fabrication of the hyPAS Cores [0165] Pure tetraalkoxide hyPAS and mixed cores were prepared analogous to Example 1 i), with identical catalyst amount, temperature and stirring rate. The amounts of tetraalkoxide and optional functional trialkoysilane secondary precursor component as well as the selected amount of Ac.sub.2O used for the synthesis can be found in the above table for each experiment and are given in millimols [mmol]. The reaction time was 1 h 30 minutes.

[0166] ii) Growth of Organofunctional Trialkoxysilane Shells [0167] In the second step, shells based on various organofunctional trialkoxysilanes and mixtures thereof were grown according to the general process described in example 1 ii). The exact reaction parameters are given in the table below. Furthermore, the reaction products were characterized by means of .sup.29Si NMR spectroscopy and the material parameters (DP.sub.core, initial, DP.sub.core, final, DDP.sub.core, DP.sub.shell, DP.sub.total, n.sub.shell/n.sub.core) calculated using the equations given in the earlier discussion.

[0168] The set of examples presented here is to be viewed as experimental evidence for the broad applicability of the method and the wide range of materials chemistries accessible through it.

Examples 10-12: Synthesis of TEOS Core/(MTES/DMDES)-Shell MBBs with N.SUB.core.:n.SUB.shell.=1:(0.25-0.3)

[0169] The TEOS derived hyPAS core material was prepared analogous to Example 1 i), with identical catalyst amount, and stirring rate at an oil bath temperature of 140° C. The amount of TEOS and Ac.sub.2O used for the synthesis were 52 g/250 mmol and 25.5 g/250 mmol, respectively corresponding to a theoretical f factor of 1.0, (DP.sub.core, initial=2.0). The reaction time for the core formation was 1 h 30 minutes. The amount of condensate recovered from the core formation steps in each case was 45 ml, indicative of the good reproducibility of the core formation step.

[0170] Following the core formation, the temperature of the oil bath was reduced to 120° C. to partially restrain losses of the more volatile DMDES monomer and the system allowed to equilibrate for for 15 minutes. Shell growth was then triggered by the addition of the methyltriethoxysilane (MTES)/dimethyldiethoxysilane (DMDES) mixture over the course of 40 minutes by means of a laboratory syringe pump. The table below shows the selected shell composition parameters defined by the stoichiometry of added reagents (cells with bolded font) for examples 11 through 13. The theoretical g-factor used this series is around 1.1.

TABLE-US-00001 n.sub.MTES n.sub.MTES n.sub.Ac2O g t.sub.reaction V.sub.condensate n.sub.shell:n.sub.core [mmol] [mmol] [mmol] [ ] [min] [ml] Example 0.29 47.7 25.1 84.6 1.16 100 16 10 Example 0.30 37.8 37.3 79.3 1.05 115 13 11 Example 0.27 25.2 43.3 74.0 1.09 85 10 12

[0171] The as obtained materials were transparent, slightly yellow oily liquids. The reaction mixtures were then further purified by distilling off unreacted monomers and acetic anhydride by evacuating the reaction vessel to 50 mbar, heating the mixture to 150° C. with continued stirring and holding at temperature/vacuum for a period of 40 minutes.

Examples 13-18: Gelation Tests of (TEOS/MTES) and (TEOS/VTES) Core-Shell NBB Derived NBB Hydrolysis Products

[0172] A standard hydrolysis recipe was used to transform TEOS/MTES and TEOS/VTES core shell prepared with under identical conditions as given in example 1 but with varying n.sub.shell:n.sub.core ratios and adjusted f factors, respectively to their corresponding NBB hydrolysis products. The following preparation scheme was used for the preparation of the NBB sol (hydrolysis products):

[0173] 4.32 g (6.4 ml) of ethanol and 3.84 of NBB crude mixture with TEOS core/MTES shell were weighed in and heated to 40° C. in an Erlenmeyer beaker with stirring. After a waiting period of 5 minutes, 15 microliters of 10% H.sub.2SO.sub.4, 0.27 ml of distilled water were added to the mixture. After a brief homogenization period, the beaker was sealed off with parafilm, removed from the heating source and left standing under ambient condition for 60 hours.

