title: Surface bio-modification of poly(hydroxybutyrate-co-hydroxyhexanoate) and its aging effect.
abstract: In this work, poly(hydroxybutyrate-co-hydroxyhexanoate) (PHBHHx) film was fabricated by a solution-casting method and subsequently was modified by NaOH treatment to improve the surface hydrophilic property. Surface properties including hydrophilicity, surface appearance and functional groups were characterized by water contact angle measurement, scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The results showed the hydrophilicity of PHBHHx film was obviously improved by the NaOH treatment due to the topography changes promoted by the NaOH-etching and the introduction of polar groups included hydroxyl and carboxyl on the topmost surface layers. However, the modified film exhibited an aging effect: the hydrophilicity decreases with time elapsed during storage. It was found that the aging rate was strongly dependent on the crystallinity of the film and the storage environment. The sample with high-crystallinity lost hydrophilic property slower than that with low-crystallinity. Hydrophilic and low-temperature environment also prevented the modified PHBHHx from fast losing of the hydrophilicity.
authors: School of Materials Sciences and Engineering, Harbin Institute of Technology, Harbin 150001, China. fengshen0513@gmail.com
authors: Feng
authors: F
authors: Shen
authors: Erlin
authors: E
authors: Zhang
authors: Zunjie
authors: Z
authors: Wei
mesh_terms: D020155:3-Hydroxybutyric Acid / Q000737:chemistry*; D001672:Biocompatible Materials / Q000737:chemistry*; D002208:Caproates / Q000737:chemistry*; D003460:Crystallization; D008855:Microscopy, Electron, Scanning; D012972:Sodium Hydroxide / Q000737:chemistry; D013057:Spectrum Analysis; D013499:Surface Properties; D013997:Time Factors; D014867:Water / Q000737:chemistry; D000094122:Polyhydroxybutyrates
chemical_list: D020155:3-Hydroxybutyric Acid; D001672:Biocompatible Materials; D002208:Caproates; D012972:Sodium Hydroxide; D014867:Water; C115940:poly(3-hydroxybutyrate-co-3-hydroxyhexanoate); D000094122:Polyhydroxybutyrates