Dual-cure cationically polymerisable composition and method for producing a coating or a composite material implementing said composition

Abstract

In a first aspect, the present invention concerns a kit for a polymerizable composition comprising a portion A constituted by a composition comprising at least one monomer (a1) that is reactive towards a cationic species (b) or a Lewis or Brnsted acid species, and at least one co-initiator, and a portion B comprising at least one cationic salt (e) selected from the salts with formula S1, S3, and S4 shown and defined in claim 1. In a second aspect, the present invention concerns a method of producing a coating or a composite material starting from polymerizable composition comprising at least one salt (e) selected from the salts with formula S1, S2, S3, and S4 shown and defined in claim 10, said composition being polymerized without adding external heat thereto.

Claims

1. A kit for a polymerisable composition, said kit comprising: I. a first portion A constituted by a composition comprising at least one monomer a1 that is reactive towards a cationic species or a Lewis or Brnsted acid species, and at least one co-initiator b; II. a second portion B comprising at least one cationic salt e selected from the salts with formula S1, S3, and S4 below; ##STR00002## in which X represents a carbon atom or a sulfur atom; Y represents one or more stabilizing anionic species for the cationic species of the salt S1, or S3, or S4; R.sub.1 to R.sub.6, independently of one another, are selected from the following atom or atoms or group or groups, alone or in combination: a hydrogen atom; a nitro group NO.sub.2; a cyano group CN; a halogen atom; a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkyl group substituted with one or more group(s) or one or more atom(s) selected independently from list I comprising the following groups or atoms: hydroxyl; carbonyl, alkenyl, aryl, heteroaryl, ether, ester, aldehyde, ketone, carboxylic acid, a halogen atom, primary amine, secondary amine, tertiary amine, primary amide, secondary amide, tertiary amide, urea, thioester, thiocarbonate, sulfoxide, sulfone, phosphine, phosphorane, phosphine oxide, cycloalkyl, heterocycloalkyl, or combinations thereof; a C.sub.1-C.sub.20 alkoxy group, a C.sub.1-C.sub.20 alkoxy group substituted with a C.sub.1-C.sub.20 alkyl group; a C.sub.1-C.sub.20 alkoxy group substituted with a C.sub.1-C.sub.20 alkyl group and one or more group(s) or one or more atom(s) selected equally well from list I; a C.sub.1-C.sub.20 alkoxy group substituted with one or more group(s) or one or more atom(s) selected equally well from list I, an aryl group; a heteroaryl group; a cycloalkyl group; a heterocycloalkyl group; an aryl group substituted with one or more group(s) independently selected from list I; an heteroaryl group substituted with one or more group(s) independently selected from list I; an heterocycloalkyl group substituted with one or more group(s) independently selected from list I; a cycloalkyl group substituted with one or more group(s) independently selected from list I; an acyl group; an aroyl group; an alkoxycarbonyl group; a carbamyl group.

2. The kit according to claim 1, wherein the reactive monomer a1, is selected or includes at least one group selected from the list constituted by cyclic ethers; cyclic acetals; cyclic amines; cyclic iminoethers; cyclic sulfides; vinyls; cyclic esters; cyclic amides; cycloalkyls substituted with at least one phosphorus atom; and cyclic siloxanes.

3. The kit according to claim 1, wherein the monomer a1 is or includes a (C.sub.3-C.sub.20 (hetero)cycloalkyl).sub.n group, with 1n5, n being an integer, said (hetero)cycloalkyl(s) being saturated or unsaturated and comprising, in at least one cycle, at least one function or one or more atom(s) or a group selected from the list constituted by: an ether group; an oxygen atom; two oxygen atoms; three oxygen atoms; a primary amine; a secondary amine; a tertiary amine; a primary amide; a secondary amide; a tertiary amide; an ester group; a carbonate group; an orthoester group; a OSiO function; a vinylether function (OCHCH.sub.2); a halogen atom and a sulfur atom.

4. The kit according to claim 1, wherein the reactive monomer a1 is selected from cycloaliphatic epoxies.

5. The kit according to claim 1, wherein the co-initiator b is selected from or includes at least one group selected from list II constituted by: hydrogen peroxide; water; a C.sub.1-C.sub.20 alkyl group substituted with a hydroperoxide group OOH and with a thiol group SH; a C.sub.1-C.sub.20 alkyl group substituted with a hydroperoxide group OOH; a C.sub.1-C.sub.20 alkyl group substituted with a thiol group SH; a C.sub.1-C.sub.20 haloalkyl group substituted with a hydroperoxide group OOH and with a thiol group SH; a C.sub.1-C.sub.20 haloalkyl group substituted with a hydroperoxide group OOH; a C.sub.1-C.sub.20 haloalkyl group substituted with a thiol group SH; a C.sub.1-C.sub.20 aryl group substituted with a hydroperoxide (OOH) and with a thiol group (SH); a C.sub.1-C.sub.20 aryl group substituted with a hydroperoxide (OOH), a C.sub.1-C.sub.20 aryl group substituted with a thiol group (SH), a C.sub.1-C.sub.20 heteroaryl group substituted with a hydroperoxide (OOH) and with a thiol group (SH); a C.sub.1-C.sub.20 heteroaryl group substituted with a hydroperoxide (OOH); a C.sub.1-C.sub.20 heteroaryl group substituted with a thiol group (SH); a C.sub.1-C.sub.20 cycloalkyl group substituted with a hydroperoxide (OOH) and with a thiol group (SH); a C.sub.1-C.sub.20 cycloalkyl group substituted with a hydroperoxide (OOH); a C.sub.1-C.sub.20 cycloalkyl group substituted with a thiol group (SH); a C.sub.1-C.sub.20 heterocycloalkyl group substituted with a hydroperoxide (OOH) and with a thiol group (SH); a C.sub.1-C.sub.20 heterocycloalkyl group substituted with a hydroperoxide (OOH); a C.sub.1-C.sub.20 heterocycloalkyl group substituted with a thiol group (SH); an alkenyl group; an alkenyl group including at least one ether group.