[0174] The so-obtained NBB sols were then gelled using the following standard protocol: 7 ml of NBB sol were diluted with 16.3 ml of absolute ethanol denatured with 2% methyl ethyl ketone and 0.78 ml of distilled water in a 100 ml beaker. Next, 0.28 ml of 5.5M ammonia solution were added to the dilute sol and the mixture stirred for 5 minutes. The activated sol was then transferred to a 50×50×20 mm square plastic mold and allowed to gel at room temperature and the gelation time recorded.

TABLE-US-00002 Chemistry t.sub.gel [core/shell] n.sub.shell:n.sub.core f [ ] g [ ] [min] Example 13 TEOS/MTES 0.15 1.2 1.27 26 Example 14 TEOS/MTES 0.30 1.0 1.27 34 Example 15 TEOS/MTES 0.60 0.9 1.27 33 Example 16 TEOS/VTES 0.15 1.2 1.12 30 Example 17 TEOS/VTES 0.30 1.0 1.12 76 Example 18 TEOS/VTES 0.60 0.9 1.12 220

[0175] From the above examples it can be seen that the gelation times are rather fast, especially by comparison with the reference examples given below. Furthermore, it is rather independent of the n.sub.shell/n.sub.core ratio for MTES but increases rapidly with increasing n.sub.shell/n.sub.core for the VTES functional materials.

Comparative Examples 19-24: Gelation Tests of (TEOS/MTES) and (TEOS/VIES) Sols Obtained by Classical Hydrolysis of Alkoxide Mixtures

[0176] Classical hydrolysis was used to prepare standard sols from identical compound mixtures of TEOS/MTES and TEOS/VTES and their gelation times measured for comparison to the MBB->NBB approach according to this invention. The molar ratio TEO to (MTES/VTES) was varies over a range similar to above examples within a range of functional silane to TEOS molar ratio window ranging from 0.15 to 0.47.

[0177] Sols were prepared in an identical fashion as the above described hydrolyzed NBB sols: 4.32 g (6.4 ml) of ethanol and 3.84 of TEOS/MTES or TEOS VTES mixture, respectively, shell were weighed in and heated to 40° C. in an Erlenmeyer beaker with stirring. After a waiting period of 5 minutes, 15 microliters of 10% H.sub.2SO.sub.4, 0.27 ml of distilled water were added to the mixture. After a brief homogenization period, the beaker was sealed off with parafilm, removed from the heating source and left standing under ambient condition for 60 hours.

[0178] Again, a gelation protocol identical to the one in the above examples 18-23 was used to carry out the gelation tests. A summary of the comparative experiments is shown in the table below.

TABLE-US-00003 Sol chemistry (MTES/VTES) n.sub.TEOS n.sub.MTES n.sub.VTES t.sub.reaction [cohydrolysis] to TEOS ratio [mmol] [mmol] [mmol] [min] Example TEOS/MTES 0.47 16.8 8.0 — >300 19 min Example TEOS/MTES 0.26 15.4 4.0 — >300 20 min Example TEOS/MTES 0.15 13.3 2.0 — >300 21 min Example TEOS/VTES.sup.  0.43 16.3 — 7.1 >300 22 min Example TEOS/VTES.sup.  0.25 14.4 — 3.6 >300 23 min Example TEOS/VTES.sup.  0.15 11.9 — 1.8 >300 24 min

[0179] All samples took more than 5 hours to gel and were left standing over night. Surprisingly, the next morning all samples had gelled. In conclusion, by comparison it becomes apparent that the sols obtained by classical hydrolysis gel much more slowly than their MBB->NBB sol derived analogues. This is attributed to the higher degree of control over the molecular scale building blocks of the sols obtained using the methodology described in this invention.

