Polylactide composite materials with inorganic filler -calcium carbonate which have been modified with epoxidized soybean oil and glycerin have been developed. On the basis of the modular-deformation method of calculation the elastic-plastic properties of the developed polylactide materials and the coefficient of structure are determined. The change of the modulus of deformation, modulus of elasticity, surface hardness, Vicat softening point and thermomechanical characteristics of polylactide composites is revealed.
The most common additive methods of processing polylactide materials are analyzed. Attention is paid to the features of methods of selective laser sintering, stereolithography and modeling by layer surfacing, as well as the advantages and disadvantages of using biodegradable materials, including polylactide. Approaches to the development of composite materials based on polylactide with additives of different nature and their technological and operational characteristics are substantiated.
The technological parameters of the process and the design of the extrusion head for the manufacture of products such as “pipe” of polylactide composite materials by extrusion, its construction elements are calculated. Prototypes of a product made of biodegradable plastic were obtained.
The influence of talc filler, its content, as well as an additional heat treatment and temperature on the regularities of polylactide materials water-absorption has been researched. Based on the obtained data, the water diffusion coefficient in polylactide materials and the activation energy of the diffusion process were determined. It was found that the process of water absorption by the filled and heat-treated materials based on polylactide proceeds slower and requires more activation energy of the process.
The influence of the filler - talc, its content, additional heat treatment and temperature on the physical-mechanical and thermophysical properties of polylactide materials, in particular on the surface hardness, heat resistance according to Vick and thermomechanical characteristics has been studied. The influence of filler and temperature on the resistance of polylactide materials to the action of the aqueous medium is revealed. The diffusion coefficient of water in polylactide materials and the activation energy of the diffusion process were determined.
Technological features of obtaining biodegradable binary blends of polylactide with polyhydroxybutyrate, polycaprolactone, thermoplastic starch, polybutylene adipate-co-terephthalate, polybutylene succinate, polybutylene succinate-co-adipate are considered. The influence of polymer applications on physical-mechanical, thermophysical, technological properties and ability to biodegradation and biocompatibility of the obtained materials is revealed. The main possible directions of using binary biodegradable polylactide blends are considered.
We focused on hydrolytic degradation kinetics at 310 and 343 K in phosphate buffer to compare PLA and PHB kinetic profiles. Besides, we revealed the kinetic behavior for copolymer PHBV (20 % of 3-hydroxyvalerate) and the blend PHB-PLA (1:1). The intensity of biopolymer hydrolysis is characterized by total weight lost and the viscosity-averaged molecular weight (MW) decrement. The degradation is enhanced in the series PHBV < PHB < PHB-PLA blend < PLA.