6. The kit according to claim 1, wherein the proportion by weight of salt e relative to the weight of the final polymerisable composition comprising the first and second portions A and B is in the range 0.10% to 5%.

7. The kit according to claim 1, wherein the proportion by weight of the co-initiator relative to the weight of the final polymerisable composition comprising the first and second portions A and B is in the range 0.10% to 5%.

8. A polymerisable composition, comprising: at least one monomer a1 that is reactive towards a cationic species or a Lewis or Brnsted acid species; at least one co-initiator b; at least one cationic salt e selected from the salts with formula S1, S3, and S4 below; ##STR00003## in which X represents a carbon atom or a sulfur atom; Y represents one or more stabilizing anionic species for the cationic species of the salt S1 or S3, or S4; R.sub.1 to R.sub.6, independently of one another, are selected from the following atom or atoms or group or groups, alone or in combination: a hydrogen atom; a nitro group NO.sub.2; a cyano group CN; a halogen atom; a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkyl group substituted with one or more group(s) or one or more atom(s) selected independently from list I comprising the following groups or atoms: hydroxyl; carbonyl, alkenyl, aryl, heteroaryl, ether, ester, aldehyde, ketone, carboxylic acid, a halogen atom, primary amine, secondary amine, tertiary amine, primary amide, secondary amide, tertiary amide, urea, thioester, thiocarbonate, sulfoxide, sulfone, phosphine, phosphorane, phosphine oxide, cycloalkyl, heterocycloalkyl, or combinations thereof; a C.sub.1-C.sub.20 alkoxy group, a C.sub.1-C.sub.20 alkoxy group substituted with a C.sub.1-C.sub.20 alkyl group; a C.sub.1-C.sub.20 alkoxy group substituted with a C.sub.1-C.sub.20 alkyl group and one or more group(s) or one or more atom(s) selected equally well from list I; a C.sub.1-C.sub.20 alkoxy group substituted with one or more group(s) or one or more atom(s) selected equally well from list I, an aryl group; a heteroaryl group; a cycloalkyl group; a heterocycloalkyl group; an aryl group substituted with one or more group(s) independently selected from list I; an heteroaryl group substituted with one or more group(s) independently selected from list I; an heterocycloalkyl group substituted with one or more group(s) independently selected from list I; a cycloalkyl group substituted with one or more group(s) independently selected from list I; an acyl group; an aroyl group; an alkoxycarbonyl group; a carbamyl group.

9. A method of producing a coating or a composite material, comprising the following steps: (i) providing a first portion A constituted by a composition comprising at least one monomer a1 that is reactive towards a cationic species or a Lewis or Brnsted acid species, and at least one co-initiator b; and a second portion B comprising at least one cationic salt e selected from the salts with formula S1, S2, S3, and S4 below; ##STR00004## in which X represents a carbon atom or a positively charged heteroatom other than nitrogen; Y represents one or more stabilizing anionic species for the cationic species of the salt S1, or S2, or S3, or S4; R.sub.1 to R.sub.6, independently of one another, are selected from the following atom or atoms or group or groups, alone or in combination: a hydrogen atom; a nitro group NO.sub.2; a cyano group CN; a halogen atom; a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkyl group substituted with one or more group(s) or one or more atom(s) selected independently from list I comprising the following groups or atoms: hydroxyl; carbonyl, alkenyl, aryl, heteroaryl, ether, ester, aldehyde, ketone, carboxylic acid, a halogen atom, primary amine, secondary amine, tertiary amine, primary amide, secondary amide, tertiary amide, urea, thioester, thiocarbonate, sulfoxide, sulfone, phosphine, phosphorane, phosphine oxide, cycloalkyl, heterocycloalkyl, or combinations thereof; a C.sub.1-C.sub.20 alkoxy group, a C.sub.1-C.sub.20 alkoxy group substituted with a C.sub.1-C.sub.20 alkyl group; a C.sub.1-C.sub.20 alkoxy group substituted with a C.sub.1-C.sub.20 alkyl group and one or more group(s) or one or more atom(s) selected equally well from list I; a C.sub.1-C.sub.20 alkoxy group substituted with one or more group(s) or one or more atom(s) selected equally well from list I, an aryl group; a heteroaryl group; a cycloalkyl group; a heterocycloalkyl group; an aryl group substituted with one or more group(s) independently selected from list I; an heteroaryl group substituted with one or more group(s) independently selected from list I; an heterocycloalkyl group substituted with one or more group(s) independently selected from list I; a cycloalkyl group substituted with one or more group(s) independently selected from list I; an acyl group; an aroyl group; an alkoxycarbonyl group; a carbamyl group; and the mixture of the first and second portions A and B in order to form a polymerisable composition; and wherein the at least one co-initiator b is selected such that it reacts with the at least one cationic salt e in an exothermic reaction; (ii) applying said polymerisable composition in one or more layers to a substrate or impregnating a reinforcement with said polymerisable composition; and (iii) polymerising said at least one monomer a1 under the action of a cation or of a Lewis or Brnsted acid species formed by the salt e under the action of said at least one co-initiator b, without adding external heat to said polymerisable composition, in order to form a coating or a composite material.

