Life Predictions of Elastomers in Drinking Water Distribution Systems
Life Predictions of Elastomers in Drinking Water Distribution Systems
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饮用水分配系统中弹性体的寿命预测
DOI：
10.1002/j.1551-8833.2007.tb08113.x
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发表时间：
2007
期刊：
影响因子：
--
通讯作者：
Raja M. Nagisetty
中科院分区：
文献类型：
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作者：
T. Rockaway;G. Willing;Raja M. Nagisetty
由于与三卤甲烷等消毒副产物的形成相关的健康问题日益严重，许多自来水公司已用氯胺代替氯消毒剂。在这一变化之后，一些公用事业公司报告了弹性体故障率大幅提高的问题。为了预测常见弹性体的长期性能，在三种温度（23、45 和 70°C）和三种浓度（1、30 和 60 mg/L）的组合下对天然橡胶进行了加速老化测试；氯丁橡胶；三元乙丙橡胶单体，过氧化物固化 (EPDM[P])；丁苯橡胶（SBR）；三元乙丙橡胶单体，硫磺硫化 (EPDM[S])；和丁腈橡胶。弹性体降解的特征是质量变化、体积变化、断裂应力、断裂应变和硬度。利用时间-温度叠加原理，将加速温度下的“短期”测试结果随时间推移来预测“长期”结果，生成不同消毒剂浓度在使用温度下的主降解曲线。相对而言，EPDM(P) 和 EPDM(S) 对氯胺降解最不敏感，其次是丁腈橡胶、SBR、天然橡胶和氯丁橡胶。
Because of increasing health concerns associated with the formation of disinfection by‐products such as trihalomethanes, many water utilities have replaced chlorine disinfectants with chloramines. Subsequent to this change, several utilities reported problems with substantially higher rates of elastomer failure. To predict the long‐term performance of commonly found elastomers, accelerated aging tests were conducted at combinations of three temperatures (23, 45, and 70°C) and three concentrations (1, 30, and 60 mg/L) for natural rubber; neoprene rubber; ethylene propylene diene monomer, peroxide‐cured (EPDM[P]); styrene butadiene rubber (SBR); ethylene propylene diene monomer, sulfur‐cured (EPDM[S]); and nitrile rubber. Elastomer degradation was characterized by mass change, volume change, breaking stress, breaking strain, and hardness. Using the time‐temperature superposition principle, “short‐term” test results at accelerated temperatures were shifted over time to predict “long‐term” results, generating master degradation curves at the service temperature for different disinfectant concentrations. Relatively, EPDM(P) and EPDM(S) were found to be least susceptible to chloramine degradation followed by nitrile rubber, SBR, natural rubber, and neoprene rubber.