Kinetic Study Of Cycloaliphatic Epoxy Methylacrylate And Benzobioxole

Photoinduced polymerization reaction is the curing process which rapidly converts reactive liquid monomer into a solid polymer. Because of the fast curing speed, solvent-free formulation and low energy consumption, the photocuring technique is widely used in printing industry, inks, coatings, adhesives, biomedical materials, and so on.Prepolymer plays a key role in the formulations. The chemical structure of prepolymer has great influence on the physical and mechanical properties of the cured films. Bisphenonal A epoxy were the most commonly used resins. However, most aromatic compounds were inherently susceptible to UV absorption and subsequent degradation. The UV region of sunlight ranges from 290nm to 400 nm. The photooxidation of radiation at these wavelengths caused chemical and physical changes in polymers. In this paper, one cycloaliphatic dimethylacrylate (EPCDMA) was prepared. The kinetics and mechanical properties were performed. The results indicated that EPCDMA/TEGDMA (70/30 wt%) showed higher storage modulus than conventional aromatic dimethacrylate system BisGMA/TEGDMA (70/30 wt%) under the same curing condition.Because the majority monomer can not have the effective initiation activeness, although the photoinitiator is very few, it becomes the essential component in the formulation. As we know, the free radical photoinitiators are widespread applied. Because of the unusual smell of the photolysis products of the photoinitior such as Darocur 1173,Irgacure 184, in certain special situations, the unusual smell has already limited the application of this kind of photoinitiator. Diphenyl ketone is the cost lower kind of photoinitiator, but it needs the active amine as the co-initiator. The use of massive tertiary amine can cause the significant yellow stain of the film. Therefore, it's very significant to seek one photoinitiator with living compatibility.BDO widely exists to the naturally edible plant such as sesame seed and pepper. It is lower toxicity. In this article BDO as photoinitiator, the photopolymerization kinetics of acrylate is inverstigated. The results indicate that the BDO could initiate the photopolymerization of acrylate. The light intensity, the concentration of BDO and the structure of monomer have the significant effect on the activeness of the initiation system.In addition, in the BDO molecular, there are reactive hydrogens which may withdraw between two oxygenatoms. So the BDO as coinitiator may substitute the tertiary amines to use in the typeâ…¡photoinitiator system. When the BDO is used as coinitiator for BP and its derivatives, the final conversion of double bond may achieve above 80% in HDDA photopolymerization system of 2wt% BDO and 2wt% BP. The structure of BP and its derivatives have significant influence on this photoinitiator system.