The influence of the environment on the degradation of polylactides and their composites

Purpose: The aim of this paper was to determine the influence of environment on degradation process of polylactide-based materials assigned for the implementation in medical implants and short-life products. The hydrolytic degradation, the biodegradation and the degradation under in vivo conditions were determined for the polylactide (PLA), the lactide and glycolide copolymer (PGLA) and the composites modified by hydroxyapatite particles, carbon fibres and natural fibres (hemp, jute). Design/methodology/approach: The degradation was analyzed on the basis of the changes occurring in the environment (such as those in pH fluids), the changes of the mass and resistance of the examined materials, as well as the structural infrared analyses. Findings: It was stated that the degradation time depends on the type of the environment with which the material is in contact. In the water environment, the degradation is faster than in the presence of a compost, and in the Ringer fluid, its speed is higher than in the artificial serum SBF. The in vitro observations focus mainly on the chemical interaction between the examined materials and the artificial environment. The degradation speed is dependent, among others, on the viscosity of the applied fluids and thus, their ability of penetration in the polymer’s structure and on the interfacial boundaries. In a living organism, the fundamental role is played by such processes as the protein adsorption, the cellular and tissue reactions, the body fluid flows and the charge exchanges, and thus, the degradation process is significantly faster than that under in vitro conditions. Practical implications: Result of this study can be used to elaborate the manufacturing method of implants with controlled resorption time and degradable short life time products like packages. Originality/value: In this paper effect of hydrolytic degradation, biodegradation and in vivo degradation on polymers’ and composites’ behaviour was shown. Result of this study can be used to prognosis of durability of degradable materials.