HYDROCARBON-BASED POLYMERS BEARING TWO ALKOXYSILANE END GROUPS

Abstract

Hydrocarbon-based polymer of formula (1) bearing alkoxysilane end groups:

##STR00001## in which: is a double or single bond; each of R.sub.2, R.sub.3, R.sub.4 and R.sub.5 is H, a halo, an alkoxycarbonyl or an alkyl, m and p are each from 0 to 5, each of R and R is an alkyl, Z is an alkylene, optionally interrupted with COO, q is 0 or 1, r is 0, 1 or 2, and n is an integer such that the number-average molar mass Mn of the polymer is from 400 to 50 000 g/mol, and its polydispersity index (PDI) is from 1.0 to 2.0.

Preparation by ring-opening metathesis polymerization for 2 hours to 24 hours.

Adhesive composition comprising polymer (1) and crosslinking catalyst. Bonding by assembly of two substrates using this adhesive composition.

Claims

1. A hydrocarbon-based polymer comprising two alkoxysilane end groups, said hydrocarbon-based polymer being of formula (1): ##STR00018## in which: each carbon-carbon bond of the chain noted as is a double bond or a single bond, in accordance with the valency rules of organic chemistry; the groups R.sub.2, R.sub.3, R.sub.4 and R.sub.5 are each, independently of the other groups or otherwise, a hydrogen, a halo group, an alkoxycarbonyl group or an alkyl group, the groups R.sub.2 to R.sub.5 possibly being linked together as members of the same saturated or unsaturated ring or heterocycle, m and p are integers each within a range from 0 to 5, the sum m+p itself being within a range from 0 to 10, R and R, which may be identical or different, each represent a linear or branched, preferably linear, alkyl group comprising from 1 to 4, Z is a divalent group chosen from alkylene groups, optionally interrupted with an ester function, and comprising from 1 to 22 and preferably from 1 to 6 carbon atoms, q is an integer equal to 0 or 1, r is an integer equal to 0, 1 or 2, and n is an integer such that the number-average molar mass Mn of the hydrocarbon-based polymer of formula (1) is within a range from 400 to 50 000 g/mol, and the polydispersity index (PDI) of the hydrocarbon-based polymer of formula (1) is within a range from 1.0 to 2.0.

2. The hydrocarbon-based polymer comprising two alkoxysilane end groups as claimed in claim 1, said polymer being such that the group of formula [Z].sub.qSi(R).sub.r(OR).sub.3-r is chosen from Si(OCH.sub.3).sub.3; SiCH.sub.3(OCH.sub.3).sub.2; CH.sub.2Si(OCH.sub.3).sub.3; CH.sub.2SiCH.sub.3(OCH.sub.3).sub.2; COO(CH.sub.2).sub.3Si(OCH.sub.3).sub.3); and COO(CH.sub.2).sub.3SiCH.sub.3(OCH.sub.3).sub.2).

3. The hydrocarbon-based polymer comprising two alkoxysilane end groups as claimed in claim 1, said polymer being of formula (1): ##STR00019##

4. The hydrocarbon-based polymer comprising two alkoxysilane end groups as claimed in claim 1, said hydrocarbon-based polymer being of formula (2) or of formula (3): ##STR00020## in which the bond means that the bond is geometrically oriented on one side or the other relative to the double bond (cis or trans).

5. The hydrocarbon-based polymer comprising two alkoxysilane end groups as claimed in claim 1, said hydrocarbon-based polymer being of formula (4): ##STR00021##

6. The hydrocarbon-based polymer comprising two alkoxysilane end groups as claimed in claim 5, said polymer being of formula (4): ##STR00022##

7. The hydrocarbon-based polymer comprising two alkoxysilane end groups as claimed in claim 5, said hydrocarbon-based polymer being of formula (5) or of formula (6): ##STR00023## in which the bond means that the bond is geometrically oriented on one side or the other relative to the double bond (cis or trans).

