聚氨酯防水涂料与PP-R管材接触相容性研究

Study on Contact Compatibility of Polyurethane Waterproofing Coating with PP-R Pipes

分别用聚氨酯防水涂料、二甲苯稀释的聚氨酯防水涂料包裹PP-R管材,于23℃、70℃恒温箱处理15 d后,进行热重、差示扫描量热分析以及拉伸性能测试。结果表明,常温下,聚氨酯防水涂料中有机小分子物质渗透进入PP-R管材的速度较慢,对管材的性能影响不明显;二甲苯稀释剂的加入以及温度的升高加剧了有机小分子物质向PP-R管材的渗透,使管材的抗氧性能和拉伸强度降低;建议工程应用中应避免二者直接接触。

PP-R pipes are covered by polyurethane waterproof coating and polyurethane waterproof coating thinned with xylene respectively and kept in thermostat for 15 days at the temperatures of 23℃and 70℃.Then,the thermogravimetry and differential scanning calorimetry of the pipes are carried out and their tensile strength are tested.Results show:at normal temperature,the small organic molecules in polyurethane waterproof coating infiltrate into the PP-R pipes slowly and have no significant impact on the pipe's performance;but the addition of xylene thinner and rising of temperature intensify the infiltration of small organic molecules into PP-R pipe and will undermine its antioxidant performance and tensile strength;so direct contact of the two materials should be avoided in engineering applications.