title: Characterization, biodegradability and blood compatibility of poly[(R)-3-hydroxybutyrate] based poly(ester-urethane)s.
abstract: Poly(ester-urethane)s (PUs) were synthesized using hexamethylene diisocyanate (HDI) or toluene diisocyanate (TDI) to join short chains (M(n) = 2000) of poly(R-3-hydroxybutyrate) (PHB) diols and poly(epsilon-caprolactone) (PCL) diols with different feed ratios under different reaction conditions. The multiblock copolymers were characterized by nuclear magnetic resonance spectrometer (NMR), gel permeation chromatography (GPC), differential scanning calorimetry (DSC), thermogravimetric analyses (TGA), X-ray diffraction (XRD), and scanning electron microscope (SEM). XRD spectra and second DSC heat thermograms of the multiblock copolymers revealed that the crystallization of both PHB and PCL segments was mutually restricted, and, especially, the PCL segment limited the cold crystallization of the PHB segment. The SEM of platelet adhesion experiments showed that the hemocompatibility was affected to some extent by the chain flexibility of the polymers. Hydrolysis studies demonstrated that the hydrolytic degradation of PUs was generated from the scission of their ester bonds or/and urethane bonds. Simultaneously, the rate of ester bond scission was determined to some extent by the crystallization degree, which was further affected by the configuration of polymer chains. These highly elastic multiblock copolymers combining hemocompatibility and biodegradability may be developed into blood contact implant materials for biomedical applications.
authors.affiliation: Multidisciplinary Research Center, Shantou University, Shantou, Guangdong 515063, China.
authors.forename: Qiaoyan
authors.initials: Q
authors.lastname: Liu
authors.forename: Shaoting
authors.initials: S
authors.lastname: Cheng
authors.forename: Zibiao
authors.initials: Z
authors.lastname: Li
authors.forename: Kaitian
authors.initials: K
authors.lastname: Xu
authors.forename: Guo-Qiang
authors.initials: GQ
authors.lastname: Chen
mesh_terms: D001672:Biocompatible Materials / Q000138:chemical synthesis* / Q000737:chemistry; D001773:Blood Cells / Q000187:drug effects*; D003460:Crystallization; D006801:Humans; D006868:Hydrolysis; D006885:Hydroxybutyrates / Q000737:chemistry; D007700:Kinetics; D010973:Platelet Adhesiveness; D011091:Polyesters / Q000737:chemistry* / Q000494:pharmacology; D011140:Polyurethanes / Q000737:chemistry* / Q000494:pharmacology; D000091402:Prohibitins
chemical_list: D001672:Biocompatible Materials; D006885:Hydroxybutyrates; C000717328:PHB protein, human; D011091:Polyesters; D011140:Polyurethanes; D000091402:Prohibitins; C081821:microthane foam