淀粉基木材胶黏剂的制备与性能.doc

淀粉基木材胶黏剂的制备与性能 刘宥辰 B化工112 111031238 摘要: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-丙烯酸丁酯进行接枝共聚反应,制取淀粉基木材胶黏剂。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,制备的胶黏剂具有较好的高温稳定性、粘接性,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黏剂的性能指标,特别是压缩剪切干强度远远超过了国家标准。 关键词:玉米淀粉;淀粉基木材胶黏剂;接枝共聚 Preparation and Properties of Starch Based Wood Adhesive LIU Youchen Abstract: The graft copolymerization of vinyl acetate and butyacrytate on to corn starch w as carried out using ammonium per sulfate as initiator. Thestarch graft copolymer after purification w as characterized, and its properties w ere determined. IR spectra of graft copolymers indicated that the carbonyl group characteristic absorption peak existed at 1730 ~ 1740 cm- 1 besides that of starch. The XRD pattern showed there were several dispersion peaks, therefore the graft copolymers was the concomitant structure of a little crystalline state and amorphous state. TG and DTA curves confirmed the occurrence of graft copolymerization, and showed that the thermal al stab alit of starch copolymer w as better than that of pure corn starch. Production of starch based wood adhesive is white or cream white emulsion paste, excellent emulsive properties. It has good high temperature stability, good adhesiveness. All properties of starch based wood adhesive can meet the national standard HG /T2727 - 95 of polyvinyl acetate wood adhesive, and the compressive shear strength outdistances the nation al standard especially. Keywords: Corn starch; starch based wood adhesive; grafting copolymerization 前言 近年来,由于淀粉具有可再生性强、来源广泛、种类繁多、环境友好及价格低廉等优点,重新引起了人们的重视,以淀粉为原料生产木材胶黏剂已成了一种发展的趋势 [1~3] 。传统的淀粉基胶黏剂由于耐 水性差、初黏力小和干燥速度慢等缺点,使其应用范围受到很大程度的限制,为了寻求高质量的胶黏剂,人们采用接枝聚乙烯醇[4] 、丙烯酸系共聚物 [5] 、醋 酸乙烯酯和丙烯酸异辛酯 [6] 等方法对玉米淀粉胶黏 剂进行改性。 本研究以过硫酸铵为引发剂进行了玉米淀粉与乙酸乙烯酯-丙烯酸丁酯两种单体对玉米淀粉的接枝共聚改性,合成出一种具有干燥速度快、剪切强度大、耐水性强等优点的乳液淀粉基木材胶黏剂。并 对得到的淀粉接枝共聚物进行了表征分析及性能研究。 1实验部分 1.1淀粉接枝共聚物的合成与后处理 1.1.1淀粉接