Blends of bacterial and synthetic poly(β-hydroxybutyrate): effect of tacticity on melting behaviour

Pearce, R.; Jesudason, J. J.; Orts, William J.; Marchessault, R. H.; Bloembergen, Steven

doi:10.1016/0032-3861(92)90428-y

Cited by 61 publications

(32 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The elastic modulus, i.e., the stiffness decreased with increasing concentration of at-PHB, as was already found by tensile testing. All findings about the mechanical behavior of this study are in agreement with earlier results of Pearce et al [28] and Abe et al [29]. The modulus decreased with increasing content of at-PHB in the region of the glass transition due to the onset of increased mobility of macromolecules.…”

Section: Mechanical and Thermal Propertiessupporting

confidence: 94%

“…Our data differ from the findings in Ref. [28] where no change of the melting temperatures was observed. The melting temperature of a polymer crystal is controlled (a) by the crystal structure, i.e., the specific interactions between molecules within the crystal, and (b) by the crystal morphology, i.e., the shape, size and perfection of the crystal, as well as the surface properties.…”

Section: Mechanical and Thermal Propertiescontrasting

confidence: 86%

See 1 more Smart Citation

In vitro and in vivo studies on blends of isotactic and atactic poly (3-hydroxybutyrate) for development of a dura substitute material

et al. 2006

View full text Add to dashboard Cite

Section: Mechanical and Thermal Propertiessupporting

confidence: 94%

Section: Mechanical and Thermal Propertiescontrasting

confidence: 86%

In vitro and in vivo studies on blends of isotactic and atactic poly (3-hydroxybutyrate) for development of a dura substitute material

et al. 2006

View full text Add to dashboard Cite

“…Pearce et al [339] prepared blends of bacterial and partially isotactic P(3HB); both solvent cast films and rapidly co-precipitated powders were used. Pearce et al [339] prepared blends of bacterial and partially isotactic P(3HB); both solvent cast films and rapidly co-precipitated powders were used.…”

Section: Article In Pressmentioning

confidence: 99%

The chemomechanical properties of microbial polyhydroxyalkanoates

Laycock

Halley

Pratt

et al. 2014

Progress in Polymer Science

214

204

View full text Add to dashboard Cite

Available online xxx Keywords: Biopolymer Polyhydroxyalkanoates Microbial polyesters Poly((R)-3-hydroxybutyrate) Poly((R)-3-hydroxybutyrate-co-3hydroxyvalerate) Mechanical properties a b s t r a c tMicrobially produced polyhydroxyalkanoates (PHAs) are fully biodegradable biopolyesters that have attracted much attention recently as alternative polymeric materials that can be produced from biorenewable and biowaste resources. The properties of these biological polymers are affected by the same fundamental principles as those of fossil-fuel derived polyolefins, with a broad range of compositions available based on the incorporation of different monomers into the PHA polymer structure, and with this broad range tailoring subsequent properties. This review comprehensively covers current understanding with respect to PHA biosynthesis and crystallinity, and the effect of composition, microstructure and supramacromolecular structures on chemomechanical properties. While polymer composition and microstructure are shown to affect these properties, the review also finds that a key driver for determining polymer performance properties is compositional distribution. From this review it follows that PHA-PHA blend compositions are industrially important, and the performance properties of such blends are discussed. A particular need is identified for further research into the effect of chemical compositional distribution on macromolecular structure and end-use properties, advanced modeling of the PHA accumulation process and chain growth kinetics for better process control.

show abstract

“…Pearce et al made similar observations for blends of isotactic and atactic PHB. [35] It means the crystalline structures are coined dominantly by the component in excess. This observation agrees with Equation (4) and (5) which favor co-crystallization.…”

Section: Non-isothermal Crystallizationmentioning

confidence: 99%

Crystallization and Melting Behavior of Poly(3‐hydroxybutyrate)‐Based Blends

Chan

Kummerlöwe²,

Kammer

2004

Macro Chemistry & Physics

View full text Add to dashboard Cite

Summary: Blends of high molecular weight poly(R‐3‐hydroxybutyrate) (PHB) ($\overline M _{\rm w}$ = 352 000 g · mol−1), comprising of either low molecular weight poly(R‐3‐hydroxybutyrate) (D‐PHB) ($\overline M _{\rm w}$ = 3 900 g · mol−1) or poly[(R‐3‐hydroxybutyrate)‐co‐(R‐3‐hydroxyvalerate)] (PHBV) ($\overline M _{\rm w}$ = 238 000 g · mol−1) with 12 mol‐% hydroxyvalerate (HV) content as a second constituent, were investigated along with the thermal properties and morphologies. After isothermal crystallization, a lowering of the melting temperature of PHB can be observed with increasing content of the second component in the blends. This behavior points towards miscibility of the constituents both in the liquid and the solid state. Crystallization kinetics was studied under isothermal and non‐isothermal conditions. The overall kinetics of isothermal crystallization was analyzed in terms of the Avrami equation. Only one crystallization peak is observed in all cases for the PHB/D‐PHB and PHB/PHBV blends under the conditions studied. This demonstrates co‐crystallization of the constituents. The addition of D‐PHB or PHBV to PHB reduces the rate of crystallization of the blends compared to that of neat PHB. The corresponding activation energies of crystallization also decrease with an increasing concentration of the second constituent. Non‐isothermal crystallization, carried out with different cooling rates held constant, is discussed in terms of a quasi‐isothermal approach. The corresponding rate constants as functions of reciprocal undercooling show Arrhenius‐like behavior in a certain range of temperatures. At sufficiently high undercooling, the rate constants of crystallization for the isothermal process exceed those reflecting non‐isothermal conditions, whereas in the limit of low undercoolings, the rate constants become similar. Ring‐banded morphologies are observed when PHB is in excess. When the respective second component is the major component, fibrous textures of the spherulites develop.Polarized micrograph of PHB/PHBV 90/10.magnified imagePolarized micrograph of PHB/PHBV 90/10.

show abstract

Blends of bacterial and synthetic poly(β-hydroxybutyrate): effect of tacticity on melting behaviour

Cited by 61 publications

References 14 publications

In vitro and in vivo studies on blends of isotactic and atactic poly (3-hydroxybutyrate) for development of a dura substitute material

In vitro and in vivo studies on blends of isotactic and atactic poly (3-hydroxybutyrate) for development of a dura substitute material

The chemomechanical properties of microbial polyhydroxyalkanoates

Crystallization and Melting Behavior of Poly(3‐hydroxybutyrate)‐Based Blends

Contact Info

Product

Resources

About