Abstract: In this invention, a process of thermal degradation of biodegradable bacterial polyesters poly(hydroxyalkanoate)s (PHAs) to lower molecular weight PHAs in controllable manner has been developed. The process involves using at least one additional component to ‘dilute’ the PHAs in the thermal degradation process, so that the process can be controlled in the senses of better heat transfer, better stirring, easier working up after the reaction. The relationship of processing time and the molecular weights of the products at a certain temperature was obtained so that it is possible to obtain the desired molecular weight products in the real production under the guidance of the relationship.

Abstract: In this invention, a process of thermal degradation of biodegradable bacterial polyesters poly(hydroxyalkanoate)s (PHAs) to lower molecular weight PHAs in controllable manner has been developed. The process involves using at least one additional component to ‘dilute’ the PHAs in the thermal degradation process, so that the process can be controlled in the senses of better heat transfer, better stirring, easier working up after the reaction. The relationship of processing time and the molecular weights of the products at a certain temperature was obtained so that it is possible to obtain the desired molecular weight products in the real production under the guidance of the relationship.

Abstract: The thermal degradation of the biodegradable bacterial polyesters poly(3-hydroxybutyrate), PHB, and poly(3-hydroxybutyrate-co-3-hydroxyvalerate), PHB/V produces a macromer, especially a 1000-6000 g/mol macromolecule, which contains an unsaturated end group as well as a carboxylic acid end group. The macromers may be polymerized to produce homopolymers and copolymers for different applications in which amphiphilic and biocompatible properties are required, for example, drug delivery systems.

Abstract: The thermal degradation of the biodegradable bacterial polyesters poly(3-hydroxybutyrate), PHB, and poly(3-hydroxybutyrate-co-3-hydroxyvalerate), PHB/V produces a macromer, especially a 1000-6000 g/mol macromolecule, which contains an unsaturated end group as well as a carboxylic acid end group. The macromers may be polymerized to produce homopolymers and copolymers for different applications in which amphiphilic and biocompatible properties are required, for example, drug delivery systems.