Photo-Crosslinked Elastomeric Bimodal Poly(trimethylene carbonate) Networks

Using methacrylated poly(trimethylene carbonate) oligomers unimodal (prepared from one macromer) and bimodal (prepared from two macromers with different molecular weights) photo-crosslinked networks and structures are prepared by stereolithography. The obtained biodegradable networks are flexible and elastic. Compared to the corresponding unimodal networks, the tensile properties of bimodal poly(trimethylene carbonate) (PTMC) network films are significantly enhanced. Resilient materials with increased toughness and suture retention strengths are obtained. The mechanical properties of the bimodal networks compare favorably with those of unimodal networks prepared previously from PTMC macromers with much higher molecular weights. Tough porous PTMC structures with designed diamond pore network architectures can also be readily prepared by stereolithography. Upon swelling of these PTMC structures in a solvent, the pore sizes and pore size distribution increases while the porosity decreases.