Synthesis And Research Of Organosilicon Modified Waterborne Acrylic Resin

The traditional solvent based coatings have caused many environmental problems because of the large pollution.People urgently need to study new low VOC discharge coatings.Water-based acrylic resin provides a better way to solve these problems.However,there are many defects in the acrylic resin itself,and it must be modified and organic at the same time.Silicon is a hot spot of research today.It has good high and low temperature properties,good hydrophobicity and crosslinking.The advantages of silicone modified water-based acrylic resin will give full play to the superior properties of the resin.The water based acrylic resin emulsion obtained by semi continuous seed emulsion polymerization process is milky white,the mechanical stability reaches 60 days,the particle size is 135.21 nm,the polydispersity index is 0.047,the contact angle is 77.14°,the heating is decomposed at 345.6 ?.The performance of the emulsion is best when the optimum dosage of the initiator is 0.4%,the active acrylic monomer is 5%,and the pH is 8.With the introduction of the vinyl siloxane KH151 and KH570 into the main chain of acrylic acid to get the modified resin,the water absorption of the resin decreased obviously,the contact angle increased by 8.16 and 13.51 degrees,the particle size increased to145.81 nm and 154.12 nm,the maximum decomposition temperature increased to 406.22 and424.25,respectively.The electrochemical analysis showed that KH570 had better corrosion resistance.It was determined that the addition of two substances had a lower gel rate at 6%and 5% respectively.KH550 and KH560 were introduced into the side chain of acrylic resin to get the modified resin.The particle size of the resin was around 147 nm,the maximum decomposition temperature of the contact angle was 80.64 and 82.47 degrees to 407.58 and403.59.The electrochemical analysis showed that the KH560 modified tree grease had better corrosion resistance.The dosage and dosage of siloxane were good at 0.3% and 4%respectively.With the introduction of vinyl terminated and hydroxy terminated polysiloxane into acrylic resin,the water absorption of the resin decreased to less than 8%,the contact angle increased to 117.19 and 108.91 degrees,the stability of mechanical and calcium ions decreased to 3 days and 2 days,the particle size increased to 174.99 nm and 179.22 nm,the fastest decomposition temperature rose to about 400 centigrade,and the electrochemicalanalysis showed that The resin has the best corrosion resistance,and the optimum dosage of two polysiloxanes is determined to be 5%.