COPOLIMEROS POLYETHYLENGLYCOL POLYETHYLENE POLYETHYLENE POLISHESTER WITH LOW MOLECULAR WEIGHT THAT HAVE REVERSE THERMAL GELIFICATION PROPERTIES.

摘要

A composition comprising a biodegradable tribloque polymer of type ABA or BAB having reverse thermal gelation properties, characterized in that said tribloque comprises: i) approximately 51% to 83% by weight of a block of hydrophobic, biodegradable polymer A comprising a biodegradable polyester, which is synthesized from monomers selected from the group consisting of epsilon-caprolactone, epsilon-hydroxyhexonoic acid, gamma-butyrolactone, gamma-hydroxybutyric acid, delta-valerolactone, delta-hydroxyvaleric acid, hydroxybutyric acids, malic acid and copolymers thereof; and ii) about 17% to 49% by weight of a biodegradable hydrophilic polymer B block, comprising a polyethylene glycol (PEG); wherein said triblock copolymer has an average molecular weight between about 2,000 to 4,990 and in which the concentration of said block copolymer is between 3% and 50% by weight and said composition exists as a clear aqueous solution between about 5 ° C and 25 ° C but forms a gel when the temperature increases to approximately body temperature (typically 37 ° C for humans).