Preparation And Properties Of Silicone Modified Styrene-acrylate Resin

Styrene-acrylate resin and its emulsion are important high-performance polymer colloidal materials with high added value.They are widely used in metal coatings,building materials coatings,adhesives and other fields with broad market prospects.With industrial upgrading and industry development,styrene-acrylate resin has defects in mechanical properties,weather resistance,corrosion resistance,water resistance and functionality.Silicone has good high temperature resistance,radiation resistance,oxidation resistance and other excellent properties,using silicone modified styrene-acrylate resin can effectively improve its temperature resistance,expansion,wear resistance and light retention,to achieve high performance of materials and expand the application of resin materials.In this paper,starting from improving the material properties of silicone-styrene-acrylate resin,two schemes of silicone-modified silicon-styrene-acrylate are proposed,as follows:1.The homogeneous mixture of Styrene?St?,isooctyl acrylate?2-EHA?,?-methacryloxypropyltrimethoxysilane?KH-570?,deionized water,Polyoxyethylene octyl phenol ether-10?OP-10?and sodium dodecyl sulfate?SDS?homogeneous mixture is silicone-styrene-acrylate pre-emulsion.Then,a light blue silicone propylene?SMI?latex was prepared by semi-continuous free radical emulsion polymerization under potassium persulfate?KPS?initiator system,and N-?-?aminoethyl?-?-aminopropylmethyldimethoxysilane?KH-602?as a crosslinking agent,silicone-styrene-acrylate?SMIN?resin was obtained by curing.The influence of the amounts of KH-570and KH-602 on the properties of SMI emulsion and SMIN resin were mainly investigated.The results showed that the conversion rate of SMI latex was above 88%after KH-570 modification,and the gel rate did not increase significantly.DLS and TEM analysis showed that the increase of KH-570 content led to the increased of particle size of SMI latex,and SM₅I latex had the best particle size distribution.FTIR showed that KH-570 and KH-602 were successfully copolymerized with St and 2-EHA monomers.XRD showed that the introduction of KH-570 and KH-602 reduced the crystallization ability of styrene-acrylate resin.TG analysis showed that KH-602 enhanced the thermal stability of SMIN resin.SEM and tensile tests showed that the increase in the amount of KH-602 caused the tensile strength and elongation at break of the SMIN resin to increase first and then decrease.The tensile strength of the SMIN₁₅ resin could reach 3.5 MPa and the stress repair efficiency of 47%.2.Light yellow silicon-styrene-acrylate?SSA?latex was prepared by 2-{[?dodecylsulfanyl?thiocarbonylsulfanyl]sulfanyl}propionic acid?DSCPA?,styrene?St?,isooctyl acrylate?2-EHA?,vinyltrimethoxysilane?VTMS?,polyoxyethylene octylphenol ether-10?OP-10?,sodium lauryl sulfate?SDS?and deionized water through mixing and semi-continuous RAFT emulsion polymerization.Further curing under vacuum and high temperature to obtain silicone-styrene-acrylate?SSA?resin.The effect of VTMS contents on the properties of SSA latex and resin were mainly studied.The results showed that the increase in VTMS content broadens the distribution of SSA latex particle size and increases the average particle size.FTIR analysis indicated that the silane coupling agent VTMS were successfully copolymerized with St and 2-EHA monomers.GPC indicated that the increase in molecular weight of SSA and the broadening of the molecular weight distribution are due to the increase in VTMS content.TG and DMA analysis showed that VTMS enhanced the thermal stability of SSA resin,and the glass transition temperature?Tg?increased from 35.1°C to 40.9°C.SEM and tensile tests showed when the VTMS content was 0 to 4wt%,the tensile strength of SSA resin increased from 3.6MPa to 5.8MPa,and the elongation at break first increased from405%to 680%and then decreased to 480%.The maximum strain repair efficiency of SSA-2 resin was 78%,and the maximum stress repair efficiency of SSA-4 resin was81%.Tests such as water resistance,scratch hardness,solvent resistance and corrosion resistance indicated that the water contact angle of SSA resin increased from 85°to 105°with the increasing of VTMS contents,and the scratch hardness,solvent resistance and corrosion resistance were enhanced.