8. A process for preparing at least one hydrocarbon-based polymer as claimed in claim 1, said process comprising at least one step of ring-opening metathesis polymerization in the presence of: at least one metathesis catalyst, at least one chain-transfer agent (CTA) chosen from the group formed by alkenylsilanes bearing a carbon-carbon double bond, preferably from the group formed by vinyltrimethoxysilane, allyltrimethoxysilane and 3-(trimethoxysilyl)propyl acrylate, and at least one compound chosen from compounds comprising at least one hydrocarbon-based ring and from 6 to 16 carbon atoms per ring, said ring comprising at least one carbon-carbon double bond, and substituted derivatives of this compound, said compound being of formula (7): ##STR00024## in which: each carbon-carbon bond of the chain noted as is a double bond or a single bond, in accordance with the valency rules of organic chemistry; the groups R.sub.2, R.sub.3, R.sub.4 and R.sub.5 are each, independently of the other groups or otherwise, a hydrogen, a halo group, an alkoxycarbonyl group or an alkyl group, the groups R.sub.2 to R.sub.5 possibly being linked together as members of the same saturated or unsaturated ring or heterocycle, m and p are integers each within a range from 0 to 5, the sum m+p itself being within a range from 0 to 10, said step being performed for a time of between 2 hours and 24 hours, (limits inclusive).

9. The preparation process as claimed in claim 8, such that the chain-transfer agent has the formula CH.sub.2CH[Z].sub.qSi(R).sub.r(OR).sub.3-r in which: R and R, which may be identical or different, each represent a linear or branched alkyl group comprising from 1 to 4 carbon atoms, Z is a divalent group chosen from alkylene groups, optionally interrupted with an ester function, and comprising from 1 to 22 carbon atoms, q is an integer equal to 0 or 1, and r is an integer equal to 0, 1 or 2.

10. The preparation process as claimed in claim 8, such that the chain-transfer agent is chosen from: CH.sub.2CHSi(OCH.sub.3).sub.3; CH.sub.2CHSiCH.sub.3(OCH.sub.3).sub.2; CH.sub.2CHCH.sub.2Si(OCH.sub.3).sub.3; CH.sub.2CHCH.sub.2SiCH.sub.3(OCH.sub.3).sub.2; CH.sub.2CHCOO(CH.sub.2).sub.3Si(OCH.sub.3).sub.3; and CH.sub.2CHCOO(CH.sub.2).sub.3SiCH.sub.3(OCH.sub.3).sub.2.

11. The preparation process as claimed in claim 8, said process being such that the mole ratio of the CTA to the compound comprising at least one hydrocarbon-based ring is within a range from 1 to 10 mol %.

12. The preparation process as claimed in claim 8, said process also comprising at least one additional hydrogenation of double bonds.

13. The preparation process as claimed in claim 12, such that the additional hydrogenation is performed by catalytic hydrogenation, under hydrogen pressure and in the presence of a hydrogenation catalyst.

14. An adhesive composition comprising at least one polymer as claimed in claim 1 and from 0.01% to 3% by weight of at least one crosslinking catalyst.

15. A process for bonding by assembly of two substrates, comprising: the coating of an adhesive composition as claimed in claim 14, in liquid form, preferably in the form of a layer with a thickness in a range from 0.3 to 5 mm, onto at least one of the two surfaces that belong, respectively, to the two substrates to be assembled, and which are intended to be placed in contact with each other on a tangency surface; and then the effective placing in contact of the two substrates on their tangency surface.

Description

EXAMPLES

[0115] The examples that follow illustrate the invention without, however, limiting its scope.

[0116] The synthetic reactions of the examples were performed in one or two steps, with an optional step of synthesis of the transfer agent and a step of ring-opening polymerization of cyclooctene in the presence of a Grubbs catalyst and a transfer agent. The transfer agent was a commercial product or a product synthesized specially for this use.

[0117] The general scheme of the polymerization reactions of the examples is given below, and will be explained on a case by case basis in the examples.

##STR00014##

[0118] Herein, CTA is the chain-transfer agent, COE is cyclooctene, 2G Grubbs is the catalyst of formula (9) and Y (equal to [Z].sub.qSi(R).sub.r(OR).sub.3-r) is chosen from the group formed by Si(OCH.sub.3).sub.3 (in the case where the CTA is vinyltrimethoxysilane), CH.sub.2Si(OCH.sub.3).sub.3 (in the case where the CTA is allyltrimethoxysilane) and COO(CH.sub.2).sub.3Si(OCH.sub.3).sub.3 (in the case where the CTA is 3-(trimethoxysilyl)propyl acrylate); x is the number of moles of CTA; n is the number of moles of COE, and s is the repetition number of the monomer unit in the polymer.

