دانلود رایگان مقاله انگلیسی آماده سازی یک آمین شاخه ای و مطالعات فیزیکی و حرارتی ترکیبات اپوکسی از جمله ترکیب آمین - وایلی 2018

ABSTRACT:

A branched amine, abbreviated as EATP, was synthesized by reacting ethylene diamine with methyl acrylate, followed by reaction with xylylene diamine via a two-step process. The prepared EATP (in the range of 5–30 parts per resin) was added to epoxy compositions with bisphenol A epoxy resin and a curing agent, xylylene diamine. The epoxy compositions were cured at high temperatures and processed for flexural strength testing and dynamic mechanical analysis. The results showed that the flexural strength was improved by 13% when 10% EATP was present in the epoxy matrix, but there was a decrease in tan d and storage modulus values. Moreover, the degree of fire hazard of the epoxy compositions and EATP was studied by measuring the heat release rate (HRR). The reduction in the HRR with higher amounts of EATP in the epoxy indicated that the xylylene groups of EATP enhance the thermal stability of the resin.

CONCLUSIONS

In this study, a branched amine modified with xylylene diamine was synthesized via a two-step reaction. The structures of the prepared products were analyzed with FTIR, 1 HNMR, and 13C-NMR. Furthermore, the final branched amine product was added to epoxy compositions and cured respectively for the tests of their physical properties and thermal heat resistance. As found by DSC, the activation energies of the epoxy compositions with EATP are in the range of 47.5– 49.6 kJ/mol. Moreover, the thermal degradation activation energies of the compositions were carried out with TGA. The results show that the thermal stability of the compositions increases until the amount of EATP is increased to 10%, but decreases as the amount of EATP added exceeds 10%. The compositions including 10% or less than 10% of EATP show an increase in flexural strength, while the glass-transition temperature (tan d obtained by DMA) decreases in proportion to the amount of EATP added. However, the HRR data confirmed that the flammability of the compositions decreased with increasing amounts of EATP.