阻湿剂对麦秸秆/植物蛋白胶复合材料阻湿性能与微观结构的影响

Effects of moisture resistance agent on moisture resistance and microstructure of wheat straw/vegetable protein adhesive composites

为探讨阻湿剂氯化石蜡、甘油对麦秸秆/植物蛋白胶复合材料阻湿性能、微观结构及化学结构的影响,采用热压成型方法制得添加2种阻湿剂的复合材料。分别测试麦秸秆/植物蛋白胶复合材料的力学性能、吸水率和吸湿率变化,采用FTIR分析其官能团的变化,测试接触角分析其润湿性能,并用体视显微镜观察分析复合材料弯曲断面微观结构。结果表明:添加氯化石蜡麦秸秆/植物蛋白胶复合材料弯曲强度、弯曲弹性模量最大,比未添加复合材料分别提高67%、129%,添加甘油麦秸秆/植物蛋白胶复合材料冲击强度较大,比未添加复合材料提高44%;添加氯化石蜡和甘油麦秸秆/植物蛋白胶复合材料2h吸水厚度膨胀率小于未添加复合材料;随着吸湿时间的增加,3种复合材料吸湿率均呈上升趋势,其中添加氯化石蜡麦秸秆/植物蛋白胶复合材料吸湿平衡率最小为4.3%;添加氯化石蜡麦秸秆/植物蛋白胶复合材料的弯曲断面微观结构较好,内部结合紧密,表面纤维暴露较少,阻湿性最好。

In order to investigate the influence of moisture resistance agents chlorinated paraffin and glycerol on the moisture resistance,microstructure and chemical structure of wheat straw/vegetable protein adhesive composites,composites added with two moisture resistance agents were prepared by hot pressing molding method.The mechanical properties,water and moisture absorption rate variation of wheat straw/vegetable protein adhesive composites were measured respectively,and the functional group variations were analyzed by FTIR.The wettability was analyzed by testing contact angles,and the bending cross-section microstructure of the composites was observed by the stereo microscope.The results show that the maximum bending strength and bending elastic modulus of wheat straw/vegetable protein adhesive composites adding chlorinated paraffin increase by 67% and 129% respectively compared with those of wheat straw/vegetable protein adhesive composites without additive.The maximum impact strength of wheat straw/vegetable protein adhesive composites adding glycerol increases by 44%compared with that of wheat straw/vegetable protein adhesive composites without additive.The 2hthickness swelling rate of water absorption of the wheat straw/vegetable protein adhesive composites adding chlorinated paraffin and glycerol are generally smaller than that of composites without additive.With the moisture absorption time increasing,the moisture absorption rate of three composites increases,and the smallest rate of balanced moisture absorption of wheat straw/vegetable protein adhesive composites adding chlorinated paraffin is 4.3%.The bending cross-section microstructure of wheat straw/vegetable protein adhesive composites adding chlorinated paraffin is better than that of other composites,the inner surface is integrated tightly and the surface of the fiber is less exposed and the moisture resistance is the best.