SUMMARY: Poly(3-hydroxyalkanoate)-g-poly(ethylene glycol) crosslinked graft copolymers are described. Poly(3-hydroxyalkanoate)s containing double bonds in the side chain (PHA-DB) were obtained by co-feeding Pseudomonas oleovorans with a mixture of nonanoic acid and anchovy (hamci) oily acid (in weight ratios of 50/50 and 70/30). PHA-DB was thermally grafted with a polyazoester synthesized by the reaction of poly(ethylene glycol) with MW of 400 (PEG-400) and 4,49-azobis(4-cyanopentanoyl chloride). Sol-gel analysis and spectrometric and thermal characterization of the networks are reported.

Thermal inactivation kinetics of native and glutaraldehyde cross‐linked forms of penicillin G acylase obtained from a mutant derivative of Escherichia coli ATCC 11105 were studied. Apparent activation energies for thermal inactivation of both native and cross‐linked forms of enzyme were calculated to be [57‐71 ± 8.46] and [67.11 ± 13.83] kcal mol−1 respectively. This slight increase in activation energy‐suggested that glutaraldehyde cross‐linking did not markedly protect against thermal inactivation. Cross‐linked enzyme did, however, have a significantly improved half‐life at temperatures between 40°C and 50°C.

Poly(3-hydroxyalkanoate)-g-poly(ethylene glycol) crosslinked graft copolymers are described. Poly(3-hydroxyalkanoate)s containing double bonds in the side chain (PHA-DB) were obtained by co-feeding Pseudomonas oleovorans with a mixture of nonanoic acid and anchovy (hamci) oily acid (in weight ratios of 50/50 and 70/30). PHA-DB was thermally grafted with a polyazoester synthesized by the reaction of poly(ethylene glycol) with MW of 400 (PEG-400) and 4,49-azobis(4-cyanopentanoyl chloride). Sol-gel analysis and spectrometric and thermal characterization of the networks are reported.