[0119] In any event, s is a number less than or equal to n, preferably equal to n.

[0120] The reaction could last from 2 hours to 24 hours.

[0121] Experimental Protocol

[0122] All the experiments were performed, if necessary, under an argon atmosphere.

[0123] All the reagents (cyclooctene (COE), the second-generation Grubbs (or 2G Grubbs) catalyst of formula (9), vinyltrimethoxysilane, allyltrimethoxysilane and 3-(trimethoxysilyl)propyl acrylate) were products from the company Sigma-Aldrich.

[0124] Cyclooctene (COE) was degassed a first time, then dried over CaH.sub.2 and finally distilled before use.

[0125] All the other products were used as received.

[0126] The DSC (differential scanning calorimetry) analyses were performed using aluminum capsules, on a Setaram DSC 131 machine calibrated with indium, at a rate of 10 C./min and under a continuous stream of helium (at 25 mL/min).

[0127] The NMR spectra were recorded on Bruker AM-500 and Bruker AM-400 spectrometers, at 298 K in CDCl.sub.3. The chemical shifts were referenced relative to tetramethylsilane (TMS) using the proton (.sup.1H) or carbon (.sup.13C) resonance of the deuterated solvent. The chemical shift of .sup.29Si was referenced relative to TMS.

[0128] The number-average and weight-average molar masses (M.sub.n and M.sub.w) and the polydispersity index PDI (M.sub.w/M.sub.n) of the polymers were determined by size exclusion chromatography (SEC), with polystyrene calibration, using a Polymer Laboratories PL-GPC 50 instrument. The samples were eluted with tetrahydrofuran (THF) (product from the company Sigma-Aldrich) at 30 C. and at 1.0 mL/min. The mass spectra were recorded with an AutoFlex LT high-resolution spectrometer (Bruker) equipped with an N.sub.2 pulsed laser source (337 nm, 4 ns pulse width).

[0129] General Polymerization Procedure

[0130] All the polymerizations were performed in a similar manner. The only differences concerned the nature and the initial concentration of the chain-transfer agent (CTA).

[0131] A typical procedure here is described below. It corresponds to test No. 2 of Table 1 (Example 1).

[0132] The monomer COE (1.4 mL, 10.8 mmol) and dry CH.sub.2Cl.sub.2 (5 mL) were placed in a 100 mL round-bottomed flask into which was also placed a Teflon-coated magnetic stirring bar. The flask and its contents were then placed under argon. CTA, in this case vinyltrimethoxysilane (82.7 L, 0.54 mmol), was then introduced into the flask by syringe. The flask was immersed in an oil bath at 40 C. immediately after the addition, via a cannula, of the G2 catalyst (5.0 mg, 5 mol) dissolved in CH.sub.2Cl.sub.2 (2 mL). The reaction mixture became very viscous within two minutes. The viscosity then decreased slowly over the following 10 minutes. After 24 hours, counting from the addition of the catalyst, the product present in the flask was extracted after concentrating the solvent under vacuum. A product was then recovered after precipitation from methanol (which made it possible to recover the catalyst in the filtrate), filtration and drying under vacuum (94% yield in this case). The analysis made it possible to demonstrate that the product was indeed the polymer having the expected formula.

[0133] All the polymers prepared in the examples were recovered as colorless solid powders, readily soluble in chloroform and insoluble in methanol.

Example 1: Synthesis of a Polymer Comprising Two Alkoxysilane End Groups Starting with Cyclooctene (COE) and Vinyltrimethoxysilane

[0134] The reaction was performed according to scheme 2 below:

##STR00015##

[0135] The expected polymer was thus synthesized. It had a melting point of 57 C.

[0136] Various tests were performed according to this reaction. They are collated in Table 1 below.

