139. Supertough Polylactide Materials Prepared through In Situ Reactive Blending with PEG-Based Diacrylate Monomer
作者：Huagao Fang, Feng Jiang, Qianghua Wu, Yunsheng Ding, and Zhigang Wang*
關鍵字：超韌性聚乳酸，反應性共混，共混物
論文來源：期刊
具體來源：ACS Appl. Mater. Interfaces, 2014, 6 (16), 13552–13563
發表時間：2014年
Supertough biocompatible and biodegradable polylactide materials were
fabricated by applying a novel and facile method involving reactive
blending of polylactide (PLA) and poly(ethylene glycol) diacylate
(PEGDA) monomer with no addition of exogenous radical initiators. Torque
analysis and FT-IR spectra confirm that cross-linking reaction of
acylate groups occurs in the melt blending process according to the free
radical polymerization mechanism. The results from differential
scanning calorimetry, phase contrast optical microscopy and transmission
electron microscopy indicate that the in situ polymerization of PEGDA
leads to a phase separated morphology with cross-linked PEGDA (CPEGDA)
as the dispersed particle phase domains and PLA matrix as the continuous
phase, which leads to increasing viscosity and elasticity with
increasing CPEGDA content and a rheological percolation CPEGDA content
of 15 wt %. Mechanical properties of the PLA materials are improved
significantly, for example, exhibiting improvements by a factor of 20 in
tensile toughness and a factor of 26 in notched Izod impact strength at
the optimum CPEGDA content. The improvement of toughness in PLA/CPEGDA
blends is ascribed to the jointly contributions of crazing and shear
yielding during deformation. The toughening strategy in fabricating
supertoughened PLA materials in this work is accomplished using
biocompatible PEG-based polymer as the toughening modifier with no toxic
radical initiators involved in the processing, which has a potential
for biomedical applications.