Silicone hydrogel with composite hydrophilic and silicone polymers prepared with selective crosslink agents
View Patent ↗A synthetic route to polymers comprised of at least two monomers each with a very different reactivity ratio by using a corresponding crosslink agent for each monomer. Novel crosslink agents are described that provide for the copolymerization of at least one hydrophilic monomer with at least one lens monomer typically used to prepare materials for ophthalmic lenses. The new crosslink agents have a relatively high selectivity for the hydrophilic monomer and limited reactivity with the crosslink agent used to polymerize the lens monomer.
1. A silicone hydrogel polymer comprising the reaction product of two or more crosslink agents, a hydrophilic monomer and a silicone-containing lens monomer or macromer, wherein at least one of the two or more crosslink agents is selected from formula I or formula II
wherein R 1 , R 2 , R 3 , R 4 , R 7 and R 8 are independently selected from hydrogen, C 1 -C 4 alkyl, C 1 -C 2 alkanol or hydroxyl;
A is O, O(CH 2 CH 2 O) v or [SiR 5 R 6 O] w SiR 5 R 6 , wherein R 5 and R 6 are independently selected from C 1-4 -alkyl or phenyl, and v is from 1-20 and w is from 0 to 60;
m and n are integers independently selected from 1 to 10; p is 0 or 1; and q is an integer from 0 to 6; and
X and Y are independently selected from O or NR 9 , wherein R 9 is hydrogen, C 1 -C 4 alkyl or C 1 -C 2 alkanol; or
at least one of the two or more crosslink agents is selected from formula III
wherein R 1 , R 2 , A and p are defined above, and m is 1, 2 or 3; and n and n′ are integers independently selected from the integers 1 to 10; wherein
the hydrophilic monomer has a reactivity ratio R h =k hh /k nx and the crosslink agent of formula I, formula II or formula III has a reactivity ratio R x =k xx /k xh , wherein k hh , k hx , k xx and k xh are the propagation constants for the following radical polymerization reactions, and M h represents the hydrophilic monomer, M h * represents the hydrophilic monomer radical, M x represents the crosslink agent of formula I, II or III, and M x * represents the crosslink agent radical of general formula I, II, or III
M h *+M h →M h M h *k hh ;
M h *+M x →M h M x *k hx ;
M x *+M x →M x M x *k xx ;
M x *+M h →M x M h *k xh ; and
the ratio R h /R x is from 0.1 to 10,
the silicone containing lens monomer has a reactivity ratio R l =k ll /k ly and a second crosslink agent has a reactivity ratio R y =k yy /k yl , wherein k ll , k ly , k yy and k yl are the propagation constants for the following radical polymerization reactions, and M l represents the silicone-containing lens monomer, M l * represents the silicone-containing lens monomer radical, M y represents the second crosslink agent, and M y * represents the second crosslink agent radical,
M l *+M l →M l M l *k ll ;
M l *+M y →M l M y *k ly ;
M y *+M y →M y M y *k yy ;
M y *+M l →M y M l *k yl ; and
the ratio R l /R y is from 0.1 to 10, and
the hydrophilic monomer and the silicone containing lens monomer have a ratio, R H /R L , greater than 10 or less than 0.1,
wherein the propensity of the crosslink agents of formula I, II and III to polymerize with the hydrophilic monomer and the propensity of the second crosslink agent to polymerize with the silicone lens monomer provides a silicone hydrogel polymer for use as an ophthalmic lens.
2. A polymer of claim 1 , wherein the at least one of the crosslink agents is of formula I
3. The polymer of claim 2 wherein the hydrophilic monomer is selected from the group consisting of N-vinyl pyrrolidone, N-vinyl piperidone, N-vinyl-ε-caprolactam, N-vinylimidazolidone, N-vinylsuccinimide, N-vinylforamide and mixtures thereof.
4. The polymer of claim 3 further comprising a lens monomer selected from the group consisting of 2-hydroxyethyl methacrylate, tris-(trimethylsiloxy)-3-methacryloxypropylsilane, dimethylacrylamide, methacrylic acid, 2-phenylethyl acrylate, 2-phenoxyethyl acrylate, 2-phenoxyethyl methacrylate, isobornyl methacrylate, 2-methoxyethyl methacrylate, glycerol methacrylate, and any mixture thereof.
5. The polymer of claim 2 wherein the hydrophilic monomer is N-vinyl pyrrolidone.
6. A polymer of claim 1 , wherein the at least one of the crosslink agents is of formula II
7. The polymer of claim 6 wherein the hydrophilic monomer is selected from the group consisting of N-vinyl pyrrolidone, N-vinyl piperidone, N-vinyl-ε-caprolactam, N-vinylimidazolidone, N-vinylsuccinimide, N-vinylformamide and mixtures thereof.
8. The polymer of claim 7 further comprising a lens monomer selected from the group consisting of 2-hydroxyethyl methacrylate, tris-(trimethylsiloxy)-3-methacryloxypropylsilane, dimethylacrylamide, methacrylic acid, 2-phenylethyl acrylate, 2-phenoxyethyl acrylate, 2-phenoxyethyl methacrylate, 2-methoxyethyl methacrylate, glycerol methacrylate, and any mixture thereof.
9. A polymer of claim 1 , wherein the at least one of the crosslink agents is of formula III
10. The polymer of claim 9 wherein the hydrophilic monomer is selected from the group consisting of N-vinyl pyrrolidone, N-vinyl piperidone, N-vinyl-ε-caprolactam, N-vinylimidazolidone, N-vinylsuccinimide, N-vinylformamide and mixtures thereof.
11. The polymer of claim 10 further comprising a lens monomer selected from the group consisting of 2-hydroxyethyl methacrylate, tris-(trimethylsiloxy)-3-methacryloxypropylsilane, dimethylacrylamide, methacrylic acid, 2-phenylethyl acrylate, 2-phenoxyethyl acrylate, 2-phenoxyethyl methacrylate, isobornyl methacrylate, 2-methoxyethyl methacrylate, glycerol methacrylate, and any mixture thereof.
12. An ophthalmic lens comprising the polymer of claim 3 .
13. An ophthalmic lens comprising the polymer of claim 6 .
14. An ophthalmic lens comprising the polymer of claim 9 .