Toughening of polylactide via in situ formation of polyurethane crosslinked elastomer during reactive blending |
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| Authors: | Xipo Zhao Zheng Ding Qiang Lin Shaoxian Peng Pengfei Fang |
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| Affiliation: | 1. School of Physics and Technology, Wuhan University, Wuhan, China;2. Hubei Provincial Key Laboratory of Green Materials for Light Industry, Collaborative Innovation Center of Green Light‐weight Materials and Processing, School of Materials Science and Engineering, Hubei University of Technology, Wuhan, China |
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| Abstract: | Polylactide (PLA)/polyurethane (PU) composites were prepared by reactive blending method with in situ formation of PU particles via the reaction between polyester polyol (PPG) and toluene‐2,4‐diisocyanate (TDI). The interfacial compatibility and adhesion between the PLA and PU phases were greatly improved by the reaction of the terminal hydroxyl groups of PLA and N?C?O groups of TDI forming graft copolymer, as confirmed by FTIR spectroscopy. The elongation at break and notch impact strength of PLA/PU composites increased considerably with increasing PU content, and the tensile strength of PLA/PU composites decreased slightly compared with that of pure PLA. Upon addition of 12 wt % PU, the elongation at break and notch impact strength increased to 175.17% and 10.96 kJ/m2, respectively, about 27 times and 5.4 times greater than the corresponding values for the pure PLA. The tensile strength decreased only slightly to 48.65 MPa. The excellent interfacial adhesion, the dispersed PU elastomeric particles acting as stress concentration areas, and the triggering of large matrix shear yield as well as many fibrils by internal cavitation were the main mechanical toughening mechanisms. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44383. |
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| Keywords: | biodegradable composites degradation elastomers mechanical properties |
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