Enhancing Mechanical and Shape Memory Properties of Polylactide/polyamide Elastomer Blends Via Reactive Blending with a Chain Extender

The structure and properties of incompatible polylactide (PLA)/polyamide elastomer (PAE) blends were tailored by a chain extender specifically the styrene-glycidyl acrylate copolymer Joncryl ADR4368 (ADR). Various PLA/PAE/ADR blends with different compositions were prepared by melt blending, and their morphology, crystallization behavior, and mechanical and the shape memory properties were systematically investigated. The results showed a uniform dispersion of PAE particles in the PLA matrix for the PLA blends with a reduction in particle size upon the addition of ADR. The crystallization of PLA was retarded, which was confirmed by a decrease in the melt crystallization temperature and an increase in cold crystallization temperature in the PLA/PAE/ADR blends. Rheological analysis showed an improvement in the melt elasticity of the PLA/PAE binary blend due to the presence of ADR, possibly attributed to the formation of long-chain-branched copolymers at the interface. Notably, the PLA/PAE/ADR blend exhibited superior toughness, featuring an elongation at break of 288% and a notched impact strength of 37 kJ center dot m-2, along with a high shape memory fixation rate and recovery rate when the ADR content was 1 wt%. Furthermore, the underlying toughening mechanism was elucidated. This work may offer an industrially scalable relevant model to fabricate high-performance PLA materials. A chain extender ADR was added to polylactide (PLA)/polyamide elastomer (PAE) blend in an effort to improve the compatibility of PLA and PAE. The results showed that ADR could react with the end groups of PLA and PAE, which increased the complex viscosity, toughness, and the shape recovery rate of PLA/PAE blend.image