Patent ID: 8309623

Claim:
A biodegradable copolymer, having a general formula: A—B; wherein A is a hydrophilic segment, having a general formula: R 1 is C 1-8 alkyl; R 2 is ethyl, C 1-8 alkyl ethyl, C 1-8 alkoxyl ethyl, or combinations thereof; and n is an integer of 5-20; and wherein B is a hydrophobic segment, having a general formula: R 3 is hydrogen or methyl; R 4 is a linear saturated or unsaturated C 2 -C 5 alkanediyl group comprising one or more hetero atoms including O, S or N, branched or cyclic, saturated or unsaturated C 3 -C 5 alkanediyl group comprising one or more hetero atoms including O, S or N; J is C═O, C═S, C—CHO, C═NH, or C═NR 5 , wherein R 5 is C 1 -C 3 alkyl group; K is S, C—CHO, NH, or NR 6 , wherein R 6 is C 1 -C 3 alkyl group; x is an integer of 5-20; y is an integer of 5-20; and x is greater than or equal to y.