Research On The Synthesis Of Glycidyl Methacrylate

Glycidyl methacrylate (GMA) is an important vinyl monomer with epoxy group. It is a high active monomer which is widely used in coating,light-solidfied material ,adhensive ,medicine and so on..Using Hexamethylenetetramine as the catalyst and P-Hydroxyanisole as the inhibitor, glycidyl methacrylate (GMA) were prepared by two-step method successfully. It was not reported on the synthesis of Glycidyl methacrylate in articles till now.Several catalysts used in ring- opening reaction were filtrated systemicly. Quinoline ,1-methyl imidazole,pyridine,KOH+PEG400 and hexamethylenetetramine all had good activity.Hexamethylenetetramine was the better one.The influences of reaction parameters, such as raw material ratio, concentration of catalyst, reaction temperature, reaction time and concentration of inhibitor on the preparation of middle product were studied in 1st reaction, and the influences of reaction temperature , concentration of NaOH solution, reaction time and dosage of NaOH on glycidyl methacrylate(GMA) yields was also investigated in 2st reaction . GMA has been analyzed and characterized. The product qulity is better when the material volume ratio of ECH and MAA ranges from 1:1.05 to1:1.4. Product qulity decreases with the increase of the catalyst concentrations and the temperature of reaction ,but the yield of GMA rise.when the temperature of reaction is too low, The product qulity is better but the yield lower.The optimum reaction conditions are obtained by orthogonal exptl. design; ring-opening reaction:n(MAA):n(ECH) = 1:1.3, Hexamethylenetetramine catalyst 0.7%,reaction temp. is 80℃ , reaction time is 7 h, and concentration of inhibitor is 0.3%. ring-closing reaction : n(middle product):n(NaOH)=1:0.9, reaction temp. is 40℃, reaction time is 5 h. Under these conditions the yield of product can be reached 80.0 %.Study on single factor showed: n(MAA):n(ECH) < 1:1.4 ,concentration of catalyst >0.7%or reaction temperature higher than 90℃accelerated by-product reaction, product quality declined rapidly. Dosage of catalyst and reaction time increased, reaction accelerated, but it was not clear.GMA were investigated by Infrared Spectrum and Gas chromatogram-mass Spectrum.