10. The method according to claim 9, wherein the step (iii) is carried out at a temperature in the range 10 C. to 30 C.

11. The kit according to claim 1 wherein the second portion B comprises at least one monomer a2 that is reactive towards a cationic species or a Lewis or Brnsted acid species.

12. The kit according to claim 1 wherein Y comprises at least one anionic species selected, alone or in combination, from Br, Cl, BF4-, PF6-, AsF6-, AnF6-, SbF6-, SnF6-, ClO4-, sulfonates.

13. The kit according to claim 1 wherein R.sub.1 to R.sub.6, independently of one another, are selected from atom(s) or group(s), alone or in combination which is/are arranged so as to carry one or more positive charges.

14. The kit according to claim 6 wherein the proportion by weight of salt e relative to the weight of the final polymerisable composition comprising the first and second portions A and B is in the range 0.5% to 3%.

15. The kit according to claim 7, wherein the proportion by weight of the co-initiator b relative to the weight of the final polymerisable composition comprising the first and second portions A and B is in the range 0.5% to 3%.

16. The polymerisable composition according to claim 8 wherein said composition comprises at least monomer a2 that is reactive towards a cationic species or a Lewis or Brnsted acid species, and at least one polymerisation rate regulating agent d.

17. The method according to claim 9 wherein the step (iii) is done also under the action of radiation or electron bombardment.

18. The method according to claim 9, wherein the coating has a thickness of more than 1 mm.

19. A kit for a polymerisable composition, the kit comprising: I. a first portion A constituted by a composition comprising at least one monomer a1 that is reactive towards a cationic species or a Lewis or Brnsted acid species, and at least one co-initiator b; II. a second portion B comprising at least one cationic salt e S1 below; ##STR00005## in which X represents a positively charged heteroatom other than nitrogen; Y represents one or more stabilizing anionic species for the cationic species of the salt S1; R.sub.2 to R.sub.6, independently of one another, are selected from the following atom or atoms or group or groups, alone or in combination: a hydrogen atom; a nitro group NO.sub.2; a cyano group CN; a halogen atom; a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkyl group substituted with one or more group(s) or one or more atom(s) selected independently from list I comprising the following groups or atoms: hydroxyl; carbonyl, alkenyl, aryl, heteroaryl, ether, ester, aldehyde, ketone, carboxylic acid, a halogen atom, primary amine, secondary amine, tertiary amine, primary amide, secondary amide, tertiary amide, urea, thioester, thiocarbonate, sulfoxide, sulfone, phosphine, phosphorane, phosphine oxide, cycloalkyl, heterocycloalkyl, or combinations thereof; a C.sub.1-C.sub.20 alkoxy group, a C.sub.1-C.sub.20 alkoxy group substituted with a C.sub.1-C.sub.20 alkyl group; a C.sub.1-C.sub.20 alkoxy group substituted with a C.sub.1-C.sub.20 alkyl group and one or more group(s) or one or more atom(s) selected equally well from list I; a C.sub.1-C.sub.20 alkoxy group substituted with one or more group(s) or one or more atom(s) selected equally well from list I, an aryl group wherein at most two groups among R.sub.2 to R.sub.6 are an aryl group; a heteroaryl group; a cycloalkyl group; a heterocycloalkyl group; an aryl group substituted with one or more group(s) or one or more atom(s) independently selected from the list comprising the following groups or atoms: hydroxyl; carbonyl, alkenyl, aryl, wherein at most two groups amount R.sub.2 to R.sub.6 are an aryl group, heteroaryl, ester, aldehyde, ketone, carboxylic acid, a halogen atom, primary amine, secondary amine, tertiary amine, primary amide, secondary amide, tertiary amide, urea, thioester, thiocarbonate, sulfoxide, sulfone, phosphine, phosphorane, phosphine oxide, cycloalkyl, heterocycloalkyl, or combinations thereof; a heteroaryl group substituted with one or more group(s) or one or more atom(s) independently selected from list I; a heterocycloalkyl group substituted with one or more group(s) or one or more atom(s) independently selected from list I; a cycloalkyl group substituted with one or more group(s) or one or more atom(s) independently selected from list I; an acyl group; an aroyl group; an alkoxycarbonyl group; a carbamyl group.

