Shape Memory Effect of Bacterial Poly[(3-hydroxybutyrate)-co-(3-hydroxyvalerate)]
โ Scribed by Young Baek Kim; Chung Wook Chung; Hyung Woo Kim; Young-Ha Rhee
- Publisher
- John Wiley and Sons
- Year
- 2005
- Tongue
- English
- Weight
- 188 KB
- Volume
- 26
- Category
- Article
- ISSN
- 1022-1336
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โฆ Synopsis
Abstract
Summary: A bacterial poly[(3โhydroxybutyrate)โcoโ(3โhydroxyvalerate)] biosynthesized by Pseudomonas sp. HJโ2 was found to be a shape memory polymer. Permanent shapes were set by annealing at room temperature the samples that had been preโtreated above 95โยฐC in specified shapes. The temporary shapes were set by stretching and holding the elongated samples. Thermal shrinkage began at 45โยฐC and stopped at 75โยฐC to recover to their permanent shapes. Apparently, the orientation induced the formation of hard segments that were responsible for setting the temporary shapes. The shape memory effect of this polymer was explained based on the DSC and XRD results at different phases.
The recovery of a coil shape upon heating a strip of HJโ2 PHB35V, demonstrating the polymers shape memory effect.
magnified imageThe recovery of a coil shape upon heating a strip of HJโ2 PHB35V, demonstrating the polymers shape memory effect.
๐ SIMILAR VOLUMES
Water sorption and diffusion have been investigated in poly(3-hydroxybutyrate) (PHB) and three poly(3-hydroxybutyrate-co-3-hydroxyvalerate) copolymers [P(HB-HV)] by means of a Cahn electromicrobalance. Permeability of these samples have been determined using a gravimetric permeation cell. Two experi
## Abstract The preparation and properties of nanocomposites, consisting of a poly(3โHydroxybutyrateโ__co__โ3โhydroxyvalerate) and an organophilic clay are described. The effect of organophilic clay on the crystallization behavior of (PHBV) was studied. A differential scanning calorimeter (DSC) was
CO 2 sorption and diffusion in poly(3-hydroxybutyrate) and three poly(3hydroxybutyrate-co-3-hydroxyvalerate) copolymers were investigated gravimetrically at temperatures from 25ยฐto 50ยฐC and pressures up to 1 atm. The sorption behavior proved to be linear for all the copolymers studied. An additional