【摘要】 在总结高分子材料增韧机理、高分子纳米复合材料冲击破坏行为的基础上,探讨了高分子纳米复合材料的增韧机理。纳米无机粒子起应力集中的作用导致界面脱黏、空化与基体屈服是其增韧高分子材料的主要原因,而碳纳米管则起桥联裂纹、偏转裂纹方向、传递界面应力使聚合物基体屈服而增韧高分子材料。对聚合物/层状填料纳米复合材料而言,分散在聚合物基体中的插层或剥离的无机纳米片层对复合材料银纹的形成有抑制作用,其二维几何结构不利于片层周围基体的屈服与界面脱黏、空化,因而不能增韧高分子材料,反而还导致了聚合物/层状填料纳米复合材料抗冲击强度的降低。高分子材料的纳米复合目前很难达到橡胶增韧的效果,若同时采用纳米复合技术与官能化弹性体增韧技术,可望设计、制备出一系列高强度、高韧性的高分子纳米复合材料。更多还原

【Abstract】 The toughening mechanisms of polymer-matrix nano-meter composites were discussed based on reviewing the toughening mechanisms of polymeric materials and the fracture behaviours of nano-meter composites.The stress concentration of rigid inorganic nano-meter particles induced the interfacial de-bonding,cavitation and yielding of the matrix,which led to the toughening of the polymer/inorganic particle nano-meter composites.For polymer/carbon nano-meter tube(CNTs)nano-meter composites,the crack-bridging,crack de?ection and interfacial stress transfer of CNTs induced to yield the polymer matrix,resulting in the toughening of the nano-meter composites.For polymer/layered filler nano-meter composites,the intercalted or exfoliated nano-meter layers uniformly disered in the polymer matrix inhibited the crazing of the polymer matrix,their two dimensional structure restrained the yielding of matrix,the interfacial de-bonding and cavitation,resulted in the decrease of the impact toughness of the composites.Till now,the impact toughness of polymer-matrix nano-meter composites was lower than that of rubber-toughened polymeric materials.The combination of compounding in nano-meter level and toughening by functional elastomer would provide a chance to design and produce a series of high-strength and high-toughness polymer nano-meter composites.更多还原