20. A kit for a polymerisable composition, said kit comprising: I. a first portion A constituted by a composition comprising at least one monomer a1 that is reactive towards a cationic species or a Lewis or Brnsted acid species, and at least one co-initiator b; II. a second portion B comprising at least one cationic salt e selected from the salts with formula S1, S3, and S4 below; ##STR00006## in which X represents a carbon atom or a sulfur atom; Y represents one or more stabilizing anionic species for the cationic species of the salt S1, or S3, or S4; R.sub.1 to R.sub.6, independently of one another, are selected from the following atom or atoms or group or groups, alone or in combination: a hydrogen atom; a nitro group NO.sub.2; a cyano group CN; a halogen atom; a C.sub.1-C.sub.20 alkyl group, a C.sub.1-C.sub.20 alkyl group substituted with one or more group(s) or one or more atom(s) selected independently from list I comprising the following groups or atoms: hydroxyl; carbonyl, alkenyl, aryl, heteroaryl, ether, ester, aldehyde, ketone, carboxylic acid, a halogen atom, primary amine, secondary amine, tertiary amine, primary amide, secondary amide, tertiary amide, urea, thioester, thiocarbonate, sulfoxide, sulfone, phosphine, phosphorane, phosphine oxide, cycloalkyl, heterocycloalkyl, or combinations thereof; a C.sub.1-C.sub.20 alkoxy group, a C.sub.1-C.sub.20 alkoxy group substituted with a C.sub.1-C.sub.20 alkyl group; a C.sub.1-C.sub.20 alkoxy group substituted with a C.sub.1-C.sub.20 alkyl group and one or more group(s) or one or more atom(s) selected equally well from list I; a C.sub.1-C.sub.20 alkoxy group substituted with one or more group(s) or one or more atom(s) selected equally well from list I, an aryl group; a heteroaryl group; a cycloalkyl group; a heterocycloalkyl group; an aryl group substituted with one or more group(s) independently selected from list I; a heteroaryl group substituted with one or more group(s) independently selected from list I; a heterocycloalkyl group substituted with one or more group(s) independently selected from list I; a cycloalkyl group substituted with one or more group(s) independently selected from list I; an acyl group; an aroyl group; an alkoxycarbonyl group; a carbamyl group; and wherein the first portion A includes a polymerization rate regulating agent d that is or includes: a C.sub.3-C.sub.6 heteroaryl wherein at least one atom of the heterocycle is nitrogen, said heterocycle being substituted with group(s) selected among: one or more C.sub.3-C.sub.6 aryl group(s); one or more C.sub.3-C.sub.6 aryl group(s) and with one or more C.sub.1 to C.sub.10 alkyl chains, and one or more C.sub.1 to C.sub.10 alkyl chains; a C.sub.3-C.sub.6 aryl group substituted with: a primary amine, a secondary amine, a tertiary amine; and/or with a C.sub.3-C.sub.6 aryl group; and/or with one or more C.sub.1 to C.sub.10 alkyl chains.

Description

DETAILED DESCRIPTION OF THE FIGURES

(1) FIG. 1 shows the reaction mechanism between a cationic salt (e) and a cationic species or Lewis or Brnsted acid;

(2) FIGS. 2 and 3 show three thermometric curves measured for examples of polymerisable compositions in accordance with the invention;

(3) FIGS. 4A, 4B and 4C show examples of cationic salts S4(1), S4(2) and S4(3) in accordance with the invention; and

(4) FIGS. 5, 6, 7 and 8 show thermometric curves measured for examples of polymerisable compositions in accordance with the invention;

(5) FIG. 9 shows a first series of thermometric curves measured at different thicknesses in a polymerisable composition in accordance with the invention and a second series of thermometric curves measured at different thicknesses in a reference polymerisable composition;

(6) FIG. 10 shows values for the flexural modulus (GPa) (ISO standard 178: 2010) obtained for industrial matrices, high performance matrices and a matrix in accordance with the invention;

(7) FIG. 11 shows the values obtained for the maximum stress as a function of the percentage deformation (ISO standard 178:2010) for industrial matrices, high performance matrices, and a matrix in accordance with the invention.

DETAILED DESCRIPTION OF EMBODIMENTS

(8) The invention can be better understood from the following exemplary embodiments presented below as non-limiting examples. The conversion kinetics of the oxirane bonds were monitored using Fourier transform infrared spectroscopy, which allowed the polymerisation process to be monitored in real time.

