BC Thermoplastic and Thermosetting Nanocomposites

PLA is a biodegradable aliphatic polyester produced from D- and L-lactic acid, commonly obtained from fermentation of starch enriched products like sugar beet, corn and wheat [154]. Over the past few years, a considerable number of studies dealing with the reinforcement of PLA with BC have been reported in literature. One of the 

In a more fundamental vein, Zhang et al. [157] studied the confined crystallization behavior of PLA/acetylated BC nanocomposites prepared by compression molding. The results indicated that acetylated BC favored the crystallization of PLA at higher temperatures. In a similar mode, Quero et al. [158] investigated the micromechanical properties of laminated BC/PLA nanocomposites by Raman spectroscopy as a mean to understand the fundamental stress-transfer processes in these nanocomposites and as a tool to select appropriate processing and volume fraction of the fibers. Results showed that Young s modulus and stress at failure of PLA films were foimd to increase by 100 and 315%, respectively, for 18% volume fraction of BC and BC membranes cultured for 3 days exhibited enhanced interaction with PLA because of their higher total surface area. 

The research group of Bismarck has been also exploring the surface functionalization of BC as a road to create PLA nanocomposites with upgraded properties. The functionalization with various organic acids rendered BC nanofibers hydrophobic [161, 162] and resulted in better interfacial adhesion between PLA and BC [163]. In 

Polyhydroxyalkanoates (PHAs) are a family of intracellular biopolyesters synthesized by bacteria as intracellular carbon and energy storage granules. Poly(3-hydroxybutyrate) 

BC-reinforced xmsaturated polyester resin nanocomposites were prepared using vinyl triethoxysilane-modified BC fibers by the resin transfer molding (RTM) methodology [180]. The X-Ray photoelectron spectroscopy (XPS) analysis revealed that chemical bonding was formed between the matrix and the modified BC fibers which resulted in composites with improved mechanical properties. 

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