Since The Synthesis And Properties Of Cross-linked Water-based Acrylic Resin

Acrylic resin have very good property to light and heat,and also with high chemical stability; while cross-linked acrylic resin have better resistence to water and solvent, etc; and to aquosity acrylic resin, it is friendly to environment and so the pollution can be decreased, it also can be used in electrophoretic coating. Cross-linked aquosity acrylic resin possesses all the advanteges resins show above, so its'market needs is very large and have high value-added. But now in the market most products used are abroad, products reserched and developed in our country have not been found. Thus, it is necessary to do reserch on self-crosslinking aquosity acrylic resin.Using propylene glycol monomethyl ether acetate, N,N-dimethyl formamide as solvent, and 2-(Dimethylamino)ethyl methacrylate(DMAEMA) and other monomers to proceeding radical solution polymerization; then acidified it. obtain the cation acrylic resin. Factors such as water solubility, molecular weight and glass transition temperature were selected to adjust the formula and technics. Analysis influence factor to resin's water solubility, discuss initiator, monomer concentration, feeding speed to film's property's effection. Results indicate the optimal condition is that using 2%wt azodiisobutyronitrile as iniator,15%wt DMAEMA, monomer's speeding time is 3h, keep the temperature at 85℃for 1.5h, under that condition the molecular weight of slef-crosslinking aquosity acrylic resin is 8433. coefficient of dispersion is 1.96.Tetrahydrofurfuryl methacrylate which have cyclic ether structure, is now widely used in cartilaginous tissue and dental restoration composite, it's also used to product adhesive. but is not seen in coating. Here we add it to make resin which will be used in paint, and discuss its effect to resin and film's property. Result indicate that 15%wt tetrahydrofurfuryl methacrylate can not only improve resin's adhesion and hardness.but also can improve its aquosity:the adhesion can rise from grade 1 to grade 0, and the pendulum hardness can rise from 0.691 was 0.739.Lead in isobornyl methacrylate(IBOMA) can reduce resin's viscosity which have caged scaffold structure, that can also synthesize high solid acrylic resin. Studies shows add little IBOMA during synthetic reaction can decrese resin's viscosity, but after IBOMA's weight surpass 5% wt keep add its weight the effect is not abvious. All in consideration,5%wt IBOMA is the suitable weight and can get 65% resin solid.Using FTIR. DSC. TG to study film's curing reaction temperature, reaction mechanism, glass transition temperature, etc. It was found that resin's glass transition temperature has been increased. of which the temperature before curing reaction is 50.3℃and 58.4℃after, when the curing reaction temperature is 156℃and react between hydroxy.In the reserch of electrodeposition process, parameter such as solid content, electrical voltage, electrodeposition time were analyzed, bath pH value and temperature, and flatting agent amount make great influence on film thickness and appearance. Results show coating have a good performance when the condition go as follows:film's solid content:15%wt, electrical voltage:120V, electrodeposition time:120s, bath pH value:5.86, bath temperature:28℃, flatting agent amount: 2%wt.