Patent ID: 8361495

Claim:
A biodegradable cationic block copolymer, comprising: a hydrophilic block comprising first repeat units derived from a first cyclic carbonyl monomer by ring-opening polymerization, wherein more than 0% of the first repeat units comprise a side chain moiety comprising a quaternary amine group; a hydrophobic block comprising second repeat units derived from a second cyclic carbonyl monomer by ring-opening polymerization; an optional endcap group; and a chain fragment derived from a dinucleophilic initiator of the general formula (10): wherein each X′ and each W′ is independently a single bond or a divalent radical selected from the group consisting of —(CR′ 2 ) c —, —O—, —S—, —NR′—, and —NR′(CR′ 2 ) c —; each c is independently an integer from 1 to 5; R′ is a monovalent radical selected from the group consisting of hydrogen, alkyl groups comprising 1 to 30 carbons, and aryl groups comprising 6 to 30 carbons; each Y′ is independently a single bond or a divalent radical selected from the group consisting of —CO— (carbonyl), —NR′CO— (aminocarbonyl), —OCO— (oxycarbonyl) and, —SCO— (thiocarbonyl); each T′ is a monovalent nucleophile independently selected from the group consisting of —OH, —SH, —NH 2 , and —NR d H, wherein R d is a monovalent radical selected from the group consisting of hydrogen, alkyl groups comprising 1 to 30 carbons, and aryl groups comprising 6 to 30 carbons; each Z′ is a monovalent radical independently selected from the group consisting of halides, alkyl groups comprising 1 to 20 carbons, alkoxy groups comprising 1 to 20 carbons, and aryl groups comprising 6 to 20 carbons; each b is an integer independently from 1 to 20; and each d is independently 0 or an integer from 1 to 4; wherein the cationic block copolymer biodegrades 60% within 180 days in accordance with ASTM D6400.