Polyquaternium-1 synthesis methods and associated formulations
View Patent ↗A multipurpose solution for contact lens care, comprising: an aqueous liquid medium; a quaternary ammonium polymer having an average molecular weight as determined by the proton NMR method of at least 28 k, and methods for making the same.
1. A multipurpose solution for contact lens care, comprising:
an aqueous liquid medium; and
from about 0.00001% to about 0.01% w/w of polyquaternium-1 having a number average molecular weight as determined by proton NMR of 28,000 or more.
2. The solution of claim 1 , wherein said polyquaternium-1 has a molecular weight of at least 34,000.
3. A multipurpose solution for contact lens care, comprising:
an aqueous liquid medium; and
from about 0.00001% to about 0.01% w/w of polyquaternium-1 obtained by a process of:
a) mixing 1,4-bis-dimethylamino-2-butene, water, a first portion of triethanolamine and a first portion of acid;
b) adding a 1,4-dichloro-2-butene and heating the reaction mixture;
c) adding a second portion of triethanolamine and a second portion of acid, and
d) isolating Polyquatemium-1 having a number average molecular weight as determined by proton NMR of 28,000 or more, at a yield of at least about 50%.
4. The solution of claim 3 , wherein polyquaternium-1 has a molecular weight of at least 34,000.
5. The solution of claim 3 , wherein the acid is selected from the group consisting of HCl, H 2 SO 4 and H 3 PO 4 .
6. The solution of claim 3 , wherein the acid is HCl.
7. The solution of claim 3 , wherein the 1,4-dichloro-2-butene is added drop-wise.
8. The method of claim 3 , wherein the molar ratio of 1,4-bis-dimethylamino-2-butene to triethanolamine is from about 10:1 to about 1:5.
9. The method of claim 3 , wherein the molar ratio of triethanolamine to acid in said first portion is from about 10:1 to about 1:10.
10. The method of claim 3 , wherein the molar ratio of triethanolamine to acid in said second portion is from about 10:1 to about 1:100.
11. The method of claim 3 , wherein the molar ratio of triethanolamine to acid in said first and second portions is from about 5:1 to about 1:5.
12. The solution of claim 3 , wherein the reaction temperature is from about 70° C. to about 90° C.
13. The solution of claim 3 , wherein the reaction time is from about 1 hour to about 40 hours.