Novel Green Composites from Recycled Newspaper Fibers and Poly(hydroxyalkanoates)

摘要

Biobased/green composites were successfully developed from low cost recycled newspaper fibers and a poly(hydroxyalkanoate) i.e. poly(3-hydroxybutyarate), PHB by extrusion followed by injection molding process. Such biobased/green composites were fabricated having 30 and 40wt% of recycled newspaper fiber contents. The recycled newspaper fiber reinforced polypropylene (PP) based composites were also developed having similar fiber loadings. Mechanical, thermal, thermo-mechanical and morphological properties of PHB based composites were evaluated and a comparative property analysis was performed with PP based composites. Tensile modulus of PHB was improved by about 93 and 150% at 30 and 40 wt% of recycled newspaper fiber contents respectively. At 40wt% of recycled newspaper fiber content, the PHB based composites had shown superior tensile modulus (3.5 GPa) as contrast to PP based composite (3.0 GPa). The heat deflection temperature (HDT) of neat PHB matrix was improved by about 49% on reinforcement with 40 wt% newspaper fiber. The coefficient of linear thermal expansion (CLTE) of PHB reduced by 60% on reinforcement of 40 wt% of recycled newspaper fiber contents. The PHB based composite had shown superior heat deflection temperature (HDT) and lower coefficient of linear thermal expansion (CLTE) values than that of PP based composites. The morphology of PHB based composites had also shown better dispersion of fiber, lesser fiber pullouts and cavity formations as compared to PP based composites.