Accelerating Effects of N-Aryl-N ',N '-dialkyl Ureas on Epoxy-Dicyandiamide Curing System

作者：Liu Xiang Dong; Kimura Mika; Sudo Atsushi; Endo Takeshi^*

来源：Journal of Polymer Science Part A: Polymer Chemistry , 2010, 48(23): 5298-5305.

DOI：10.1002/pola.24329

• accelerator
• cure
• dicyandiamide
• epoxy resin
• N-aryl-N ',N '-disubstituted urea
• urea derivatives

This report focuses on epoxy-dicyandiamide (DICY) curing system accelerated by N-aryl-N',N'-dialkyl urea, aiming at clarifying the accelerating mechanism and the relationship between accelerating effect and molecular structure of the accelerators. Nine N-aryl-N',N'-dialkyl ureas were synthesized and investigated with measurements of differential scanning calorimetry, thermo gravimetric/differential thermal analysis and NMR spectroscopy. The results revealed that the ureas released the corresponding secondary amines by the thermal dissociation in the presence of epoxide, which led to the formation of tertiary amines that catalyze the addition reaction of DICY to epoxide. Moreover, a tendency that the ureas able to release more compact amines exhibited higher acceleration effects was discovered.

• 出版日期2010-12-1
• 单位浙江理工大学