期刊
POLYMER TESTING
卷 70, 期 -, 页码 174-179出版社
ELSEVIER SCI LTD
DOI: 10.1016/j.polymertesting.2018.07.004
关键词
Poly(urethane urea); Castor oil; Isosorbide; Stress relaxation; Disulfide exchange reaction; Reprocessability
资金
- National Science Foundation of China [51703188]
- Basic and Frontier Research Project of Chongqing [cstc2017jcyjAX0426]
- Fundamental Research Funds for the Central Universities [XDJK2017A016, XDJK2017C022]
A bio-based poly (urethane urea) (CIPUU) network comprised of castor oil (CO), isosorbide (IS) and 4-aminophenyl disulfide (APD) was prepared and compared to the corresponding polyurethane (CIPU) consisting of CO and IS. Permanently cross-linked CIPU could not be reprocessed, while CIPUU could be reprocessed, as the network topology could rearrange through an associative disulfide exchange reaction. CIPUU had a higher Young's modulus than CIPU due to the higher rigidity of APD with benzene rings and the formed hydrogen bonding of the urea unit. Stress relaxation measurement indicated that the network topology of CIPUU was stable at temperatures lower than 100 degrees C due to the inactive disulfide exchange reaction at low temperatures. The exchange reaction became increasingly active with increasing temperature, as evidenced by the gradually reduced relaxation time. CIPUU showed excellent reprocessability, as indicated by the remaining gel fraction and fully recovered mechanical properties after thermal remoulding at 180 degrees C several times. In addition, CIPUU showed good thermal stability with an onset decomposition temperature (similar to 260 degrees C) much higher than the reprocessing temperature.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据