Polypropylene/natural rubber thermoplastic vulcanizates by eco-friendly and sustainable electron induced reactive processing

The Microstructure of GNR and the Mechanical Properties of Biobased PLA/GNR Thermoplastic Vulcanizates with Excellent Toughness

A series of different contents of glycidyl methacrylate (GMA)-grafted natural rubber (GNR) copolymers were fabricated via green bulk melt-grafting reactions, and super-tough bio-based poly (lactic acid) (PLA)/GNR thermoplastic vulcanizates (TPVs) were achieved by in-situ dynamic vulcanization. Increasing the graft yield, gel fraction, and crosslinking density of GNR vulcanizates effectively improved the ductility of the PLA/GNR TPVs, while prolonging the dynamic vulcanization time and increasing the GMA graft yield led to a notable enhancement in the impact toughness of the PLA/GNR TPVs. PLA/30 wt % GNR TPVs exhibited a significantly increased elongation (410%) and notched impact strength (73.2 kJ/m²), which were 40 and 15 times higher than those of the PLA/30 wt % NR TPVs, respectively. The new bio-based PLA/GNR TPVs offer promise as replacements for petroleum-based polymers in the automotive, 3D printing, and packaging fields.

Dynamically vulcanized biobased polylactide/natural rubber blend material with continuous cross-linked rubber phase

We prepared a biobased material, dynamically vulcanized polylactide (PLA)/natural rubber (NR) blend in which the cross-linked NR phase owned a continuous network-like dispersion. This finding breaks the traditional concept of a sea-island morphology formed after dynamic vulcanization of the blends. The scan electron microscopy and dissolution/swell experiments provided the direct proof of the continuous cross-linked NR phase. This new biobased PLA/NR blend material with the novel structure is reported for the first time in the field of dynamic vulcanization and shows promise for development for various functional applications.