Research On The Synthesis And Separation Of Glycidyl Methacrylate

As an intermediate epoxy group,glycidyl methacrylate(GMA)is an important monomer in fine chemical industry.The carbon-carbon double bond and epoxy group in the structure of GMA make it usable in the fields of medicine,photosensitive materials,organic synthesis and polymer modification.In order to solve the problems such as harsh reaction conditions,inefficient or expensive catalyst and environmental pollution in the traditional preparation process of GMA,we study on the synthesis of GMA by esterification closed-loop method based on other researchers' previous studies.In this study,raw materials are MAA and ECH,and 1,1,3,3-tetramethylguanidine(TMG)is selected as catalyst from a bunch of amines due to its proton-donating nucleophilicity and facile access.All factors that may have an impact on the yield of GMA are explored.In addition,the catalytic mechanism of TMG is explained in detail.On the basis of single factor experiment,material ratio(MAA/ECH),reaction temperature and catalyst dosage are chose as independent variables in response surface methodology(RSM).According to the principle of Box-Behnken design and three-factor analysis method,the prediction model of quadratic polynomial regression equation is simulated through Design Expert to optimize the synthesis process of GMA.A valid quadratic model is used for predicting the response.The optimal conditions for yield obtained are: material ratio=1:2.26,reaction temperature=81°C,catalyst amount=1.4 wt%.Under this condition,yield of 3-chloro-2-hydroxypropyl methacrylate is 73.25% and yield of GMA is 63.17%.The observed responses highly agree with the predicted ones,and the Box-Behnken design is suitable for optimizing the synthesis of GMA.Furthermore,the continuous decompression distillation process is designed for the separate and refining of crude products obtained from GMA synthesis system.The optimal operation parameters of distillation column such as plate number,feed stage number,D/F and top tower pressure are obtained through simulation and optimization by Aspen plus software.The optimized process can effectively separate GMA,which is verified by experiment.At the same time,the result of experiment in small size shows that experimental values and simulated values are highly aligned with each other.Not only verified the reliability of the process simulation,but also have great significance to the industrial amplification of the separation system in the future.