Overview Table with Examples

[0180]

TABLE-US-00004 Example Number 1 2 3 4 5 6 System definition TEOS/ TEOS/ D-40 (1) D-40 (2) TMOS/ TEOS/ MTES VTES VTMS DEPETES Internal reference 48 38 85 86 95 62 n /n 0.43 0.15 0.14 0.12 0.26 0.60 f 0.91 1.20 0.36 0.36 0.80 0.91 g 1.77 1.13 2.65 1.48 1.11 1.06 DC 3.55 2.26 5.30 2.95 2.21 2.12 Reaction temperature (oil bath setting) 140° C. 140° C. 140° C. 140° C. 140° C. 140° C. Catalyst Ti(OTMS) Ti(OTMS) Ti(OTMS) Ti(OTMS) Ti(OTMS) Ti(OTMS) Catalyst concentration [% mol based 0.7 0.7 0.7 0.7 0.7 0.7 on n ] Stoichiometry used in experiments [mols] [mols] [mols] [mols] [mols] [mols] i) Core fabrication TEOS (tetraethylorthosilicate) 0.250 0.250 0.250 TEOS-40 (tetraethyl  oligomers) 0.173 0.173 TMOS (tetramethylorthosilicate) 0.250 TTB (Titaniumtetrabutoxide) DEPETES ((Diethylphosphatoeth- yl)triethoxysilane) Acetic anhydride (AA ) 0.227 0.300 0.062 0.062 0.200 0.227 ii) shell growth MTES (Methyltriethoxysilane) 0.107 0.024 DMDES (Dimethyldiethoxysilane) VTES (Vinyltriethoxysilane) 0.038 0.021 VTMS (Vinyltrimethoxysilane) 0.064 DEPETES ((Diethylphosp 0.150 3-TESPM (3-(Triethoxysilyl)propyl- methacrylate) BOC-APTES (BOC  aminopro- pyltriethoxysilane) Acetic anhydride (AA#z,899) 0.190 0.042 0.062 0.031 0.071 0.159 Example Number 7 8 9 13 System definition TEOS/ (TEOS/3 TEOS + TEOS/ DEPETES TESPM DEPETES)/ (MTES + MTES DMDES) Internal reference 63 80 87 89 n /n 0.15 0.24 0.31 0.25 f 1.20 1.00 0.86 1.00 g 1.14 1.74 1.78 1.25 DC 2.27 3.48 3.55 2.50 Reaction temperature (oil bath setting) 140° C. 140° C. 140° C. 140° C. Catalyst Ti(OTMS) Ti(OTMS) Ti(OTMS) Ti(OTMS) Catalyst concntration [% mol based 0.7 0.7 0.7 0.7 on n ] Stoichiometry used in experiments [mols] [mols] [mols] [mols] i) Core fabrication TEOS (tetraethylorthosilicate) 0.250 0.250 0.107 0.250 TEOS-40 (tetraethyl  oligomers) TMOS (tetramethylorthosilicate) TTB (Titaniumtetrabutoxide) DEPETES ((Diethylphosphatoeth- 0.024 yl)triethoxysilane) Acetic anhydride (AA ) 0.300 0.250 0.113 0.250 ii) shell growth MTES (Methyltriethoxysilane) 0.040 0.027 DMDES (Dimethyldiethoxysilane) 0.036 VTES (Vinyltriethoxysilane) VTMS (Vinyltrimethoxysilane) DEPETES ((Diethylphosp 0.0 3-TESPM (3-(Triethoxysilyl)propyl- 0.061 methacrylate) BOC-APTES (BOC  aminopro- pyltriethoxysilane) Acetic anhydride (AA#z,899) 0.042 0.106 0.071 0.079 indicates data missing or illegible when filed

