湿固化聚氨酯热熔胶中试研究  

Pilot study on moisture-cured polyurethane hot melt adhesive

作　　者：刘晨 杨淑怡[1] 张梦婷 李翔 曾赟 兰支利 曾声红[1] 郑和根 Liu Chen;Yang Shuyi;Zhang Mengting;Li Xiang;Zeng Yun;Lan Zhili;Zeng Shenghong;Zheng Hegen(Jiangxi Yongfeng Industrial Zone Management Committee,Ji'an 331500,Jiangxi,China;College of Chemistry and Chemical Engineering,Hunan Normal University,Changsha 410081,Hunan,China)

机构地区：[1]江西永丰工业园区管理委员会,江西吉安331500 [2]湖南师范大学化学化工学院,湖南长沙410081

出　　处：《中国胶粘剂》2025年第2期36-42,共7页China Adhesives

摘　　要：在前期250 mL烧瓶试验基础上,本研究采用20 L反应釜进行中试试验。从聚酯多元醇原料、催化剂、温湿度以及扩链剂等方面,研究其对湿固化聚氨酯热熔胶性能的影响,并通过黏度、粘接强度和表干时间等方法对合成材料进行表征。研究结果表明:(1)中试试验不同于小试加料可以是固体或液体,中试在加料方式上尽量采用液体,让合成产物分子量均匀,另外中试需要考虑降温和出料问题。(2)结晶性高的原料会使初始剥离强度增大,但最终剥离强度却先升高后降低,当结晶度太高时,最终剥离强度反而要下降。表干时间随着结晶度提高而缩短。(3)催化剂能提高湿固化聚氨酯热熔胶的粘接力,三乙烯二胺的催化效果最佳,但是催化剂用量对热熔胶的黏度有影响,催化剂用量过多会导致热熔胶凝胶。试验结果表明,三乙烯二胺质量分数选择0.5%时,性能相对最佳。(4)温度、湿度对湿固化聚氨酯热熔胶的粘接力有影响,湿度越高,水汽渗透到胶层越容易,加速—NCO反应,生成极性强的氨基甲酸酯键和脲键等化学键。(5)扩链剂可以使得聚合物分子量增大、黏度增大,基材上受力点密度增大,从而提高粘接力;但用量过多或官能度高时,分子链之间交联程度越高,胶粘剂容易凝胶。中试试验选择1,4-丁二醇(BDO),扩链消耗10%的—NCO的方案最佳。(6)中试研究认为,真空度≤-0.09 MPa,减压真空脱水2 h,聚氨酯预聚体合成温度在(80±5)℃,反应时间2 h,扩链反应30 min~1 h,异氰酸酯液体投料,催化剂(三乙烯二胺)用量为0.5%,扩链剂(1,4-丁二醇)添加量消耗剩余—NCO(物质的量分数)为10%时,制备的聚氨酯热熔胶性能相对最佳。On the basis of the preliminary 250 mL flask experiment,the pilot-scale experiment was conducted by using a 20 L reactor in this study.The effects of polyester polyol raw materials,catalysts,temperature,humidity,and chain extenders on the properties of moisture-cured polyurethane hot melt adhesive were investigated,and the synthesized materials were characterized by using methods such as viscosity,bonding strength,and surface drying time.The research results showed that,(1)The pilot experiment was different from the small-scale experiment in that the feeding of the small-scale experiment could be solid or liquid.In the pilot experiment,liquid was used as much as possible in the feeding method to make the molecular weight of synthesized product uniform.In addition,in the pilot experiment,cooling and discharge issues needed to be considered.(2)Raw materials with high crystallinity could increase the initial peel strength,but the final peel strength first increased and then decreased.When the crystallinity was too high,the final peel strength actually decreased.The surface drying time decreased with increasing crystallinity.(3)The catalyst could improve the adhesion of moisture-cured polyurethane hot melt adhesive,and the catalytic effect of triethylenediamine was the best,but the amount of catalyst had an impact on the viscosity of hot melt adhesive,and excessive amount of catalyst could cause hot melt adhesive to gel.The test results indicated that the performance was relatively optimal when the mass fraction of triethylenediamine was selected as 0.5%.(4)Temperature and humidity had an impact on the bonding strength of moisture-cured polyurethane hot melt adhesive.The higher the humidity,the easier it was for water vapor to penetrate into the adhesive layer,accelerating the—NCO reaction and generating highly polar chemical bonds such as urethane and urea bonds.(5)Chain extender could increase the molecular weight and viscosity of polymer,increase the density of stress points on the substrate,and thus improve the

关 键 词：聚氨酯热熔胶 聚酯多元醇 异氰酸酯 扩链剂 粘接强度 

分 类 号：TQ436.4[化学工程]