Compatibilization of Poly(Lactic Acid) (PLA) and Bio-Based Ethylene-Propylene-Diene-Rubber (EPDM) via Reactive Extrusion with Different Coagents

Abstract

Much effort has been made to enhance the toughness of poly (lactic acid) (PLA) to broaden its possible range of usage in technical applications. In this work, the compatibility of PLA with a partly bio-based ethylene-propylene-diene-rubber (EPDM) through reactive extrusion was investigated. The concentration of EPDM in the PLA matrix was in the range of up to 20%. The reactive extrusion was carried out in a conventional twin-screw extruder. Contact angle measurements were performed to calculate the interfacial tension and thus the compatibility between the phases. The thermal and mechanical properties as well as the phase morphology of the blends were characterized. A copolymer of poly (ethylene-co-methyl acrylate-co-glycidyl methacrylate) (EMAGMA) was used as compatibilizer, which leads to a significant reduction in the particle size of the dispersed rubber phase when compared with the blends without this copolymer. The use of EMAGMA combined with soybean oil (SBO) and a radical initiator enhances the elongation at break of the compound. The results indicate that the reduction of the particle size of the dispersed phase obtained with the compatibilizer alone is not sufficient to improve the mechanical properties of the blend system. The induced radical reactions also influenced the mechanical properties of the blend significantly.

Structural Features and Properties’ Characterization of Polylactic Acid/Natural Rubber Blends with Epoxidized Soybean Oil

“…These properties significantly limit the application of PLA in the polymer packaging manufacture. This flaw in the mechanical properties is eliminated by combining the PLA with other polymers [ 4 ] and elastomers [ 5 , 6 , 7 , 8 ], primarily natural rubber (NR), which is a natural biopolymer [ 9 ]. The PLA-NR based composites have been extensively studied; however, all the tests have pointed out the problem of insufficient compatibility among these polymers.…”

Crystallization, Structure and Significantly Improved Mechanical Properties of PLA/PPC Blends Compatibilized with PLA-PPC Copolymers Produced by Reactions Initiated with TBT or TDI

“…PLA is often modified by being blended with other polymers [ 11 , 12 , 13 , 14 , 15 ], as well as inorganic fillers [ 16 , 17 , 18 ], in order to enhance its crystalline ability and improve its mechanical and thermal properties. However, compatibilizers are required to improve the compatibility of PLA blend with other polymers [ 19 , 20 , 21 ]. Zhang et al [ 20 ] used polyurethane elastomer prepolymer (PUEP) as the active compatibilizer to obtain super-toughened PLA/thermoplastic polyurethane (TPU) blends by reacting the isocyanate ( NCO ) groups in PUEP with the -OH groups on both sides of the PLA molecule.…”

“…However, compatibilizers are required to improve the compatibility of PLA blend with other polymers [19][20][21]. Zhang et al [20] used polyurethane elastomer prepolymer (PUEP) as the active compatibilizer to obtain super-toughened PLA/thermoplastic polyurethane (TPU) blends by reacting the isocyanate (NCO) groups in PUEP with the -OH groups on both sides of the PLA molecule.…”

Effects of wood flour and MA-EPDM on the properties of fused deposition modeling 3D-printed poly lactic acid composites

“…Moreover, the hydrophobic PLA is not compatible with the hydrophilic wood flour (Morreale et al 2008). To overcome these problems, a small amount of maleic anhydride grafted ethylene propylene diene monomer (MA-EPDM), which is widely utilized as an elastomeric polymer, was added to impart durability to the composite material, dampen brittleness, and improve the compatibility between PLA and wood flour (Piontek et al 2020).…”