• 文献标题:   How graphene oxide affects shape memory properties and strength of poly(l-lactide-co-epsilon-caprolactone)
  • 文献类型:   Article
  • 作  者:   ZHANG XJ, YANG QS, LENG JS
  • 作者关键词:   graphene oxide, shape memory polymer composite, molecular dynamic, shape memory effect, covalent bond
  • 出版物名称:   JOURNAL OF INTELLIGENT MATERIAL SYSTEMS STRUCTURES
  • ISSN:   1045-389X EI 1530-8138
  • 通讯作者地址:   Beijing Univ Technol
  • 被引频次:   0
  • DOI:   10.1177/1045389X20942581 EA JUL 2020
  • 出版年:   2020

▎ 摘  要

Poly(l-lactide-co-epsilon-caprolactone) is an environment-friendly shape memory polymer. Molecular dynamics method was used to study the shape memory effect and mechanical properties of graphene oxide-reinforced poly(l-lactide-co-epsilon-caprolactone) to understand the microscopic mechanism. Two models containing dispersed graphene oxide were constructed. It is shown that the addition of graphene oxide causes the glass transition temperature of material to rise because of limitation on polymer activity. The uniaxial tensile properties of the composites were studied. The results exhibited that strength of composites depend on the interface state of the polymer and graphene oxide. The strength of the composite with covalent bond is much higher than that of another without the covalent bond between graphene oxide and poly(l-lactide-co-epsilon-caprolactone) generated. Stress softening effect was observed in the cross-linked composite in the glass state. Their uniaxial tension thermodynamic cycles were carried out to consider the shape memory effect of the composites. It is shown that graphene oxide-reinforced composites with different interactions exhibit fair shape memory effect in the direction of paralleling graphene oxide surface. In terms of the direction perpendicular to graphene oxide sheet, the fixed ratios of the composites decrease slightly about 1.64%-3.63%, and the recovery ratios of the composites with the covalent bond are higher than others about 3.22%-12.93%.