交联-接枝双重改性淀粉基木材胶黏剂的合成研究

Study on Synthesis of Crosslink and Graft Double-modified Wood Adhesives Based on Starch

以氧化淀粉为起始原料,环氧氯丙烷和丙烯酸乙酯(EA)为改性剂,制得了交联-接枝双重改性淀粉基木材胶黏剂。实验结果表明,较好的交联改性条件为:环氧氯丙烷质量分数为4.0%(相对于淀粉质量),氧化淀粉采用3∶2分步加料方式。正交试验得到的接枝改性条件为:过硫酸铵质量分数为0.2%,丙烯酸乙酯(EA)为10.0%,反应时间3 h,反应温度70℃。经过双重改性后,淀粉基木材胶黏剂的胶合强度(7.5 MPa)、耐水时间(48 h)和存储期(200 d)等指标可以达到GB/T 9846-2004标准要求。

Wood adhesives were prepared by crosslink and graft modification method with starch as raw materials,epichlorohydrin and ethyl-acrylate as chemical modifying agents respectively.Experiment results showed that the proper amount of epichlorohydrin was 4.0 wt%,and 60% starch should be put into reactor at starting and another 40% at interval of 2 h in the process of cross-linking.The optimum graft conditions determined by orthogonal design were as follows： ammonium persulfate 0.2wt%,ethyl-acrylate 10.0 wt%,reaction time 3h,reaction temperature 70 ℃.The wood adhesives has high bond strength（7.5 MPa）,good water-resistance（48 h）,stable storage stability（200 d）,which can meet the requirement of national standard GB/T 9846-2004.