Abstract: This article conducted the research on the properties of pure polyurea. The results showed that the tensile strength of pure polyurea could reach higher than 22 MPa, the elongation at break was over 4500 which was able to resist external damage. When polyurea coating was immersed in acid, alkali, salt and chlorine water for 60 d, the tensile strength decreased significantly, especially in acid and oxidizing medium by 27 .5% and 25. 5% respectively. When exposed in salt fog for 9 000 h, the tensile strength dropped by 4.4%, the elongation at break increased by 5. 0%. The FT-IR analysis showed that the polyurea molecule structure was less changed. The effect of salt fog aging was also not obvious. After ultraviolet accelerated aging test for 25 000 h, the tensile strength only decreased by 8. 6%, the elongation at break was not changed. It is suggested that polyurea has excellent weathering performance.

Key words: oil and gas pipelines, pure polyurea, anti-corrosion, aging resistance

摘要： 对纯聚脲的性能进行研究表明:纯聚脲的拉伸强度可达22 MPa以上,断裂伸长率可达450%以上,能够抵抗外力破坏;在酸碱盐等腐蚀介质中浸泡60 d,尤其以酸性和氧化性介质的腐蚀作用最强烈,拉伸强度明显降低,分别下降了27.5%和25.5%;经盐雾老化9 000 h,拉伸强度降低了4.4%,断裂伸长率增加了5.0%,FT-IR谱图分析显示,聚脲分子结构的变化幅度很小,盐雾老化对涂层影响不明显;紫外线加速老化25 000 h,拉伸强度只降低了8.6%,断裂伸长率基本不变,说明聚脲具有优异的耐老化性能。

关键词: 油气管道, 纯聚脲, 防腐蚀, 耐老化