A bulk extrusion polymerization process to derive an aliphatic polyester from a suitable ester monomer, preferably .epsilon.-caprolactone. Novel reaction formulations containing less than 100 ppm water and having an acid value less than 0.5 mg KOH/g and preferably less than 0.2 mg KOH/g enable...http://www.google.com.au/patents/US5801224?utm_source=gb-gplus-sharePatent US5801224 - Bulk reactive extrusion polymerization process producing aliphatic ester polymer compositions 
