Synthesis And Properties Study Of A Novel Polycarbonate-based UV-curable Resin

Ultraviolet (UV) curing has many advantages, such as Energy saving, Environmental friendly and excellent performance of products. However, UV-curing coatings have distinct disadvantages such as thermal unstability, poor weather resistance and poor adhesion on specific substrate. Polycarbonate diols (PCDL) are raw materials for synthesis of novel polyurethanes based on polycarbonate diols, compare with the tradition PU, PU based on polycarbonate diols exhibit excellent mechanical properties like tensile strength, high thermal stability, excellent resistance to chemical and hydrolysis. Coatings containing polycarbonate-based UV-curable resin have excellent adhesion to PC substrate and ABS substrate. Furthemore, Fluorinated resin, which have many excellent properties, such as good chemical resistence, ageing resistence, stain resistence, are widely used in varous fields. Fluorinated polyurethane acrylate based on polycarbonate diols can combine some virtues of polycarbonate-based polyurethane and fluorinated resin. In this paper, a novel polycarbonate-based UV-curable resin (GMA-PCDL) was obtained by two-step reaction.Then the attention was put on the synthesis of fluorinated low surface energy polyurethane acrylate (FPUA). The application of GMA-PCDL and FPUA were also researched.1. A novel polycarbonate-based UV-curable resin (GMA-PCDL) was designed and synthesized in this section. The GMA-PCDL was synthesized by chemically attaching GMA on to an anhydride modified PCDL. The effects of inhibitor, catalyst, solvent and reaction temperature on the conversion and properties of GMA-PCDL were investigated. The structure of GMA-PCDL was characterized by FTIR, 1H-NMR and GPC. The coating films containing GMA-PCDL were prepared and applicated in surface protection of PC sheet. The properties of the films were discussed, the results show that the coating have a good adhesion, oil resistence and chemical resistence on PC sheet.2. Polycarbonate-based fluorinated low surface energy polyurethane acrylate (FPUA) was designed and synthesized in this section. FPUA was prepared from polycarbonate diols as a soft segment, IPDI as hard segment, DMBA as chain extender and monofunctional perfluorinated oligomer. The structure of resin was characterized by FTIR, 1H-NMR, GPC. The glass transition temperature (Tg) of FPUA were characterized by differential scanning calorimeter (DSC), the results show that the phase separation of FPUA was getting less with the increase in the content of fluorine attached on hard block. Thermogravimetric analysis (TGA) characterized the thermal stabilitie of FPUA films, the resulet showed the introducing fluorine into PU improves the thermal stability. The surface compositions of FPUA film at two different sampling depths were analysised by X-ray photoelectron sepectroscopy (XPS), the results showed the surface fluorine contents are significantly higher than bulk fluorine contents. The coating films containing FPUA were prepared and applicated in surface protection of PC sheet and the properties of the films were discussed, the results show that the introduction of fluorinated chain segments would not affected the application of PU.