单组分环氧胶固化剂及促进剂的改性研究

Modification of curing agent and accelerator for one component epoxy adhesive

采用间甲苯胺对固化剂双氰胺进行改性,红外表明双氰胺的—C≡N与间甲苯胺的—NH2发生反应,提高了固化剂的反应活性;XRD也证实了改性反应的进行。采用硫酸铜改性咪唑,XRD表明了有新的物质生成。经改性的双氰胺具有较好的活性和贮存稳定性。但单独使用改性双氰胺作固化剂,用量一般较大(为环氧树脂的25%),影响体系的流动性;而复合使用改性双氰胺和咪唑,在保证性能和固化时间的前提下,双氰胺的用量可减少至15%。改性双氰胺与环氧树脂具有较好的相容性,使环氧树脂固化体系的力学性能具有较大幅度的提高。

Dicyandiamide was modified by m-toluidine, FTIR spectrum showed the -C=N group of dicyandiamide had reacted with the -NH2 group of m-toluidine and the activity of curing agent was improved,XRD also proved the realization of reaction. Imidazole was modified by cupric sulfate, the new product was observed by XRD. Dicyandiamide has better activity and latent after modified, when it used alone, the amount of it is larger,which will worsen the liquidity of system. However, when dicyandiamide and imidazole were added together in epoxy adhesive, the amount of dicyandiamide decreased to 15%. The treated dicyandiamide have a better compatibility with epoxy adhesive, which contribute to improving the mechanical properties of curing epoxy adhesive greatly.