(9) Lists of compounds employed in the polymerisable compositions described in Tables 1 to 4 below and in paragraphs I to IV: reactive monomer (a): dicycloaliphatic epoxy, in particular (3,4-epoxycyclohexane) methyl 3,4-epoxycyclohexanecarboxylate (a1), such as Uvacure 1500; (3,4-epoxycyclohexane) methyl 3,4-epoxycyclohexanecarboxylate (a11), such as UVACURE 6110; an oxetane monomer (OXT-101, 3-methyl-3-oxetanemethanol) (a111); cationic salts (e): cationic salt S1(1) in which X: O; R.sub.2, R.sub.4 and R.sub.6: C.sub.6H.sub.5, R.sub.3 and R.sub.5: H, YBF.sub.4.sup.; cationic salt S1(2) in which X: O, R.sub.2 and R.sub.4 and R.sub.6: CH.sub.3, R.sub.3 and R.sub.5: H, YBF.sub.4.sup.; cationic salt S1(3) in which X: O, R.sub.2 and R.sub.4 and R.sub.6: C.sub.6H.sub.5Cl, R.sub.3 and R.sub.5: H, YBF.sub.4.sup.; cationic salt S1(4) in which X: O, R.sub.2 and R.sub.4 and R.sub.6: C.sub.6H.sub.5OCH.sub.3, R.sub.3 and R.sub.5: H, YBF.sub.4.sup.; cationic salt S1(5) in which X: O, R.sub.2: CH3, R.sub.4 and R.sub.6: C.sub.6H.sub.5, R.sub.3 and R.sub.5: H, YBF.sub.4.sup.; cationic salt S1(6) in which X: O, R.sub.2 and R.sub.6: C.sub.6H.sub.5, R.sub.4: CH.sub.3, R.sub.3 and R.sub.5: H, YBF.sub.4.sup.; cationic salt S1(7) in which X: O, R.sub.2 and R.sub.6: C.sub.6H.sub.5, R.sub.4: C.sub.6H.sub.5OH, R.sub.3 and R.sub.5: H, YBF.sub.4.sup.; cationic salt S1(8) in which X: O, R.sub.2 and R.sub.6: C.sub.6H.sub.5, R.sub.4: C.sub.6H.sub.5(CH.sub.2)2OH, R.sub.3 and R.sub.5: H, YBF.sub.4.sup.; cationic salt S2(1) in which R.sub.2, R.sub.4 and R.sub.6: C.sub.6H.sub.5, R.sub.3 and R.sub.5: H, Y: BF.sub.4.sup.; cationic salt S3(1) in which R.sub.2, R.sub.3, R.sub.5 and R.sub.6: H, and R.sub.4: Br, YBF.sub.4.sup.; and the salts S4(1), S4(2) and S4(3) shown in FIG. 4. The substituents on the benzene rings were in the para position. Each of said salts (e), previously dissolved to approximately 25% by weight in a solvent, in particular propylene carbonate, was present in an amount of 3% by weight relative to the total weight of the polymerisable composition; co-initiators (b): hydrogen peroxide (H.sub.2O.sub.2) (b1); isobutylvinylether (b2); 4-mercaptophenol (b3); photosensitizer (c): phenothiazine (c1).
IVarious Polymerisable Compositions in Accordance with the Invention were Subjected to Irradiation without Adding External Heat to Said Compositions (i.e. at Ambient Temperature)

(10) The proportion by weight of cationic salt relative to the total weight of the polymerisable composition (in this case 1 gram (g)) was 3%, regardless of whether the salt was S1(1), the salt S3(1) or Irgacure 250, which is an iodonium salt.

(11) The proportions by weight of the co-initiator (b1) and of the co-initiator (b2) relative to the total weight of the polymerisable composition were respectively 3% and 1%.

(12) The proportion by weight of photosensitizer (C1) relative to the total weight of the polymerisable composition was 1%.

(13) The irradiation lamp was a Hamamatsu HgXe lamp with a 365 nm reflector and a power of 40 milliwatts per square centimeter (mW/cm.sup.2). The polymerisable composition was applied to a substrate, in this example a KBr pellet, in the form of a single layer with a thickness of 20 micrometers (m).

(14) The maximum rates of polymerisation (Rp) as well as the conversions (x %) after 400 seconds irradiation under the HgXe lamp obtained are contained in Table 1 below.

(15) TABLE-US-00001 TABLE 1 Final Rp conversion Example (a) (b) (c) (e) (mol .Math. l.sup.1 .Math. s.sup.1) degree (%) 1 (a1) S1(1) 0.19 75 2 (a1) (c1) S1(1) 0.11 100 3 (a1) (b1) S1(1) 0.38 93 4 (a1) (b2) S1(1) 0.29 87 5 (a1) S3(1) 0.054 65 6 (a1) (b1) S3(1) 0.059 64 7 (a1) (b2) S3(1) 0.059 70 8 (a1) Irgacure 0.64 60 250

(16) The high efficiency of the salt S1(1) alone should be noted; it reached a degree of conversion of approximately 75% in less than 400 seconds of irradiation. This efficiency was accentuated by the presence of a photosensitizer (c1) or indeed a co-initiator (b1) or (b2).

(17) The salt S3(1) was less reactive under irradiation, but it reached degrees of conversion that were higher than the degree of conversion of the iodonium salt (Irgacure 250) after 400 seconds (s) of irradiation.

