淀粉基木材胶粘剂的合成及性能研究

Study on the synthesis and property of starch based wood adhesive

以玉米淀粉为接枝骨架,过硫酸铵为引发剂,与接枝单体乙酸乙烯酯-丙烯酸乙酯进行接枝共聚反应,制取淀粉基木材胶粘剂。对得到的淀粉接枝共聚物进行了表征分析及性能研究。IR谱图表明,样品除了保持淀粉的特征吸收峰外,在1730～1740cm-1之间出现了羰基特征吸收峰;X-粉末衍射谱图表明,样品多为弥散峰,证明淀粉接枝共聚物基本为少量结晶态与无定形态共存的结构;TG、DTA曲线证实了接枝共聚反应的发生,且淀粉接枝共聚物的热稳定性优于纯玉米淀粉;性能测试结果表明,制备的胶粘剂具有较好的高温稳定性、粘接性、耐寒性和储存稳定性;各项指标已达到了国家标准HG/T2727-95中聚乙酸乙烯酯木材胶粘剂的性能指标,特别是压缩剪切干强度远远超过了国家标准。

The graft copolymerization of vinyl acetate and ethyl acrylate onto corn starch was carried out using ammonium persulfate as initiator. The starch graft copolymer after purification was characterized, and its properties were determined. IR spectra of graft copolymers existed the carbonyl group characteristic absorption peak at 1730- 1740cm^-1 besides the characteristic absorption peak of starch. The several dispersion peaks of XRD showed that the graft copolymers were the concomitant product of a little crystalline region and amorphous state;TG and DTA curves confirmed the occurrence of graft copolymerization, and showed that the thermal stability of starch eopolymer was better than that of pure corn starch. Production of starch based wood adhesive was white or cream white emulsion paste, excellent emulsive properties. It had a good high temperature stability, good adhesiveness, good cold endurance and good stability for storage. All properties of starch based wood adhesive reached national standard HG/T2727-95 of polyvinyl acetate wood adhesive. Especially compressive shear dry strength was over the national standard enormously.