Effect of Poly(ethylene glycol) on the Ultrastructure and Physicochemical Properties of the Poly(3‐hydroxybutyrate)

Abstract

Chemical conjugation or blending with poly(ethylene glycols) (PEGs) are established procedures to facilitate solubilisation of hydrophobic compounds. The techniques of bioPEGylation and blending with PEG were applied to poly(3‐hydroxybutyrate). In this paper we have examined the properties of copolymer of poly(3‐hydroxybutyrate‐co‐poly(ethylene glycol)) (PHB‐PEG) and composite material polyhydroxybutyrate with poly(ethylene glycol) (PHB + PEG) compared to homopolymer of poly(3‐hydroxybutyrate) (PHB). It was found that copolymer has significally different mechanical and thermophysical properties with respect to pure PHB: an increased crystallinity but a decreased Young's modulus and elongation at break. Moreover, the creation of the composite, and a copolymer of PHB with PEG results in a change in surface morphology of ultrathin films.

Biodegradation of Poly(3-Hydroxybutyrate) and Poly(3-Hydroxybutyrate-Co-3-Hydroxy-4-Methylvalerate) Films by Porcine Pancreatic Lipase

“…In the animal organism PHA degradation occurs as a result of a combination of hydrolytic and enzymatic degradation. It leads changes in weight of the samples and its physical and chemical properties [1][2][3][31][32][33][34][35][36]. Analysis of the degradation kinetic curves (Fig.…”

“…The loss of polymer weight due to degradation was determined gravimetrically using a AL-64 balance (Acculab, USA). Every three days the solutions were replaced by the fresh ones [31][32][33][34][35][36]. To avoid bacterial contribution to the degradation of polymers, sodium azide (NaN 3 ) at a concentration of 2 g/l was added to the buffer solution, and the buffer solution was changed twice a week [37].…”

“…Nanoindentation of PHAs Films. Study of the mechanical properties was carried out by method of instrumented nanoindentation according to the requirements of ISO 14577 using scanning nanohardness tester NanoScan-4D (FSBI TISNCM, Troitsk, Moscow, Russia) [34][35][36]. Nanoindentation was performed on the smooth side of the film.…”

“…Molecular weights (Mw) of PHB and PHB-4MV were determined by viscosimetry. The viscosity of the PHB solution in chloroform was measured at 30 °C on a RT RheoTec viscometer (RheoTec Messtechnik GmbH, Germany); the molecular weight was calculated using the Mark-Kuhn-Houwink equation [34][35][36] [η] = 7.…”

Biocomposite Materials Based on Poly(3-hydroxybutyrate) and Chitosan: A Review

“…The crystalline structure of PHB is usually in the form of lamellae. The lamellae thickness varies from 4 to 10 nm depending on the molecular weight, solvent, and crystallization temperature [116,117].…”