Poly(propylene fumarate) is copolymerized with poly(caprolactone) diol to produce a block copolymer of poly(propylene fumarate) and poly(caprolactone). The biocompatible and bioresorbable block copolymer of poly(propylene fumarate) and poly(caprolactone) is useful in the fabrication of injectable and in-situ hardening scaffolds for tissue and/or skeletal reconstruction. The block copolymer can be crosslinked by redox or photo-initiation, with or without an additional crosslinker. Thus, the copolymer is both self-crosslinkable (without the use of any crosslinkers) and photocrosslinkable (in the presence of photons such as UV light).