热处理对聚合物改性纤维增韧水泥基复合材料物理力学性能的影响

Effect of Heat Treatment on Physical and Mechanical Properties of Polymer Modified Fiber Reinforced Cementitious Composites

采用环氧乳液、乳胶粉制备了聚合物改性纤维增韧水泥基复合材料,研究了200℃、400℃、600℃、800℃热处理对材料物理力学性能的影响。结果表明:掺加聚合物可以改善试样的高温体积稳定性,使得试样在800℃高温下热处理时不发生爆裂;室温冷却条件下,聚合物使得材料峰值残余强度对应的温度由400℃降低至200℃,而在水冷却条件下,试样的残余强度随着热处理温度的升高持续降低,800℃热处理后聚合物改性试样在水冷却时溃散;聚合物分解在试样内部形成的交联孔道,改善了试样热处理后的孔结构,延缓了高温热处理对试样力学性能的劣化速率。

Polymer modified fiber reinforced cementitious composites were prepared by epoxy emulsion and emulsion powder.The effects of heat treatment at 200℃,400℃,600℃and 800℃on the physical and mechanical properties of the composites were studied.Results show that high temperature volume stability of specimen is improved by adding polymer.There is no cracking of specimens with polymer during heat treatment at 800℃.The temperature corresponding to the peak value of residual strength decreases from 400℃to 200℃under the condition of air cooling.The residual strength of specimens decreases continuously as the temperature of the heat treatment increases under water cooling.The polymer modified fiber reinforced cementitious composites collapses during water cooling after heat treatment at 800℃.The cross-linking channels formed by polymer decomposition in the specimen improve the pore structure of heat-treated specimen,which delays the degradation rate of high temperature heat treatment on the properties of the sample.