Synthesis And Photocuring Properties Of Aliphatic Amine Co-Initiator With Different Chain Length

Recently, photocuring technology attracted a great deal of attention due to its many obvious advantages. Photoinitiator is an importants component in photocuring systems. Free radical photoinitiators can be divided into two types: cleaveage initiator and hydrogen abstraction initiator. Hydrogen abstraction initiators are utilized with tertiary amine compounds and these photoinitiator systems have good anti-oxygen inhibition. Most commercial tertiaryamines are low molecular weight molecules, low molecular weight aromatic amines are toxic and volatile. In order to overcome the disadvantages of low molecular weight photoinitiator, one effective approach is to synthesize polymerizable and high molecular weight amine coinitiators. A series of aliphatic amines coinitiators was synthesized via Michael Addition reaction and their various properties were investigated in this research.Aliphatic amines, (N, N-di (methoxycarbonylethyl) octylamine (DMOA) ,N, N-di (ethoxycarbonylethyl) octylamine (DEOA) ,N, N-di ( butoxycarbonylethyl ) octylamine ( DBOA ) , N , N-di(octoxycarbonylethyl)octylamine(DOOA)) ,with different chain length were synthesized via Michael Addition reaction of octylamine with methyl acrylate, ethyl acrylate, butyl acrylate and octyl actylate respectively , then characterized by Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. The photoreduction and fluorescence quenching results showed that the chain length of aliphatic amines had only slightly effect on the formation of Charge transfer complex , the charge transfer and proton abstraction between CQ triplet and amine. The Real Time Infrared results showed that photopolymerization rate had a slight decrease with the increase of chain length of aliphatic amine, and chain length had only minor effect on the double bond conversion of methyl (acrylate). Besides, the Real Time Infrared results indicated that with the increase of concentration of co-initiator amine, polymerization rate and double bond conversion increased in the range we studied and there was an optimum benzophenone concentration that had effect on photopolymerization rate . Photopolymerization rate and conversion decreased with the increase of monomer functionality.