The Preparation Of Mutil-functional Group Methacrylate Monomers Via Cyclic Addition Reaction And The Study Of Its Properties

In this paper,a series of monomers were synthesized by reacting of hydroxyl groups with anhydride groups to form carboxyl groups and reacting of carboxyl groups with epoxy groups to form hydroxyl groups.The photopolymerization process of the same series of monomers and the properties of the cured materials were investigated,the differences between the different series of monomers were investigated by using different alcohols as raw materials.The ring-opening reaction of hydroxyethyl methacrylate(HEMA)with succinic anhydride was used to synthesize monomer A-1-1,then ring-opening reaction of monomer A-1-1 with glycidyl methacrylate(GMA)synthesizing a double-fuctionnal monomer A-1-2;respectively,reacting with succinic anhydride and GMA once in a single cycle for 5 cycles,obtaining 10 kinds of A series monomers.Each reacting with GMA once,the functionality of the monomer increased by one.The photopolymerization kinetics were studied by real-time infrared spectroscopy(RT-IR).The lower the functionality of the monomer,the higher the degree of polymerization.The degree of polymerization of the monomer with carboxyl groups is higher in the same functionality;With the increase of the photoinitiator 2-hydroxy-2-methy 1-1-phenyl-1-propanone(1173)concentration and light intensity,the polymerization rate of the monomer and the double bond conversion rate were significantly improved.Compared to the commercial trimeric monomer trimethylolpropane trimethacrylate(TMPTMA),the monomer A-2-2 was more reactive.The mechanical properties of the cured materials were studied by dynamic mechanical analysis(DMA).The storage modulus of the materials after curing was high,there were some differences between different functionalities and groups.Ethylene glycol and glycerol were used instead of HEMA,which were respectively reacted with succinic anhydride and GMA for three cycles and two cycles to synthesize hexafunctional the monomer B-3-2 and C-2-2.A comparative study was conducted with A-5-2,the difference between monomers prepared with different alcohols was selected.The photopolymerization kinetics was studied by real-time infrared spectroscopy.The polymerization degree of the monomer B-3-2 was the highest,the polymerization degree of the monomer A-5-2 was the lowest.The mechanical properties of the cured materials were studied by dynamic mechanical analysis.The storage modulus of the cured materials were high.The crosslink density of the monomer B-3-2 was the lowest,the crosslink density of the monomer A-5-2 was the highest.The viscosity and flow behavior of the monomers were investigated by a rotary viscometer.These monomers all exhibited shear thinning,the viscosity of the monomer B-3-2 was lower than that of the other two monomers.