Multiple melting behavior of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) investigated by differential scanning calorimetry and infrared spectroscopy

Hu, Yun; Zhang, Jianming; Sato, Harumi; Noda, Isao; Ozaki, Yukihiro

doi:10.1016/j.polymer.2007.06.016

Cited by 56 publications

(38 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These DSC results imply that the melt of PHBHHx is likely to be the melt‐recrystallization remelting mechanism. This suggestion is in agreement with the results reported by Hu et al16 Therefore, it is concluded that the endotherm P 2 is attributed to the melt of primary crystals developed during isothermal crystallization, and the peak P 3 is ascribed to the melting of crystals formed in the recrystallization process upon heating.…”

Section: Resultssupporting

confidence: 93%

“…All these physical properties can be well regulated by changing the content and distribution of comonomer units. In recent years, the biosynthesis,6–10 biodegradation,11–14 crystallization behavior,15–18 physical properties,19–23 and biomedical applications24–28 of PHBHHx have been extensively studied from both academic and industrial viewpoints.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Uracil as Nucleating Agent for Bacterial Poly[(3‐Hydroxybutyrate)‐co‐(3‐hydroxyhexanoate)] Copolymers

Pan

Liang

Nakamura

et al. 2009

Macromolecular Bioscience

View full text Add to dashboard Cite

In this study, uracil has been introduced as the nucleating agent (NA) for bacterially synthesized poly[(3-hydroxybutyrate)-co-(3-hydroxyhexanoate)] (PHBHHx) copolymers with HHx content of 5, 10, 18 mol-%, and poly(3-hydroxybutyrate) (PHB) homopolymer for the first time. Its effect was compared with the conventional NA of PHB, that is, boron nitride (BN), and two other naturally occurring pyrimidine derivatives, i.e., thymine and cytosine. The effects of uracil on the crystallization kinetics, melting behavior, spherulite morphology, and crystalline structure of PHBHHx and PHB were investigated by differential scanning calorimetry (DSC), polarized optical microscopy (POM), and wide-angle X-ray diffraction (WAXD). Uracil and BN exhibit the comparable nucleation efficiency on the crystallization of PHB, whereas uracil shows much more effective nucleation ability than BN for PHBHHx copolymers. With incorporation of 1 wt.-% uracil, PHBHHx with 0-10 mol-% HHx units can finish crystallization upon cooling at 10 degrees C x min(-1). The crystallization half-times (t(1/2)) of all the PHB and PHBHHx samples decrease significantly with presence of uracil. The crystallization rate of polymers further enhances with increase in uracil concentration. With addition of 1 wt.-% uracil, the t(1/2) value of PHBHHx with 10 mol-% HHx units melt-crystallizing at 80 degrees C decreases to approximately 4.0% of the neat polymer, and the nucleation density increases by 3-4 orders of magnitude. The incorporation of uracil has no discernable effect on the crystalline structure of PHBHHx, as evidenced by WAXD results. It was proposed that the nucleation mechanism of the uracil/PHBHHx (or PHB) system might be the epitaxial nucleation.

show abstract

Section: Resultssupporting

confidence: 93%

Section: Introductionmentioning

confidence: 99%

Uracil as Nucleating Agent for Bacterial Poly[(3‐Hydroxybutyrate)‐co‐(3‐hydroxyhexanoate)] Copolymers

Pan

Liang

Nakamura

et al. 2009

Macromolecular Bioscience

View full text Add to dashboard Cite

show abstract

“…As shown in panel b of Figures 1 and 2, NA does not influence the melting behavior of PHB, PHBV, and PHBH. In contrast to the single melting peak of PHB, PHBV and PHBH show two melting peaks upon heating, ascribing to the melt‐recrystallization mechanism 29…”

Section: Resultsmentioning

confidence: 87%

Crystallization kinetics of bacterial poly(3‐hydroxylbutyrate) copolyesters with cyanuric acid as a nucleating agent

Pan

Shan

Bao

et al. 2012

J of Applied Polymer Sci

View full text Add to dashboard Cite

Effects of cyanuric acid (CA) on nonisothermal and isothermal crystallization, melting behavior, and spherulitic morphology of bacterial copolyesters of poly(3‐hydroxybutyrate), i.e., poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHBV) and poly(3‐hydroxybutyrate‐co‐3‐hydroxyhexanoate) (PHBH), have been investigated. CA has excellent acceleration effectiveness on the melt crystallization of bacterial PHB, PHBV, and PHBH, better than the nucleating agents reported in the literatures, such as boron nitride, uracil, and orotic acid. PHBV and PHBH do not crystallize upon cooling from the melt at 10°C/min, while they are able to complete crystallization under the same conditions with an addition of 1% CA, with a presence of sharp crystallization exotherm at 75–95°C. Isothermal crystallization kinetics of neat and CA‐containing PHBV and PHBH were analyzed by Avrami model. Crystallization half‐times (t1/2) of PHBV and PHBH decrease dramatically with an addition of CA. The melting behavior of isothermally melt‐crystallized PHBV and PHBH is almost not influenced by CA. Spherulitic numbers of PHBV and PHBH increase and the spherulite sizes reduce with an incorporation of CA. Nucleation densities of PHBV and PHBH increase by 3–4 orders of magnitude with a presence of 1% CA. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

show abstract

“…The melting peak area at T a was small and its contribution to the overall degree of crystallinity was insignificant. The melting temperature T m1 is related to the melting of crystals formed originally while the melting temperature T m2 is associated with the melting of crystals that were recrystallized during the heating process .…”

Section: Resultsmentioning

confidence: 99%

Effects of glass fibers on mechanical and thermal properties of poly(3‐hydroxybutyrate‐co‐3‐hydroxyhexanoate)

Arifin

Kuboki

2016

Polymer Composites

View full text Add to dashboard Cite

This study investigates the effects of glass fiber on the mechanical and thermal properties of bacterial polyester, poly(3-hydroxybutyrate-co23-hydroxyhexanoate) (PHBH). PHBH composites were prepared by melt-compounding and injection molding, using PHBH with 3-hydroxyhexanoate (3HH) molar fractions of 5.6 and 11.1%, and short glass fiber content varying from 0 to 23 volume percent. Tensile test results suggested that the glass fiber addition significantly increased Young's modulus and strength of PHBH. The Halpin-Tsai and Tsai-Pagano equations were used to predict Young's modulus of PHBH composites while the modified KellyTyson model with the Bowyer-Bader method were used for strength prediction. These predictions gave reasonable estimates for the mechanical properties of PHBH composites. Differential scanning calorimetry results suggested that glass fiber addition had little effect on the degree of crystallinity of PHBH, as well as on the crystallization half-time of PHBH containing 5.6 mol% 3HH. POLYM. COMPOS., 00:000-000, 2016.

show abstract

Multiple melting behavior of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) investigated by differential scanning calorimetry and infrared spectroscopy

Cited by 56 publications

References 46 publications

Uracil as Nucleating Agent for Bacterial Poly[(3‐Hydroxybutyrate)‐co‐(3‐hydroxyhexanoate)] Copolymers

Uracil as Nucleating Agent for Bacterial Poly[(3‐Hydroxybutyrate)‐co‐(3‐hydroxyhexanoate)] Copolymers

Crystallization kinetics of bacterial poly(3‐hydroxylbutyrate) copolyesters with cyanuric acid as a nucleating agent

Effects of glass fibers on mechanical and thermal properties of poly(3‐hydroxybutyrate‐co‐3‐hydroxyhexanoate)

Contact Info

Product

Resources

About