| Unsaturated polyester resin (UPR) is a solution of polymer condensed by saturated di-alcohols and di-acids (including saturated and unsaturated di-acids) solved in active monomers (such as styrene). Being good in mechanical, electrical properties and chemical erosion resistance, it has been one important product among thermosetting resins. It has been widely used in many areas because of its good comprehensive properties and multiple shaping techniques. With the demand and consumption amount going up, the new types of resins with environmental protection and multifunction are expected to be studied and developed. The development will lead to decreasing shrinkage and viscosity, increasing surface quality and the function of processing and machinery.Three types of modified photo active unsaturated polyester resins were prepared in the dissertation. The conditions of synthesis, properties of UV-curing were investigated and it was found that the resins had some special properties such as very low shrinkage, low viscosity, lower surface energy, better thermostability and solvent resistance, et al. The main research content will be stated as follows:1. Unsaturated Polyester/ Polyepozy Resin Blocked copolymerResin Studies on the UV-curedThe UV-cured unsaturated polyester resins can't be used hi base environment due to un-reacted -COOH existed in polyester chains. In addition, it is difficult to get smooth film because of their high shrinkage during curing. To solve these problems, the UP-PER-UP blocked copolymer was prepared by the reaction of unsaturated polyester and polyepoxy resin under suitable conditions and recipes.The chains were extended while most of -COOH s were eliminated. The modified UV-curable resin was formed after the addition of the active monomers into the copolymer. The UV-cured process of the resin was investigated by means of FTIR spectrum and the properties of the UV-cured coat were characterized in terms of TG/DTA and other analysis. The surface hardness was tested by pencil hardness method and the base-resistance was known by means of soaking cured films in base solvent. The effects of photo initiator on properties of resins were studied. The results indicated that the UV-cured resin showed the advantages of both unsaturated polyester resin and polyepoxy resin. The base-resistant ability, thermostability and surface hardness of the resin were greatly improved. The volume shrinkage of the sample was lowed from 7% to 0.8%, which apparently smoothen the film. Accordingly, the adhesion to substrate became increased. It can also be used as one kind of none-shrinkage resins , thus the applications of UPR were widely developed.2. Research of UV-cured Gel-Coating ResinGel-coating resin is used to improve surface properties of products. In the paper, the UV-curable gel-coating unsaturated polyester resins were prepared by introducing m-phthalic acid instead of o-phthalic acid and the conditions of preparing has been studied. The UV-cure process of the resin has been investigated by using FTIR spectrum and the resin showed better UV-curing properties. Comparing with the resin containing o-phthalic acid by using the TG/DTA technique, the m-phthalic acid model UV-cured resin was obviously better than the resin containing o-phthalic acid in surface quality, thermostability, acid-resistant and base-resistant ability. In addition, comparing with curing method initiated by peroxide, UV-curing was more rapid, and UV-cured resin had better thermostability. The UV-cured gel-coating resin was characterized by saving energy, lessening air pollution, curing fast and being suitable toprocessing in automatic assembly line.3. Study on Unsatu rated Fluoro-Polyester ResinFluoro-resin has been widely used in plastics, rubber and coating, et al because of its properties of superior resistance to fouling, chemicals and excellent thermostability, mechanical and electrical properties. In the paper, the fluorocarbons were introduced into the unsaturated polyester chains by replaceing o-phthalic...
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