Highly toughened and heat-resistant poly(L-lactide)/polyvinylidene fluoride materials through simply interfacial interaction control via epoxy chain extender

In this work, polylactide (PLA)-based materials with excellent rigid-toughness balance and high heat distortion temperatures (HDT) was prepared by regulating the interfacial state of the PLA/polyvinylidene fluoride (PVDF) blends. A multifunctional epoxy chain extender (ADR) was employed to control the interfacial properties of incompatibility PLA/PVDF blend, and the effects of ADR on the structure and properties of the blends were studied systematically. The torque data showed that the incorporation of ADR could lead to the formation of crosslink structure in PLA matrix via the reaction between ADR and PLA, which was positive for changing the viscosity of PLA/PVDF and regulating the interfacial structure of PLA/PVDF blends. DSC data revealed that the introduction of ADR could limit the movement of the PVDF chain. Rheological behavior and DMA data demonstrated that ADR could significantly enhance the interaction force between PLA and PVDF. When the ADR content was 1.5 wt%, the tensile strength, the elongation at break, the notch impact strength, and the heat distortion temperature of the material reached 58.55 MPa, 75.01 %, 44 kJ/m2, and 73.8 celcius, respectively, which was increased respectively by 7 %, 22 times, 1.5 times, and 42 % compared with additive-free PLA/PVDF blend.