冷却塔氯磺化聚乙烯防潮涂料的湿热老化性能研究

Study on damp & head aging properties of CSPE moistureproof coating used in cooling tower

氮磷化聚乙烯（CSPE)涂料适于用作具有湿热老化作用环境的工业冷却塔塔身内壁的防潮涂层。在不同湿度的湿热空气、饱和空气和热水加速老化试验中发现随着试验的进行，涂层外观变坏，出现孔洞、裂缝等不均匀结构；附着力呈峰形曲线变化；吸水性不断提高，吸水率（Ｅ）出现明显的Ｌ形下降曲线，这些变化随温度增加而加剧。认为ＣＳＰＥ涂层属于“湿度（水分）促进老化类型”，这是由于在氧气较少的热水中热氧化反应产生的自由基较少，易因歧化反应而使高分子链断裂，生成极性基因，同时水解反应易于进行的老化机理所决定。热水老化是ＣＳＰＥ涂层最适宜的湿热老化试验方法。吸水性测试符合涂层的实用状况。可将试样块在汉水试验初期出现Ｌ形Ｅ－ｔｓ曲线确定为已达到老化临界状态，并可据此推算它的湿热老化使用寿命。

Chlorosulfonated polyethylene (CSPE) bang is ed as moistureproof layer of which niternal wall of industrial bang tower is Under damp & heat aging environment. It is found that the Properties of layer have changed with progression of experiment at damp & heat air of different humidity, saturation steam and hot water. These changes are accelerated with temperature. It is considered that mechanism of CSPE layer bang is the type that is anderated by water. Hot water aging is the bet way to test the Property of CSPE bang. The test of water absorption is alike to the situation in which coating is used in which coating is used in practice. E-ts curve of L shape of which appears at the beginning Of water soaking step is considered to achieve critical aging condition, and reckon aging life of the coating.