竹纤维的表面包覆及其对浇注型聚氨酯弹性体力学性能的影响

通过一种异氰酸酯基团(—NCO)质量分数为14.5wt％的高活性聚氨酯(PU)包覆剂对竹纤维(BF)进行表面包覆获得包覆型竹纤维(PUBF),采用原位聚合法制备了包覆型竹纤维增强浇注型聚氨酯(PUBF/PU)弹性体复合材料.采用FTIR、SEM、XRD及接触角测试仪对PUBF及BF进行了表征.结果 表明,BF表面成功包...

Surface coating of bamboo fibres and its effects on the mechanical properties of casting polyurethane elastomer

The coated bamboo fibres (PUBF) were obtained by using high-reactivity polyurethane (PU) coating agent to coat bamboo fibres (BF), and the mass fraction of isocyanate group (—NCO) in PU coating agent was 14.5wt%. The PUBF/PU casting elastomer composites were prepared by in-stiu polymerization. The BF and PUBF were characterized by FTIR, SEM, XRD and contact angle testing. The results show that the surface of the BF is successfully coated by a thin layer of PU terminated with reactive amino groups (—NH₂), which improves the interface compatibility and interfacial bonding between the BF and the casting PU. When the mass fraction of PUBF in the composite is 3wt%, the viscosity of the prepolymer at 80℃ is only 2.2 Pa·s, which is close to the viscosity of the pure PU. The tensile and tear strengths of the corresponding PUBF/PU composite are 38.0 MPa and 82.9 kN/m, respectively, improved by 51.6% and 25.6% compared with the pure casting PU. The BF pre-coated by high-reactivity PU coating agent is suitable for preparing the PUBF/PU composite.