TABLE-US-00001 TABLE 1 Test [COE].sub.0/[CTA].sub.0/[Ru].sub.0 Conversion Mn.sub.SEC.sup.(b) No..sup.(a) (mol/mol) (%) (g/mol) PDI 1 2000:200:1 100 5500 1.59 2 2000:100:1 100 7000 1.65 3 2000:50:1 100 14 400 1.83 4 2000:20:1 100 51 700 1.85 in which CTA = vinyltrimethoxysilane and [X].sub.0 = initial concentration of X .sup.(a)the polymerization was performed under the following particular conditions: 5 mol of catalyst (G2), 7 mL of CH.sub.2Cl.sub.2, temperature of 40 C., time 24 hours .sup.(b)the Mn.sub.SEC values were determined by SEC in THF at 30 C.

[0137] NMR analyses of the polymer obtained in test No. 2 gave the following values, which confirmed the structural formula of the polymer:

[0138] .sup.1H NMR (CDCl.sub.3, 400 MHz, 298 K) .sub.ppm: 5.39; 1.97, 1.30; end groups: 6.43-6.47 (m, 2H, CHCHSi), 5.39 (m, 2H, CHCHSi), 3.57 (s, 18H, (CH.sub.3O).sub.3Si).

[0139] .sup.13C NMR (.sup.1H) (CDCl.sub.3, 100 MHz, 298 K) .sub.ppm: 130.2 (trans) 129.6 (cis), 36.6, 32.6, 29.1, 27.2); end groups: 154.9 (CHCHSi), 117.1 (CHCHSi), 50.7 ((CH.sub.3O).sub.3Si).

Example 2: Synthesis of a Polymer Comprising Two Alkoxysilane End Groups Starting with Cyclooctene (COE) and Allyltrimethoxysilane

[0140] The reaction was performed according to scheme 3 below:

##STR00016##

[0141] The expected polymer was thus synthesized. It had a melting point of 54 C.

[0142] Various tests were performed according to this reaction. They are collated in Table 2 below.

TABLE-US-00002 TABLE 2 Test [COE].sub.0/[CTA].sub.0/[Ru].sub.0 Conversion Mn.sub.SEC.sup.(b) No..sup.(a) (mol/mol) (%) (g/mol) PDI 5 2000:200:1 100 5500 1.59 6 2000:100:1 100 7000 1.65 7 2000:50:1 100 14 400 1.83 8 2000:20:1 100 51 700 1.85 in which CTA = allyltrimethoxysilane and [X].sub.0 = initial concentration of X .sup.(a)the polymerization was performed under the following particular conditions: 5 mol of catalyst (G2), 7 mL of CH.sub.2Cl.sub.2, temperature of 40 C., time 5 hours .sup.(b)the Mn.sub.SEC values were determined by SEC in THF at 30 C.

[0143] NMR analyses of the polymer obtained in test No. 6 gave the following values, which confirmed the structural formula of the polymer:

[0144] .sup.1H NMR (CDCl.sub.3, 400 MHz, 298 K) .sub.ppm: 5.38; 5.35, 2.02, 1.97, 1.33; end groups: 5.38-5.35 (m, 4H, CHCHSi), 3.57 (s, 18H, (CH.sub.3O).sub.3Si), 1.64-1.55 (m, 4H, CH.sub.2Si).

[0145] .sup.13C NMR (.sup.1H) (CDCl.sub.3, 100 MHz, 298 K) .sub.ppm: 130.3 (trans) 129.8 (cis), 32.6, 29.7, 29.1, 27.2; end groups: 129.9-130.3 (CHCHCH.sub.2Si), 122.6 (CHCHCH.sub.2Si), 50.7 ((CH.sub.3O).sub.3Si), 15.1 (CH.sub.2Si).

[0146] DSC analysis of the polymer obtained in test No. 6 (performed in first sequence, from 60 C. to 80 C., at 10 C./min) gave the following values for the polymer: crystallization temperature T.sub.c=45.0 C. and melting point T.sub.m=54.6 C.

Example 3: Synthesis of a Polymer Comprising Two Alkoxysilane End Groups Starting with Cyclooctene (COE) and 3-(Trimethoxysilyl)Propyl Acrylate

[0147] The reaction was performed according to scheme 4 below:

##STR00017##

[0148] The expected polymer was thus synthesized. It had a melting point of 59 C.

