Optimization Of Addition Scheme Of PMMA Resin Synthesis Additive

Polymethyl methacrylate was prepared by free radical polymerization of methyl methacrylate.The polymerization process includes solution,suspension polymerization,bulk polymerization,etc.,and the polymerization equipment includes kettle,tube and tube in series.The polymerization process includes low temperature polymerization and high temperature polymerization.Among them,the high temperature continuous bulk polymerization method is more advanced,which solves the influence of "automatic acceleration" on the production of polymethyl methacrylate in the process of polymerization.In this paper,polymethyl methacrylate,commonly known as PMMA.,was produced on the basis of high temperature continuous bulk polymerization.In the process of preparing polymethyl methacrylate by high temperature continuous bulk polymerization,the polymer passes through the screw extruder,which leads to the degradation and depolymerization of PMMA due to high temperature and high shear.In addition,polymers are degraded and aged by oxygen,ozone and water in the air.In this paper,these two problems are solved: in the process of high temperature continuous bulk polymerization,light stabilizer is added in the polymerization process,thermal oxygen stabilizer is added in the extrusion process,or PMMA resin particles are mixed with heating oxygen stabilizer by screw extruder.The thermal oxygen stability of PMMA resin particles was improved by about 70 ?,and the UV absorption effect of PMMA resin particles between 300~400nm was better with the addition of light stabilizer.The experimental results showed that:1.Thermal oxygen stabilizer was 1010,1076,168,GS,0.1 to 1.0 wt%,main antioxidant and auxiliary antioxidant were combined,with a ratio of 3:1.2.The optical stabilizer is UV-234,5411,7401,7402,with a range of 0.1~1.0wt%,which can be used in combination.3.The addition method of hot oxygen stabilizer is as follows:solvent solution and extruder blending.4.The addition of light stabilizer was added by polymerization process,and it was found that the thermal stability of PMMA resin pellet decreased.5.The combination of thermal oxygen stabilizer and light stabilizer can effectively improve the thermal oxygen stability and light resistance of PMMA resin.