成膜物质对水性防火涂料膨胀阻燃性能的影响  

Effects of Binder Resins on Expansion and Flame-Retardant Performances of Waterborne Fire-Retardant Coatings

作　　者：范方强[1] 夏正斌[1] 李清英[1] 李忠[1] 陈焕钦[1] 

机构地区：[1]华南理工大学化学与化工学院,广东广州510640

出　　处：《华南理工大学学报（自然科学版）》2012年第9期26-31,37,共7页Journal of South China University of Technology(Natural Science Edition)

基　　金：广东高校产学研结合示范基地项目(cgzhzd0904)

摘　　要：以硅丙、纯丙、苯丙、醋叔聚合物乳液为成膜物质分别制备了多种用于钢结构的水性超薄型防火涂料,并从成膜聚合物的热稳定性和高温流变性方面研究了不同乳液对涂料阻燃性能的影响.模拟大板燃烧测试结果显示,醋叔防火涂料的膨胀倍率最高(为17.4倍),防火性能最好,燃烧30 min后钢板背温为304℃.热重分析表明,醋叔乳胶膜的热稳定性好,平均热降解速率最慢,使得其与聚磷酸铵的脱水成炭反应充分,生成的致密膨胀层能显著提高防火阻燃性能.动态流变测试结果表明:纯丙、苯丙熔体的储存模量(G')大于损耗模量(G″),以弹性流动为主,复合黏度大于1000Pa.s;醋叔熔体的G″大于G',以黏性流动为主,复合黏度为33 Pa.s,在低频区域表现出牛顿型流体特征,在高频区域末端,复合黏度稍有减小.以上结果表明,热稳定性好、复合黏度低的黏性流体更适合做防火涂料的成膜物质,有利于涂层的膨胀阻燃.In this investigation, the waterborne ultra-thin fire-retardant coatings for steel structures were prepared respectively with the silicone-acrylic, acrylic, styrene-acrylic and VAc-VeoVa latexes as the binder. Then, the effects of the binders on the fire-retardant performance of the coatings were discussed in terms of the thermal stability and the high-temperature rheology. The combustion test results of analoging large panels show that the expansion ratio, 17.4 times that of the fire-retardant coatings from the VAc-VeoVa latex, is the largest, and its fire-retardant performance is the best with a steel backside temperature of 304 ℃ after a 30-min combustion. It is seen from TGA curves that the VAc-VeoVa polymer is of good thermal stability and its average thermal degradation rate is the lowest, and that those characteristics of the VAc-VeoVa polymer provide enough time for its reaction with ammonium polyphosphate, thus generating a dense char layer which can remarkably improve the fire-retardant performance of the coating. Moreover, the results of the dynamic rhcological test demonstrate that, for the acrylic and styreneacrylic molten polymers, the storage modulus （G＇） are higher than the loss modulus （G＂）, which means that the elastic flow is predominant in these melts, and their complex viscosities are more than 1 000 Pa. s, while for the VAc-VeoVa molten polymer, G＂ is higher than G＇, which means that the viscous flow is predominant in this melt, and its complex viscosity is 33 Pa. s, and that, for the VAc-VeoVa melt, a Newtonian fluid property is displayed at the low frequency stage, and the complex viscosity slightly decreases at the end of the high frequency stage. The above-mentioned results show that the viscous fluid with good thermal stability and low complex viscosity can be used as the binder of fire-retardant coatings, which is helpful in the expansion and fire retardancy of the coatings.

关 键 词：水性超薄型防火涂料 成膜物质 动态流变性能 防火性能 

分 类 号：TQ630.1[化学工程—精细化工]