(18) IIStudy of the Impact of Different Structures of Cationic Salts S1 in Accordance with the Invention on the Rate of Polymerisation Rp and the Final Degree of Conversion (%) in the Absence of Co-Initiator (b), without Adding External Heat to Said Compositions, (i.e. at Ambient Temperature)

(19) The proportion by weight of cationic salt relative to the total weight of the polymerisable composition (in this case 1 g) was 3%, regardless of whether it was for the salts S1(1) to S1(6), or Irgacure 250, which is an iodonium salt. The irradiation lamp was a Hamamatsu HgXe lamp with a 365 nm reflector and a power of 40 mW/cm.sup.2.

(20) The polymerisable composition was applied to a substrate, in this example a KBr pellet, in the form of a single layer with a thickness of 20 m.

(21) TABLE-US-00002 TABLE 2 Final Rp conversion Example (a) (e) (mol .Math. l.sup.1 .Math. s.sup.1) degree (%) 9 (a1) S1(1) 0.19 75 10 (a1) S1(2) 0.01 20 11 (a1) S1(3) 0.23 57 12 (a1) S1(4) 0.08 97 13 (a1) S1(5) 0.01 11 14 (a1) S1(6) 0.03 35 15 (a1) S1(7) 0.04 89 8 (a1) Irgacure 0.64 60 250
IIIThermometric Measurements Carried Out on Various Polymerisable Compositions in Accordance with the Invention Polymerised in the Absence of Irradiation, Said Compositions Including a Co-Initiator (b), without Adding External Heat to Said Compositions, (i.e. at Ambient Temperature)

(22) The proportion by weight of cationic salt relative to the total weight of the polymerisable composition (in this case 1 g) was 3%. The proportions by weight of the co-initiators (b1), (b2) and (b3) relative to the total weight of the polymerisable composition were respectively 1%, 3%, and 3%.

(23) FIG. 2 shows three thermometric curves obtained from a K type thermocouple in the polymerisable compositions with references (A), (B) and (C) all comprising at least one reactive monomer (a1), a cationic salt S1(1) and a co-initiator, respectively (b1), (b2) and (b3). It can thus be observed from said curves that an efficient thermal polymerisation can be accompanied by the release of a large amount of heat. FIG. 3 shows two thermometric curves obtained from a type K thermocouple immersed in the polymerisable compositions with references (D) and (E), each comprising a reactive monomer (a1), a cationic salt S3(1) and a co-initiator, respectively (b1) and (b2).

(24) Thermal polymerisation for the polymerisable compositions examples (D) and (E) was also observed, but with a much stronger exothermic reaction than with the co-initiator (b1).

(25) IVMeasurements of Gelling Times (Min) Carried Out on Polymerisable Compositions Including Different Cationic Salts in Accordance with the Invention Polymerised in the Absence of Irradiation, without Adding External Heat to Said Compositions, (i.e. at Ambient Temperature), Said Polymerisable Compositions Including a Co-Initiator (b)

(26) The gelling times were calculated from the thermometric curves obtained as described above in point III. The gelling times corresponded to the maximum of the exothermic polymerisation peak.

(27) Table 3 below sets out the gelling times obtained for various cationic salts in combination with various co-initiators (b). The proportion by weight of cationic salt relative to the total weight of the polymerisable composition (in this case 1 g) was 3%, regardless of whether it was for the salt S1(1), the salt S2(1), the salt S3 (1) or the salts S4 (1) (2) (3). The proportions by weight of the co-initiator (b1) and of the co-initiator (b2) relative to the total weight of the polymerisable composition were respectively 1% and 3%.

(28) TABLE-US-00003 TABLE 3 Gelling times Examples (a) (e) (b) (min) 20 (a1) S1(1) (b1) 15 21 (a1) S1(1) (b2) 6 30 (a1) S1(3) (b1) 10 22 (a1) S2(1) (b1) 360 23 (a1) S2(1) (b2) >600 24 (a1) S3(1) (b1) 10 25 (a1) S3(1) (b2) 20 26 (a1) S4(1) (2) (3) (b1) Instantaneous

(29) The structure of the co-initiator (b) meant that the rate of polymerisation could be adjusted, as demonstrated in Table 4 below.

(30) TABLE-US-00004 TABLE 4 Gelling Examples (a) (e) (b) times (min) 27 (a1) S1(1) ROOH with 2 R: ClC.sub.6H.sub.5CO 28 (a1) S1(1) ROOH with 6 R: CH.sub.3CO 31 (a1) S1(1) R.sub.zOCHCH.sub.2 25 R.sub.z: (CH.sub.3).sub.2CH.sub.2) 32 (a1) S1(1) R.sub.zOCHCH.sub.2 16 R.sub.z: CH.sub.3(CH.sub.2).sub.2 33 (a1) S1(1) R.sub.zOCHCH.sub.2 12 R.sub.z: CH.sub.3CH.sub.2 34 (a1) S1(1) R.sub.zOCHCH.sub.2 6 R.sub.z: (CH.sub.2).sub.2OH 35 (a1) S1(1) ROOH 45 R: C.sub.6H.sub.5 36 (a1) S1(1) ROOH 45 R: (CH.sub.3).sub.3C 29 (a1) S3(1) ROOH >600 R: (CH.sub.3).sub.3C

(31) The gelling times were measured for the polymerisable compositions of Example 9 (S1(1)), 11 (S1(3)) and 12 (S1(4)) described above in point I and each including hydrogen peroxide as the co-initiator (b1), in the absence of irradiation. These gelling times were: <<60 minutes, of the order of 15 minutes, and of the order of 12 minutes respectively for those of Example 9 (S1(1)), 11 (S1 (3)) and 12 (S1(4)).

