Scholarlink

<p>Interfacial failure in glass-fiber-reinforced polypropylene (GF/PP) composites is widely recognized to initiate within the fiber–matrix interphase, yet the specific molecular bonds responsible for fracture initiation remain unclear. Here, we identify the weakest chemical link governing fracture initiation in GF/PP composites through bond-resolved reactive molecular dynamics simulations. Using the ReaxFF force field, we explicitly model the complete load-transfer pathway across the epoxy–glass interface, the cross-linked epoxy network, and the epoxy–PP-g-MA coupling motifs. By directly tracking bond deformation and rupture during tensile loading, we establish a hierarchy of bond stability within the interphase architecture. Across all investigated interfacial motifs, local bond dissociation consistently initiates at C–O bonds within epoxy-containing units at the lowest tensile strain. These findings identify the epoxy-rich sizing layer as the intrinsic molecular trigger of fracture initiation within the GF/PP interphase and demonstrate that damage originates from chemically localized bond rupture rather than from loss of interfacial adhesion alone. By pinpointing the molecular origin of interphase fracture, this work provides mechanistic insight into damage initiation and establishes molecular design guidelines for strengthening GF/PP composites through targeted modification of sizing chemistry, cross-link architecture, and compatibilizer design.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Revealing the weakest chemical link in the interphase of glass-fiber/polypropylene composites

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2026年7月2日

查看全文
  • V. Sorkin,
  • P. Liu,
  • Zachary Aitken,
  • J. H. Kong,
  • C. B. He,
  • Y. W. Zhang

摘要

Interfacial failure in glass-fiber-reinforced polypropylene (GF/PP) composites is widely recognized to initiate within the fiber–matrix interphase, yet the specific molecular bonds responsible for fracture initiation remain unclear. Here, we identify the weakest chemical link governing fracture initiation in GF/PP composites through bond-resolved reactive molecular dynamics simulations. Using the ReaxFF force field, we explicitly model the complete load-transfer pathway across the epoxy–glass interface, the cross-linked epoxy network, and the epoxy–PP-g-MA coupling motifs. By directly tracking bond deformation and rupture during tensile loading, we establish a hierarchy of bond stability within the interphase architecture. Across all investigated interfacial motifs, local bond dissociation consistently initiates at C–O bonds within epoxy-containing units at the lowest tensile strain. These findings identify the epoxy-rich sizing layer as the intrinsic molecular trigger of fracture initiation within the GF/PP interphase and demonstrate that damage originates from chemically localized bond rupture rather than from loss of interfacial adhesion alone. By pinpointing the molecular origin of interphase fracture, this work provides mechanistic insight into damage initiation and establishes molecular design guidelines for strengthening GF/PP composites through targeted modification of sizing chemistry, cross-link architecture, and compatibilizer design.