Super-tough Poly(lactide) Thermoplastic Vulcanizates Based on Modified Natural Rubber

In order to take advantage of the sustainability and environmental friendliness of a biobased poly(lactide) (PLA), it was used with natural rubber graft-modified glycidyl methacrylate (NR-GMA), via bulk free radical polymerization, to produce a new thermoplastic vulcanizate (TPV) by in situ dynamical vulcanization. The well-dispersed super-tough PLA-based thermoplastic vulcanizate with 20 wt % NR-GMA exhibited a greatly improved notched impact strength of 73.4 kJ/m(2) and elongation yield of 136%, which represented a 26 and 33-fold increase, respectively, compared to neat PLA. Interfacial reactive compatibilization between the PLA matrix and NR-GMA phase was confirmed by Fourier transform infrared spectroscopy (FT-IR) and dynamic mechanical analysis (DMA) and differential scanning (DSC) measurements. This strong interfacial interaction, in combination with a fine microscale and nanoscale dispersed phase structure, were responsible for the high toughness of PLA/NR-GMA TPV. These new PLA-based vulcanizates have the potential for application in electrical devices, packaging, and 3D printing materials.