TABLE-US-00005 Summary of results 1 2 3 4 5 6 7 8 9 13 n /n  (NMR) 0.38 0.14 0.10 0.10 0.23 0.62 0.14 0.26 n.d. 0.22 DP  from stoichiometry 2.34 2.38 n.d. n.d. 2.17 1.93 2.38 2.29 2.16 2.10 DP  (from NMR) 2.26 2.22 2.46 2.42 1.86 1.31 2.07 1.98 n.d. 1.95 DP  (from NMR) 2.33 2.30 2.48 1.94 1.87 2.21 2.08 n.d. 2.10 DP  (from stoichiometry) 1.82 2.40 0.72 0.72 1.80 1.82 2.40 2.00 1.7 2.00 DP  (from NMR) n.d. n.d. n.d. n.d. 1.73 n.d. n.d. n.d. n.d. n.d. Delta DP  (from NMR) n.d. n.d. n.d. n.d. 0.22 n.d. n.d. n.d. n.d. n.d. DC  = 2  (from stoichiometry) 3.55 2.26 5.30 2.95 2.21 2.12 2.27 3.48 3.55 2.50 (n /n    DeltaDP ) + DP  (from NMR) n.d. n.d. n.d. n.d. 2.37 n.d. n.d. n.d. n.d. n.d. DP  (from NMR) 2.08 1. 2.006 1.86 1.52 0.40 1.06 1.58 n.d. 1.29 Q  speciation, initial (core), normalized Q n.d. n.d. n.d. n.d. 3.0 n.d. n.d. n.d. n.d. n.d. Q n.d. n.d. n.d. n.d. 1. n.d. n.d. n.d. n.d. n.d. Q n.d. n.d. n.d. n.d. 41.9 n.d. n.d. n.d. n.d. n.d. Q n.d. n.d. n.d. n.d. 37.2 n.d. n.d. n.d. n.d. n.d. Q n.d. n.d. n.d. n.d. 4.7 n.d. n.d. n.d. n.d. n.d. DP n.d. n.d. n.d. n.d. 1.7 n.d. n.d. n.d. n.d. n.d. Q  speciation, final, after shell growth, normalized Q 7.9 6.0 11.4 10.6 3.6 4.5 5.4 n.d. 5.3 Q 36.1 36.9 41.9 40.4 21.4 19.7 27.5 n.d. 26.7 Q 39.8 40.3 36.8 44.7 43.7 44.1 41.5 n.d. 43.2 Q 14.1 10.2 10.7 26.4 18.5 21. n.d. 22.6 Q 2.6 2.6 1.2 1.5 4.0 3.5 0.9 4.4 n.d. 2.2 DP 2.3 2.3 2.5 2. 1.9 1.9 2.2 2.1 n.d. 2.1 Delta DP n.d. n.d. n.d. n.d. 0. n.d. n.d. n.d. n.d. n.d. Consumption of AA  for Delta DP  (mols) n.d. n.d. n.d. n.d. 0.03 n.d. n.d. n.d. n.d. n.d. AA  left for  condensation (mols) n.d. n.d. n.d. n.d. 0.04 n.d. n.d. n.d. n.d. n.d. T  speciation, after shell growth, normalized T 32.5 10.2 29.3 17.3 9.1 0.0 1.2 11.8 n.d. 14.2 T 45.9 48.9 49.0 52.3 41.7 6.6 28.1 43.5 n.d. 37.2 T 18.8 34.4 19.9 29.8 41.6 26.9 46.0 35.9 n.d. 28.9 T 2.8 6.5 1.8 0.6 7.6 66.5 24.7 8.8 n.d. 19.7 DP  from leftover AA n.d. n.d. n.d. n.d. 1.37 n.d. n.d. n.d. n.d. n.d. DP  from NMR (T + D) 2.08 1.63 2.06 1.86 1.52 0.40 1.06 1.58 n.d. 1.29 Q  and T  species final, normalized to total Q 5.7 5.3 10.4 9.7 2.9 1.5 4.0 4.3 n.d. 4.3 Q 26.2 32.5 38.1 36.6 17.4 12.2 28.2 21.8 n.d. 21.8 Q 28.8 35.5 32.1 33.4 36.3 27.0 38.9 33.0 n.d. 35.3 Q 9.8 12.4 9.2 9.7 21.4 18.9 18.3 16.8 n.d. 18.5 Q 1.9 2.3 1.0 1.4 2.2 0.8 n.d. 1.2 T 9.0 1.2 2.7 1.6 1.7 0.0 0.1 2.4 n.d. 1.2 T 12.6 5.9 4.5 4.8 7.8 2.5 9.0 n.d T 5.2 4.1 1.8 2.8 7.8 10.4 5.5 7.4 n.d 2.4 T 0.8 0.8 0.2 0.1 1.4 25.6 2.9 1.8 n.d 1.6 D 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 n.d. 4.2 D 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 n.d. 3.0 D 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 n.d. 2.7 indicates data missing or illegible when filed