脲基超支化聚合物木材胶黏剂的合成与性能

Synthesis and Properties of Ureido Hyperbranched Polymer Wood Adhesives

脲基通常由异氰酸酯与氨基反应产生,由于异氰酸酯对人体健康和环境具有较大的危害且成本较高,因此利用低成本的尿素替代异氰酸酯合成脲基聚合物胶黏剂的途径正越来越受到关注。文中利用廉价的丙烯酸甲酯和对苯二胺为原料,通过迈克尔加成反应和酰胺化反应合成了树枝状四元胺,再与尿素在无催化剂和无溶剂的条件下进行A_(2)+B_(4)熔融缩聚,得到一系列低成本无醛的超支化脲基聚合物胶黏剂。利用核磁共振、红外光谱、质谱、凝胶渗透色谱等方法验证了其结构;差示扫描量热分析和热重分析表征了其热行为和热稳定性。最后将该脲基聚合物作为胶黏剂黏接不同基材,结果表明,粘接木材的剪切强度大于1.34MPa,远远高于GB/T17657-2013对II类板的要求,且其具有良好的耐水性;用于黏接有机玻璃、钢化玻璃、聚四氟乙烯、橡胶、玛瑙等基材也表现出较强的黏接力。

Ureido groups are usually produced by the reaction of isocyanate and amino groups.Because isocyanate is harmful to human health and environment,and the cost is high,more and more attention has been paid to the synthesis of ureido polymer adhesives by using low-cost urea instead of isocyanate.In this paper,a series of low-cost formaldehyde-free hyperbranched ureido polymer adhesives were synthesized from cheap methyl acrylate and p-phenylenediamine by Michael addition reaction and amidation reaction,and then fused with urea by A_(2)+B_(4) polycondensation without catalyst and solvent.The NMR,FT-IR,MS and GPC were used to analyze and verify their structure;DSC and TGA were used to analyze their thermal behavior and thermal stability.Finally,the ureido polymer was used as adhesive to bond different substrates.The results show that the bonding strength of bonding wood is more than 1.34 MPa,much higher than requirements of Type II Plywoods in China National Standard(GB/T 17657-2013),and it has good water resistance;used for bonding polymethyl methacrylate,tempered glass,polytetrafluoroethylene,rubber,agate and other substrates,it also shows a strong adhesion.