Provided are novel biocompatible copolymers and compositions comprising the copolymers. The copolymers and degradation products thereof are non-toxic and typically have an LCST between room temperature and 37° C. so that they are liquid at room temperature and gelled at 37° C. which facilitates their use in humans, for example for wound treatment and as a cellular growth matrix or niche. The copolymer comprises numerous ester linkages in its backbone so that the copolymers are erodeable in situ. Degradation products of the polymer are soluble and non-toxic. The copolymer is amine-reactive so that it can conjugate with proteins, such as collagen. Active ingredients, such as drugs, can be incorporated into compositions comprising the copolymer.