| Ultraviolet (UV) curing, with the advantages of Environmental friendly, Energy saving, Economic, Easy operation and Excellent finishing, is a green curing technology and widely used in inks, coatings, adhesives and other fields. Free radical curing system has advantages of fast curing, easily control, variety of resin and photoinitiator and also used widely. However, it has some disadvantages, such as high volume shrinkage and lack of adhension; while cationic curing system has lower volume shrinkage, excellent adhension, post-curing except lower reactivity. Hybrid UV curing system that combines the merits of free radical and cationic UV curing system has beening focused till nowdays. In this paper, the synthesis of free radical curing acrylic resin was studied firstly, then the attention was put on the synthesis of aliphatic acrylic epoxy resin, and the application of the resins was also researched.1. The carboxyl acrylate copolymer of poly (styrene-co-methyl methacrylate-co- methacrylic acid-co-buty acrylate) (PSMMB) was synthesized by using radical copolymerization. The effects of solvent types, azobisisobutyronitrile (AIBN) amounts, temperature and solvent amounts on the molecular weight and distribution of PSMMB were investigated. The structure of the product was characterized by using FTIR, and the glass transition temperature (Tg) of PSMMB was also investigated. The alkali-soluble acrylic photosensitive resin PSMMB-G was prepared by reaction of GMA and carboxyl group of PSMMB. With the increase of GMA, the alkali solubility of PSMMB-G decreases and the photosensitivity was enhanced. The property of PSMMB-G in photoresist system was also studied.2. The hydroxyl acrylate copolymer of poly (hydroxyethyl acrylate-co-methyl methacrylate-co-styrene-co-buty acrylate) (PHMSB) was synthesized and then alkali-soluble acrylic photosensitive resin PHMSB-T-G was prepared by the modification of TMA and GMA on copolymer PHMSB. The obtained resins were characterized by using FTIR, 1H-NMR, GPC, elemental analysis and DSC, and the property of PHMSB-T-G in photoresist system was studied. The results showed that: the resolution of the photoresist reached the level of 25μm, meeting the requirements of PCB applications.3. Alicyclic epoxy acrylic resin, which can be initiated by radical and cationic mechanism simultaneously, was synthesized by reaction of acrylic acid and alicyclic epoxy resin. The effects of catalyst types, amounts, reaction temperature, inhibitor and epoxy ring opening fraction on the reaction process were studied. The structure and rheological properties of the obtained resin were charactered by using FTIR, 1H-NMR and viscometer. The results showed that: alicyclic epoxy resin had the lowest viscosity among all the resins, with the degree of epoxy ring opening increasing, the viscosity of the resin increased; the result of the linear regression analysis between the viscosity and the temperature of the resins indicated that the flow activation energy of the resins increased with the increase of the degree of epoxy ring opening.4. The effects of initiator system composition, cationic initiator types, complex initiator concentration and post-curing time on the hybrid curing resin were investigated by determination the gel fraction during the curing process. The experiments showed that the complex initiated system of 432 and 1173 (weight ratio 1:1) with the mass fraction of 4% resulted in the highest gel content of the system after 24hrs'post-curing. The performance of the UV metal coating based on the hybrid curing resin was also discussed and the better formulation was determined.
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