Forensic engineering of advanced polymeric materials - Part II: The effect of the solvent-free non-woven fabrics formation method on the release rate of lactic and glycolic acids from the tin-free poly(lactide-co-glycolide) nonwovens

We report the forensic engineering study on the non-woven fabrics made from poly(lactide-co-glycolide), PLGA, with low toxicity. The comprehensive degradation investigations were conducted under abiotic conditions. The extent of degradation was monitored by weight loss, composition and molar mass changes of the copolymer and by macro- and microscopic observations of the sample surfaces. The structure of the degradation products was evaluated at the molecular level by electrospray ionization mass spectrometry and high-performance liquid chromatography analysis. The degradation process takes place predominantly by the bulk erosion mechanism and rate of release of lactic and glycolic acids from the non-woven fabrics is dependent on their formation method. Described solvent-free formation method of nonwovens from the tin-free PLGA results in biomaterials with higher biocompatibility, what is particularly important for their applications. Moreover, the continuous release of lactic and glycolic acids from the PLGA biomaterials studied allows their gradual removal via biochemical processes and prevents local acidification of the body.