文献类型：期刊文献

英文题名：A theoretical insight into the curing mechanism of phthalonitrile resins promoted by aromatic amines

作者：Chen, Zuowei[1];Wang, Liquan[1];Lin, Jiaping[1];Du, Lei[1]

机构：[1]East China Univ Sci & Technol, Sch Mat Sci & Engn, Shanghai Key Lab Adv Polymer Mat,Key Lab Ultrafin, Minist Educ,Frontiers Sci Ctr Materiobiol & Dynam, Shanghai 200237, Peoples R China

年份：2021

卷号：23

期号：32

起止页码：17300

外文期刊名：PHYSICAL CHEMISTRY CHEMICAL PHYSICS

收录：;EI(收录号：20213510826164);WOS:【SCI-EXPANDED(收录号:WOS:000680388700001)】；

基金：This work was supported by the National Natural Science Foundation of China (51833003, 21774032, 51621002, and 21975073).

语种：英文

外文关键词：Addition reactions - Aromatic compounds - Curing - Cyclization - Density functional theory - High temperature applications - Resins

摘要：High-temperature phthalonitrile resins have a wide range of applications, and understanding their curing mechanism is of great importance for academic research and engineering applications. However, the actual curing mechanism is still elusive. We presented a density functional theory study on the curing mechanism of phthalonitrile resins promoted by aromatic amines using phthalonitrile and aniline as the model compounds. We found that the rate-determining step is the initial nucleophilic addition of amines with nitrile groups on phthalonitrile to generate an amidine intermediate. The amines play a vital role in the H-transfer promoter throughout the curing reaction. The amidine and isoindoline are the critical intermediates, which can readily react with phthalonitrile through 6-membered transition states. The intramolecular cyclization of amidine intermediates is the vital step in forming isoindoline intermediates, which can be significantly promoted by amines. The proposed curing reaction pathways are kinetically more favorable than the previously reported ones, which can account for the formation of triazine, polyisoindoline, and phthalocyanine and provide a molecular-level understanding of the curing reaction.