A. P. BONARTSEV, A. P. BOSKHOMODGIEV, A. L. IORDANSKII, G. A. BONARTSEVA, A. V. REBROV, T. K. MAKHINA, V. L. MYSHKINA, S. A. YAKOVLEV, E. A. FILATOVA, E. A. IVANOV, D. V. BAGROV, G. E. ZAIKOV, and M. I. ARTSIS

5.1 Introduction .................................................................................... 58 5.2 Experimental Part ........................................................................... 59 5.3 Results and Discussion .................................................................. 62 5.4 Conclusion ..................................................................................... 71 Keywords ................................................................................................ 72 References ............................................................................................... 73

5.1 INTRODUCTION

This chapter is designed to be an informative source for biodegradable poly(3-hydroxybutyrate) and its derivatives’ research. We focuses on hydrolytic degradation kinetics at 37 °C and 70 °C in phosphate buffer to compare PLA and PHB kinetic profiles. Besides, we reveal the kinetic behavior for copolymer PHBV (20% of 3-hydroxyvalerate) and the blend PHB-PLA. The intensity of biopolymer hydrolysis characterized by total weight lost and the viscosity-averaged molecular weight (MW) decrement. The degradation is enhanced in the series PHBV < PHB < PHBPLA blend < PLA. Characterization of PHB and PHBV includes MW and crystallinity evolution (X-ray diffraction) as well as AFM analysis of PHB film surfaces before and after aggressive medium exposition. The important impact of MW on the biopolymer hydrolysis is shown.