[0149] Various tests were performed according to this reaction. They are collated in Table 3 below.

TABLE-US-00003 TABLE 3 Test [COE].sub.0/[CTA].sub.0/[Ru].sub.0 Conversion Mn.sub.SEC.sup.(b) No..sup.(a) (mol/mol) (%) (g/mol) PDI 9 2000:200:1 100 3700 1.43 10 2000:100:1 100 7100 1.70 11 2000:50:1 100 11 600 1.80 12 2000:20:1 100 34 100 1.68 in which CTA = 3-(trimethoxysilyl)propyl acrylate and [X].sub.0 = initial concentration of X .sup.(a)the polymerization was performed under the following particular conditions: 5 mol of catalyst (G2), 7 mL of CH.sub.2Cl.sub.2, temperature of 40 C., time 5 hours .sup.(b)the Mn.sub.SEC values were determined by SEC in THF at 30 C.

[0150] NMR analyses of the polymer obtained in test No. 10 gave the following values, which confirmed the structural formula of the polymer:

[0151] .sup.1H NMR (CDCl.sub.3, 400 MHz, 298 K) .sub.ppm: 5.38; 5.35, 2.01, 1.97, 1.31; end groups: 5.38-5.35 (m, 2H, CHCHSi), 3.57 (s, 18H, (CH.sub.3O).sub.3Si), 1.64-1.55 (m, 4H, CH.sub.2Si).

[0152] .sup.13C NMR (.sup.1H) (CDCl.sub.3, 100 MHz, 298 K) .sub.ppm: 130.3 (trans) 129.8 (cis), 32.6, 29.7, 29.1, 27.2; end groups: 129.9-130.3 (CHCHCH.sub.2Si), 122.6 (CHCHCH.sub.2Si), 50.7 ((CH.sub.3O).sub.3Si), 15.1 (CH.sub.2Si).

[0153] .sup.29Si NMR (59 MHz, CDCl.sub.3, 298 K) .sub.ppm: 42.4 (Si(OCH.sub.3).sub.3.

[0154] DSC analysis of the polymer obtained in test No. 6 (performed in first sequence, from 60 C. to 80 C., at 10 C./min) gave the following values for the polymer: crystallization temperature T.sub.c=45.0 C. and melting point T.sub.m=54.6 C.

Example 4: Synthesis of an Adhesive Composition from a Polymer Comprising Two Alkoxysilane End Groups of Example 1

[0155] An adhesive composition was prepared comprising 0.2% by weight of a crosslinking catalyst formed from dioctyltin dineodecanoate (product Tib kat 223 from the company Tib Chemicals) and the polymer according to the invention obtained in Example 1, by mixing.

[0156] The mixture thus obtained was stirred reduced (20 mbar, i.e. 2000 Pa) for 15 minutes before the composition thus obtained was packaged in an aluminum cartridge.

[0157] Measurement of the breaking strength and the elongation at break by tensile testing was performed according to the protocol described below.

[0158] The measurement principle consists in drawing in a tensile testing machine, the mobile jaw of which moves at a constant speed equal to 100 mm/minute, a standard specimen formed from the crosslinked adhesive composition and in recording, at the time when the specimen breaks, the applied tensile stress (in MPa) and the elongation of the specimen (in %).

[0159] The standard specimen is dumbbell-shaped, as illustrated in international standard ISO 37. The narrow part of the dumbbell used has a length of 20 mm, a width of 4 mm and a thickness of 500 m.

[0160] To prepare the dumbbell, the composition packaged as described previously was heated to 100 C., and the amount required to form a film with a thickness of 300 m on an A4 sheet of silicone paper was then extruded thereon and left for 7 days at 23 C. and 50% relative humidity for crosslinking. The dumbbell is then obtained by simply cutting out from the crosslinked film.

[0161] The dumbbell of the adhesive composition then has a breaking stress of 8 MPa with an elongation at break of 10%. This test is repeated twice and gives the same result.

[0162] The adhesive composition was then subjected to tests of bonding of two strips of wood (each 20 mm20 mm2 mm in size) to give, after crosslinking for 7 days at 23 C., a breaking force of 2 MPa in adhesive rupture.