Synthesis And Application Of Water Soluble Photoinitiators Of α-Amino Propiophenone Derivatives

In this paper four watery UV photoinitiators were studied and synthesized through a four-step process. They were l-(4-aminophenyl)-2-piperidino-1-propanone dihydrochloride, 1 -(4-aminophenyl)-2-morpholino-1 -propanone dihydrochloride, 1 -(4-aminophenyl)-2-diethylamino-1 -propanone dihydrochloride, 1 -(4-aminophenyl) -2-burylamino-1-propanone dihydrochloride, which have not been reported in any literatures till now.As a key step of the synthesis, the Friedel-crafts acylation was researched. And the optimal operation variables were determined through orthogonal experiment: when 0.lmol acetanilide, 0.26mol aluminum chloride, 0.12mol propionyl chloride and 200ml carbon disulfide are introduced, and the reaction time is 5 hour, the yield can be up to 57.3%. The solid super acid catalyst was preliminary studied. Four solid super acid catalysts were prepared to take the place of aluminum chloride, and it was indicated that AlCl3 acidic resin can better catalyze the Friedel-Crafts reaction of acetanilide. The synthesis of l-(4-acetylaminophenyl)-2-bromo-1-propanone was discussed, and the mechanism and possible factors were analyzed. Hence the routine was determined, in which l-(4-acetylaminophenyl)- 1-propanone was reacted with Bromine dissolved in ethanol, so that the a -bromination can be carried on, resulted in the yield of up to 70.4%. Furthermore a waterborne acrylated epoxy prepolymer was also synthesized to prepare watery UV curing film, then the photoinitiability andproperties of the film were tested, and the relationship between the structure and properties of photoinitiators was investigated.The four products were tested by elementary analysis, Infrared spectrogram, Mass spectrogram, 1H nuclear magnetic resonance spectrogram and Ultraviolet spectrogram, etc. With the analysis and discussion of their photoini- liability, it was indicated that their max are all around 330 nm, and all of them have excellent solubility in water and good photoinitiability. Furthermore, the three Photoinitiators with α-tert-amine are obviously superior to the one with just α-sec-amine. Among the four photoinitiators l-(4-aminophenyl)-2-diethylamino-l- propanone dihydrochloride is the best and it has excellent use value.