Fig. 2 shows the tensile properties of PLA/rubber
wood sawdust and PLA/CSR/rubber wood sawdust
composites. The PLA/rubber wood composites failed in
brittle mode. Both the tensile modulus and the tensile
strength increased as plotted in Figs. 2a and 2b. The
PLA/CSR/rubber wood sawdust composites showed a
rather similar manner but at lower rate. The tensile
moduli of the PLA/rubber wood sawdust and the
PLA/CSR/rubber wood sawdust composites increased
rapidly with the rubber wood content. Reinforcing PLA
and PLA/CSR with the wood sawdust clearly made the
composites stiffer and more brittle, this behavior was
observed in other WPCs such as PP/Meranti sawdust
composites[7], polylactide/pine wood composites[24] and
poly(vinyl chloride)/Balau sawdust composites[25]. In
comparison, toughening PLA with 5 wt% CSR made
the PLA/rubber wood composites less stiff.