(32) The high efficiency of the S1/ROOH pair (with RClC.sub.6H.sub.5CO) or OCHCH.sub.2) should be noted. The gelling times were adjustable (a few minutes to several hours) by adjusting the nature of the co-initiator, the nature of the substituents carried by these co-initiators as well as the structure of the cationic salt.

(33) FIG. 5 shows three thermometric curves: the first curve (F) corresponds to Example 20, which did not contain a polymerisation rate regulating agent (d); the second curve (G) corresponds to Example 20 to which 1% by weight of N-vinylcarbazole (d1) relative to the total weight of the polymerisable composition had been added; the third curve (H) corresponds to Example 20 to which 1% by weight of N,N-dimethylaniline (d2) relative to the total weight of the polymerisable composition had been added. It should also be noted that, following the addition of (d1) or (d2), the gelling times were displaced by almost 30 minutes. It is thus possible to adjust the rate of initiation.

(34) FIG. 6 shows six thermometric curves: the first curve (I) corresponds to Example 20, which did not include polymerisation rate regulating agent (d); the curves (J), (K), (L), (M) and (N) correspond to Example 20 to which 0.5%, 1%, 1.5%, 3% and 6% by weight respectively of 2,6-di-tert-butylpyridine (d3) relative to the total weight of the polymerisable composition had been added.

(35) A shift of the gelling times as a function of the proportions of the agent (d3) was thus observed, with a substantial exothermic release of heat when the proportion of agent (d3) reached 6% by weight.

(36) VPolymerisation of Aromatic or Aliphatic Epoxy Resins Including One or More Oxetane Groups as the Reactive Monomer (a1), Under Irradiation and Combined with a Co-Initiator (b) in a Dual-Cure System, without Adding External Heat to Said Compositions, (i.e. at Ambient Temperature).

(37) FIG. 7 shows a thermometric curve (O) corresponding to a polymerisable composition comprising 1,2-epoxy-3-phenoxypropane (sold by SIGMA-ALDRICH) as the reactive monomer (a1), isobutylvinylether as the co-initiator (b2), and a cationic salt S1(1). It should be noted that the reaction was of low exothermicity.

(38) By way of comparison, FIG. 8 shows two curves (P) and (Q) representing the exotherms of the surface and the core respectively in the layer to be polymerised. The polymerisable composition employed in FIG. 8 corresponded to Example 21. An exothermic peak at 70 C. should be noted, which was much higher than the exothermic peak of the order of 19.5 C. shown in FIG. 7.

(39) Cationic polymerisation, under irradiation or via a thermal pathway, i.e. at ambient temperature, of aromatic or aliphatic epoxy resins is less effective than for cycloaliphatic epoxy resins.

(40) VIPhotopolymerisation at Depth of a Polymerisable Composition in Accordance with the Invention Compared with a Reference Polymerisable Under Irradiation and Combined with a Co-Initiator (b) in a Dual-Cure System, without Adding External Heat to Said Compositions, (i.e. at Ambient Temperature)

(41) The polymerisable composition in accordance with the invention (Example 37) comprised a mixture of monomers: 92.5% of (a11) for 7.5% of (a111); and a salt S1(1) and a co-initiator (b2) in an amount of 3% and 1.5% by weight respectively relative to the total weight of the composition (in this case 5 g), the remainder being formed by the mixture of monomers. The reference composition (Example 38) comprised the same mixture of monomers as Example 37; and an Irgacure 250 salt and a co-initiator (b2) respectively in an amount of 3% and 1.5% by weight relative to the total weight of the composition, the remainder being formed by the mixture of monomers.

(42) The photopolymerisation at depth was monitored by thermometry. Each polymerisable composition was placed in a test tube produced from plastic material which had previously been perforated over the length in order to accommodate thermocouples at predetermined depths on the tube (at the surface; 8 mm; 16 mm; 24 mm; 32 mm and 40 mm). Irradiation of the mixture of monomers was carried out at the level of the opening to the tube, which was covered with a glass plate, using a lamp (UV Hammamatsu lamp with 365 nm reflector) disposed at a distance of approximately 2 cm above the glass plate. The glass plate absorbed the infrared radiation produced by the lamp. In this manner, the temperature detected by the surface thermocouple would solely be from the photopolymerisation reaction.

(43) The first series (R) of thermometric curves corresponding to the polymerisable composition in accordance with the invention (Example 37) and the second series of thermometric curves (S) corresponding to the reference polymerisable composition (Example 38) were very different.

