Abstract: The anticorrosive performance of protective materials such as natural rubber, neoprene, high damping rubber used in damping bridge bearings and a new protective material named polyurea Qtech were investigated through tensile test and FT-IR. The tensile strength, elongation at break, hardness and molecular structure of the protective materials were analyzed after immersed in 5%H₂SO₄, 5%NaOH and 3. 5%NaCl for 30-90 days. The mechanical property results showed that polyurea Qtech gave the anticorrosive property similar with the other protective materials. The tensile strength was decreased by 13. 73%, 8.13% and 12.44%, and the elongation at break was decreased by 24. 49%, 11.01% and 10. 18% respectively after immersed in 5% H₂SO₄, 5% NaOH and 3. 5% NaCl respectively while the hardness changed a little. FT-IR showed that a small part of chemical bonds were broken but the internal molecular structure was changed hardly after ageing test.

Key words: bridge bearing, aging of rubber protection, pure polyurea

摘要： 通过拉伸试验和红外光谱研究了天然橡胶、氯丁橡胶、超高阻尼橡胶等桥梁支座防护用橡胶材料,以及喷涂型防护用纯聚脲材料(Qtech系列)的耐介质腐蚀性能,探讨了材料在5%H₂SO₄、5%NaOH和3.5%NaCl溶液中浸泡30~90 d后的拉伸强度、断裂伸长率和硬度等力学性能,以及分子内部结构的变化规律。力学性能研究结果表明,Qtech纯聚脲的耐介质腐蚀性能与橡胶材料相当,经5%H₂SO₄、5%NaOH和3.5%NaCl别下降了13.73%、8.13%和12.44%,断裂伸长率分别下降了24.49%、11.01%和10.18%,硬度变化幅度极小。红外微观结构研究结果表明,老化前后Qtech纯聚脲材料的表面化学键有小部分断裂,但分子内部结构变化不大。

关键词: 桥梁支座, 橡胶老化, 防护, 纯聚脲