Fabrication of PLLA with High Ductility and Transparence by Blending with Tiny Amount of PVDF and Compatibilizers

Abstract

Poly(L‐lactic acid) (PLLA) with high ductility and transparence is fabricated by a blending tiny amount of polyvinylidene fluoride (PVDF) and reactive comb compatibilizers (RCC). Upon blending, the reaction between terminal carboxyl groups in PLLA and expoxy groups in RCC produces graft copolymer (PLLA‐g‐poly(methyl methacrylate) (PMMA)), which locates at the PVDF/PLLA interface due to the balanced stress on two sides. On the one hand, the PVDF domain size decreases remarkably with the help of compatibilization, accounting for the excellent transparence. On the other hand, the interface is enhanced significantly, resulting in an activated PLLA layer surrounding PVDF domains. The thickness exhibits higher magnitude because of the high molecular weight of grafted PLLA (relative to premade compatibilizers). During uniaxial tension, the activated PLLA layers (in addition to PVDF) can cause effective energy absorption and dissipation in the case of percolation of them, which is the reason for the better ductility. These results provide an efficient strategy to improve the ductility and transparence simultaneously.

Supertough Poly(lactic acid) and Sustainable Elastomer Blends Compatibilized by PLLA-b-PMMA Block Copolymers as Effective A-b-C-Type Compatibilizers

“…Blending PLA with renewable elastomers is one of the most economically attractive and scalable methods to achieve high-performance PLA materials. − However, the poor compatibility between PLA and additive elastomers greatly limits these PLA/elastomer blends in achieving satisfying toughness. − Adding block or graft copolymers as compatibilizers has been proven to be a highly efficient approach for improving the miscibility of the components in polymer blends. − For example, Hillmyer and et al reported that the addition of polyethylene (PE)- b -poly (L-lactic acid) (PLLA) copolymers into PLLA/low-density polyethylene (LDPE) blends dramatically improved their toughness because of the enhancement of interfacial adhesion and the reduction of the LDPE particle size. , In PLA and other flexible biobased polyester blends, block copolymers containing the PLA block were also demonstrated to be highly efficient compatibilizers for improving the compatibility and performance of the blends, such as in the use of PLA- b -poly­(butylene succinate) (PBS) block copolymers for PLA/PBS blends, PLA- b -poly­(ε-caprolactone) (PCL) block copolymer for PLA/PCL blends, and so forth. − However, most of the reports employed A- b -B block copolymers having the same chemical structure as the two blend components in these PLA-based blends. Because of lack of efficient synthesis methods, the preparation of A- b -B block copolymers is a great challenge for many PLA (A) and elastomer (B) blends. − In addition, the A- b -B block copolymers are generally unsuitable for compatibilizing the PLA phase with other kinds of elastomers.…”

Strengthened Poly(vinylidene fluoride)/Epoxidized Natural Rubber Blend by a Reactive Compatibilizer Based on an Amino Acid-Modified Fluorocarbon Elastomer

“…As shown in Figure , the morphology was significantly changed with the addition of FKM-AHA10 for 5 and 7 php, where the PVDF phase partly became a dispersed phase. At the same time, at high FKM-AHA10 loading, it may preferentially form micelles in the ENR50 domain rather than located at the interface. − …”

Comparative Study of Crystallization, Mechanical Properties, and In Vitro Cytotoxicity of Nanocomposites at Low Filler Loadings of Hydroxyapatite for Bone-Tissue Engineering Based on Poly(l-lactic acid)/Cyclo Olefin Copolymer

“…Increasing the nHA wt% resulted in both decreasing UTS and elongation at the breakpoint. PLLA/PVDF blends showed improved ductility in the presence of compatibilizers [42]. COC in PLLA/COC10-nHA resulted in strong and ductile polymer; thus, its nanocom-posite with nHA showed elongation at breakpoint at higher strain percent values than PLLA/nHA.…”