Alpha, omega-allyl terminated linear poly(methacrylic acid) macromonomers for end-linked hydrogels and method of preparation

摘要

Disclosed is a method for making α,ω-allyl terminated macromonomers comprising a plurality of units of an α,β-unsaturated carboxylic acid. The method comprises forming a first mixture containing an ester of an α,β-unsaturated carboxylic acid, a radical initiator comprising an allyl group and a halogen, and a catalyst comprising a transition metal complex. The ester of the α,β-unsaturated carboxylic acid is an ester capable of reacting with a mixture comprising trifluoroacetic acid (TFA) to form the α,β-unsaturated carboxylic acid. The mixture is stirred to form a second mixture containing an α-allyl, ω-halogen-terminated macromonomer comprising a plurality of units of the ester of the α,β-unsaturated carboxylic acid. A third mixture comprising a compound containing at least one transferable allyl group is then added to the second mixture to form a fourth mixture containing a first α,ω-allyl terminated macromonomer comprising a plurality of units of the ester of the α,β-unsaturated carboxylic acid. The first α,ω-allyl terminated macromonomer is separated from the fourth mixture and is mixed with a mixture containing TFA to form a fifth mixture containing the α,ω-allyl terminated macromonomer comprising a plurality of units of the α,β-unsaturated carboxylic acid. The α,ω-allyl terminated macromonomer comprising a plurality of units of the α,β-unsaturated carboxylic acid is then separated from the fifth mixture. Also enclosed is a related method for making end-linked hydrogels comprising a plurality of units of an α,β-unsaturated carboxylic acid. The method comprises forming a first mixture containing an α,ω-allyl terminated macromonomer comprising a plurality of units of the α,β-unsaturated carboxylic acid and a radical initiator. The first mixture is treated with UV-radiation, visible light, or heat to form a second mixture comprising an end-linked hydrogel comprising a plurality of units of the α,β-unsaturated carboxylic acid.