In vitro degradation behavior of functionalized cellulosic fibers reinforced PLA composite

摘要

Cellulosic fibers are renewable and also light in weight which make them a good candidate as reinforcing elements in bio-composites. Having hydrophilic nature resulted by presence of hydroxyl groups in the structure of these fibers restricts their application in the polymeric matrices because of poor interfacial adhesion, and the low dispersion within the matrix. To resolve these problems this study tried firstly to functionalize the flax fibers with selective oxidation. This improves the adhesion of subsequent amphiphilic TiO2 thin films created by Sol-Gel technique. The PLA matrices were reinforced by using non/functionalized, TiO2/ non -coated flax fibers. The composites were conditioned in simulated body solution at 37°C to induce the degradation. The behaviour of the PLA/glass composite has been analysed during its degradation in simulated physiological condition. Physical and mechanical properties of the composites and the interfacial strength between the matrix and the fibers were characterized quantitatively and qualitatively. The results showed better interfacial properties within functionalized flax fiber reinforced composites comparing to non-functionalized ones. Functionalized TiO2 coated flax reinforced composites showed better mechanical properties within the first 15 weeks of conditioning comparing to the control samples.