硅烷改性PPTA纤维的表面粘结性能研究

Study on surface adhesion of silane modified PPTA fiber

采用未干燥的聚对苯二甲酰对苯二胺(PPTA)纤维,以乙烯基三甲氧基硅烷(VTMS)溶液对其进行表面改性,分析了改性前后PPTA纤维的表面元素、形貌结构以及力学性能的变化,并通过微脱胶法和激光拉曼光谱法研究了PPTA纤维/环氧树脂复合材料的界面剪切强度。结果表明:经VTMS溶液改性后,PPTA纤维表面产生了新的极性官能团,表面粗糙度增加;随着VTMS溶液浓度增大或处理时间增加,PPTA纤维/环氧树脂界面剪切强度逐渐增大,PPTA纤维的力学性能略为降低;较佳改性处理条件为VTMS溶液质量分数6%,处理时间5 min;经VTMS溶液改性处理后,PPTA纤维与树脂间的粘接性能提高,延缓了纤维轴向应力的传递。

An undried poly- p -phenylene terephthamide （PPTA） fiber was exposed to the surface modification using vinyhrim- ethoxy silane （VTMS） solution. The change in the surface element, morphology and mechanical properties of PPTA fiber was an- alyzed before and after the modification. The interracial shear strength of PPTA fiber/epoxy resin composite was studied by micro- debonding method and Raman spectroscopy. The results showed that the surface of PPTA fiber became rougher due to the genera- tion of new polar functional groups after VTMS solution modification; the interracial shear strength of PPTA fiber/epoxy resin composite was gradually increased and the mechanical properties of PPTA fiber were slightly decreased as the concentration of VTMS solution was increased or the treating time was prolonged ; the proper modification conditions should be as followed： 6% VTMS solution by mass fraction, treating time 5 min; and the surface adhesion rose between PPTA fiber and resin, causing the fiber axial stress transfer to delay after modification.