分别采用碱、硅烷偶联剂(A-1120).K阻燃剂(硼砂-HCHO-NaHS03)对剑麻纤维进行表面处理,通过模压成型工艺制备了剑麻纤维/酚醛树脂(SF/PF)共混复合材料。采用动态力学性能测试(DMA)研究了SF表面处理方法对SF/PF共混复合材料动态力学性能、蠕变及应力松弛性能的影响,采用扫描电镜(SEM)观察了SF/PF共混复合材料冲击断面的形态。结果表明,SF经偶联剂处理后,SF/PF共混复合材料的储能模量达到6310MPa,玻璃化转变温度(Tg)达到216℃,其储能模量和Tg分别比未处理复合材料提高2倍和150℃;SF经阻燃剂处理后,SF/PF共混复合材料的蠕变和应力松弛性能得到提高,SEM观察表明,SF表面处理对提高材料的界面粘接性具有一定的作用。
In this work, sisal fiber (SF) was pretreated hy alkali, silane coupling agent A-1120 and flame retardant respectively. Sisal fiber/phenol formaldehyde (SF/PF) composites were prepared through compression molding. Effects of three treatments on the dynamic mechanical properties, creep and stress relaxation behavior were studied by dynamic mechanical analysis (DMA). Fracture surfaces of broken specimens of the composites were examined by scanning electron microscope (SEM).o The results indicate that the storage modulus and glass transition temperature of the composites is increased enormously respectively, the storage modulus of the composite arrives at 6310 MPa, 3 times of the untreated SF reinforced composite, the glass transition temperature of the composite is improved by 15℃, due to silane 'coupling agent treatment. The behaviors of the stress relaxation and creep are improved to a great extend due to flame retardant treated fiber. SEM of fractured surfaces of untreated and trdated SF/PF composites clearly demonstrated better fiber-matrix bonding in the case of the latter.