(44) Concerning Example 38 (reference), the temperature increased rapidly at the surface due to the photopolymerisation reaction in the mixture of monomers. The curve associated with the thermocouple located 8 mm below the surface fairly rapidly followed the same profile as the curve associated with the surface thermocouple. The curves associated with the thermocouples located at more than 8 mm were very different, since it can be seen that the temperature measured in the polymerisable composition 38 dropped. In this case, photopolymerisation at depth occurred in accordance with a process of thermal transfer/diffusion, the heat generated at the surface only propagating to a small extent into the thickness. Curing at depth (beyond 8 mm) was thus incomplete.

(45) Concerning Example 37 (composition in accordance with the invention), the surface temperature also increased rapidly for the same reasons as those given for Example 38. However, the profile for the curve associated with the surface thermocouple and the curves associated with the other thermocouples were almost identical throughout the thickness of the composition 37 (40 mm). In this case, photopolymerisation at depth occurred along a polymerisation front, changing the polymer, polymerised and hot, into a mixture of liquid polymers that were thus not polymerised and cold. The fact that the maximum temperature was the same throughout the thickness means that the polymerisable composition in accordance with the invention, 37, caused the polymerisation front to be self-sustainingthis is an essential element with photopolymerisation at depth without adding external heat.

(46) VIIComparison of the Mechanical Properties Obtained for a Polymerisable Composition in Accordance with the Invention, Example 39, (the Composition of which Corresponds to Example 21 Described Above) Compared with the Mean of the Values Obtained for Reference Polymerisable Compositions from the Prior Art.

(47) Table 5 below indicates the commercial names of reference compounds from the prior art (commercial reference of epoxy monomer/commercial reference of amine monomer), the implementation cycles and their applications.

(48) TABLE-US-00005 TABLE 5 Commercial name Implementation cycles Application DER 332/DEH 619 8 days at ambient temp. Industrial DER 331/DEH 2919 8 days at ambient temp. matrices Epikote 05475/ 5 min to 120 C. High Epikure 05443 performance Araldite LY 5052/ 1 day at ambient temp. matrices Aradur 5052 followed by thermal post- treatment of 4 h at 100 C. Or 4 h at 80 C. Araldite MY 0816/ 2 h at 100 C. followed by Aradur 976-1 two thermal post- treatments: 2 h at 150 C. and 2 h at 220 C. Araldite MY 0510/ 2 h at 150 C. followed by Aradur 976-1 two thermal post- treatments: 4 h at 180 C. + 2 h at 200 C. Araldite MY 720/ 2 h at 80 followed by Aradur 976-1 three thermal post- treatments: 1 h at 100 + 4 h at 150 + 7 h at 200 C.

(49) The polymerisable composition in accordance with the invention, Example 39, (the composition of which corresponds to Example 21) was polymerised for one day at ambient temperature without adding external heat to the composition 39. A step of thermal post-treatment applied to the thermoset matrix in order to reorganize the polymer chains that had been formed was carried out for 4 h at 100 C. The means of the values measured for the flexural moduluses in gigapascals (GPa) and for the maximum stresses in mega pascals (MPa) obtained for the industrial matrices, the high performance matrices and the matrix obtained from polymerisation of the polymerisable composition 39 are recorded in the accompanying FIGS. 10 and 11. Thus, it can be seen that the matrix obtained by cationic polymerisation of the composition 39 can be used to obtain highly satisfactory mechanical performances.

(50) VIIIComparison of Thermal Properties Obtained for Two Polymerisable Compositions in Accordance with the Invention

(51) Example 39 mentioned above (the composition of which corresponds to Example 21 described above) and Example 40, identical to Example 39 with the difference that no thermal post-treatment steps were carried out, were compared with the reference polymerisable compositions from the prior art described in Table 5.

(52) Table 6 below records the glass transition temperatures (T.sub.G) determined by DMA (dynamic mechanical analysis) for the prior art compositions, corresponding to those also indicated in Table 5, which had undergone the implementation cycles described in Table 5, as well as for the compositions in accordance with the invention (Examples 39 and 40). This Table 6 also records the decomposition temperatures (Td) determined by TGA (thermogravimetric analysis) for a prior art composition corresponding to that also indicated in Table 5 and which had undergone the implementation cycle described in Table 5, and for a composition in accordance with the invention corresponding to Example 40.

(53) TABLE-US-00006 TABLE 6 References for the polymerisable compositions T.sub.G ( C.) DER 332/DEH 619 77 C. Araldite CY 179/Aradur 917 189 C. Epikote/Epikure 127 C. Araldite LY 5052/Aradur 126 C. Araldite MY 0510/Aradure 191 C. Example 39 160-200 C..sup. Example 40 125 C. Td ( C.) Araldite CY 179/Aradur 917 372 C. Example 40 404 C.

(54) Advantageously, the polymerisable compositions in accordance with the invention could be used to obtain values for T.sub.G and Td that were similar, or even superior, to the prior art compositions.