水性聚氨酯防火缓蚀涂料中环烷酸咪唑啉衍生物含量对阻燃缓蚀性能的影响

Effect of Imidazoline Derivatives on Flame- Retarding Performance and Anticorrosion Behavior of Waterborne Polyurethane-Based Fire-Resistant and Corrosion Inhibition Coating

为了进一步提高水性聚氨酯涂料的阻燃抗蚀性能,以水性聚氨酯乳液为基料,聚磷酸铵(APP)、季戊四醇(PER)、三聚氰胺(MEL)、锐钛型二氧化钛(Ti O2)为阻燃体系,以环烷酸咪唑啉衍生物为缓蚀剂,配制成膨胀型防火缓蚀涂料。采用大板燃烧法、HTC-1热重分析仪对涂料的性能进行了表征;通过Hitachi-S4700扫描电镜(SEM)分析了涂炭层的微观结构;通过CS350电化学工作站测量了其极化曲线和电化学阻抗谱。结果表明,环烷酸咪唑啉衍生物的含量对水性聚氨酯防火缓蚀涂料的阻燃缓蚀性能影响显著:含有12.5%APP,3.8%PER,7.4%MEL,2.2%Ti O2,3.2%环烷酸咪唑啉衍生物时,涂料的耐燃时间可达到59 min,缓蚀效果较佳,原因是环烷酸咪唑啉衍生物通过与基料的良好混合,降低了基料对缓蚀剂的掩蔽作用,形成了一定的空间交联结构,提高了成炭强度和隔热能力,进而提升了涂料的阻燃缓蚀性能。

For the purpose of improving the flame-retarding performance and anticorrosion performance of waterbome polyurethane paint,waterborne polyurethane was adopted as the matrix,while ammonium polyphosphate(APP),pentaerythritol(PER),melamine(MEL) and titanium dioxide(TiO_2) were used as fire retardants and imidazoline derivatives as corrosion inhibition additives to fabricate expansiontype waterborne polyurethane flame- retarding and anticorrosion paint.The microstructure of as-prepared polyurethane paint/coating was observed with a scanning electron microscope,and its flame-retarding performance and smoke density were analyzed by thermogravimetric analysis and vertical burning test.Moreover,an electrochemical workstation was performed to measure the polarization curves and electrochemical impedance spectrum of the as-fabricated polyurethane paint.Results showed that imidazoline derivatives could significantly improve the fire resistance and anticorrosion performance of the as-fabricated polyurethane coating.Particularly,the paint consisting of 12.5%APP(mass fraction;the same hereafter),3.8%PER,7.4%MEL,2.2%TiO_2,and 3.2%imidazoline derivatives exhibited desired corrosion inhibition performance,and the fire resistance time of the coating was as much as 59 min.This was because imidazoline derivatives were well mixed with the polyurethane matrix thereby reducing the masking effect of the matrix towards the inhibitors.Namely,the corrosion inhibitors were able to form cross-linked structure with the polyurethane matrix and increase the strength and insulation capacity of the coating thereby improving the fire- retarding performance and anticorrosion behavior of the coating.