Miscibility and Crystallization Behavior of Poly(3-hydroxy butyrate-co-3-hydroxy hexanoate) and Methoxy poly(ethylene glycol) Blends.

摘要

Poly hydroxyl alkanoates, (PHAs) are biodegradable aliphatic polyesters synthesized by bacteria1). Recently, Poly(3-hydroxy butyrate- co-3-hydroxyhexanoate) (PHB-HHx), composed of 3-hydroxy butyrate and a little amount of 3-hydroxyhexanoate comonomer unit, has been introduced to the PHA family and also has been receiving much attention as biodegradable polymer field2). PHB-HHx has the characteristics of conventional semi-crystalline polymers such as polyethylene and polypropylene3) and possesses improved thermo-plasticity and mechanical properties than those of pre-existing other PHAs. In addition, this co-polyester has excellent compatibility with other biodegradable polymers. However, PHB-HHx has been limited to practical application because of some disadvantages, such as hydrophobicity, low crystallization rate and high cost. To overcome these limitations, much effort has been made to blend the PHB-HHx and other polymers. Methoxy Poly (ethylene glycol), (MPEG), the one of PEG family, has been extensively investigated for biomaterial field because of its biocompatibility, biodegradability and hydrophilicity. In other hand, the crystallization and morphological behavior corresponding to blend miscibility have a major effect on the conventional melt process such as injection molding. In this research, the miscibility and crystallization behavior of PHB-HHx/MPEG blend were investigated. The addition of MPEG is expected to make the useful candidate that improves defects of PHB-HHx.