Preparation And Performance Of UV-curing Pure Acrylic Fluorinated Polyurethane

UV-curing technique is concerned, because of the high efficiency, energy-saving,environmental protection and basic operation. Urethane-acrylate is widely used inmany fields, for the good physical properties and aging properties. Waterborne UVcurable coating combined the advantages of UV-curing technology and waterbornecoatings. Environmental pollution and damage of human body is greatly reduced.Study on the production of new UV-curing pure acrylic fluorinated polyurethane andwaterborne fluorinated polyurethane by HDI trimer, polyhydroxy fluorinated acrylateand hydroxyethyl. Curing behavior of colored paint and coating performance werestudied. As well as preparation process of water-soluble coating’ performance wasstudied. The main results were as follows:The pure acrylic UV-curing fluorinated polyurethane resin was prepared by HDItrimer, hydroxyethyl acrylate (HEA), polyhydroxy fluorinated acrylate. The resinswere characterized by Fourier transform infrared spectroscopy (FT-IR),1H nuclearmagnetic resonance (1HNMR) and Gel permeation chromatography (GPC). Theprocess of reaction was titrated with isocyanate. The suitable catalyst and reactiontemperature were studied. Cured varnish were tested the basic physical (pencilhardness, flexibility, adhesion and glossiness). The results indicated that：the expectedproduct was prepared successfully. The content of suitable catalyst is0.025%. Thefirst step appropriate reaction temperature is45℃; the second step is55℃.The storetime of products can be more than365days. The pencil hardness of coatings is H;flexibility is1mm; the level of adhesive force is0;gloss is between40°～60°.Pigments and fillers have been put in the stable urethane fluorined acrylate withsuitable ratio. The gray, red, yellow and black color paints were made. The initiator,active diluent, light source power, light source height and paint fineness, filmthickness on the influence of film cure were researched. Conversion of double bond isstudied for front and back of coatings.The performance of oil resistance, heatresistance and aging resistance were tested. However, the thermo-gravimetric of curedcoatings were tested. The results indicated that：suitable curing process for four colorpaints was that the gray and red paint used photoinitiator Ⅲ; the yellow usedphotoinitiator Ⅱ; the black used photoinitiator Ⅳ; the content was6%; the active diluents was10%HDDA and5%TMPTA mixed diluent; ultraviolet lamp height was15cm, lamp power for1000W; fineness of paint was20~45μm, thickness of paintfilm for30~40μm. Four color paint film of positive curing degree were all above72%. The conversion of double bond of gray, red, yellow and black coatings is descening.Bottom of coatings were worse. Coatings have good aging resistance, solventresistance and thermal stability.Polyurethane fluorined acrylates was modified. UV-curing water-bornepolyurethane fluorined acrylate was prepared. The resins were characterized byFourior-transformed infrared spectroscopy (FT-IR) and1H nuclear magneticresonance (1HNMR). The shear rate and preparation of emulsion time were studied.The size of the stable emulsion and distribution are tested, as well as the differentcontent of solid latex viscosity, the emulsion stability and freeze-thaw cycle. For thecured film thermogravimetric (TGA) test and basic performance test were conducted.The results showed that: the expected product was successful prepared. Theproportion of triethylamine and the rate of shear have great influence on particle size.When the rate of share increased, the particle size reduced. The emulsion that themole ratio of polyisocyanate and triethylamine are2:0.4and2:0.5the particle sizedistribution is narrow. The particle size is between2.5～5.0μm. With the ratio of-NCO and triethylamine increasing the viscosity is gradually reduced. Along with theincrease of the content of solid, viscosity increased significantly. After centrifugalsedimentation the particle size increased to8~13μm. Emulsion can store half a yearand can tolerate low temperature resistance. The emulsion is stable which the moleratio of-NCO and HEA are2:0.4and2:0.5, as well as good performance andthermal stability of cured coatings.