The Basic Study Of Silicone-Acrylic Latex With High Performance

Based on the optimizing study on synthetic process of silicone-acrylate latex, different advanced technologies such as particle design, reactive latex particles blending, microemulsion polymerization, and nano-technology, were applied to prepare elastic silicone-acrylate latex, core-shell structured silicone-acrylate latex, respectively. Also, the application of these resulting silicone-acrylate lattices has been investigated.The basic processing parameters and production formula were determined based on the choices of organsilicone monomers including vinyl siloxanes and grafting siloxanes, and the effect of organsilicone content on polymerization process. The composition and properties such as particle morphology, particle size and its distribution of the obtained silicone-acrylate latex were characterized. The effect of organsilicone monomer content on the performances of resulting latex film was investigated, and the results show that the general performances of silicone-acrylate latex film are improved with increase of silicone content in monomers, and the latex film has excellent performance when the silicone content get to 8% of total monomers and the ration of MPTS to 203 silicone oil is 1:1.The elastic silicone-acrylate latex was prepared using two methods, i.e., reactive latex particles blending and direct copolymerization containing siloxane crosslinking agent. It's found that the resulting latex film has relatively good mechanical properties, water resistance and stain resistance when the weight ratio of reactive latex with epoxy group to normal silicone-acrylate latex is 6:4. Furthermore, the film formation process of blending latex was investigated. Siloxane crosslinking agent containing two- vinyl group (bi-(3-methacryloyloxyethyl) bimethylsilane, MEBS) was synthesized via condensation reaction between hydroxyl group and alkoxy of siloxane, and then the effect of MEBS on emulsion polymerization process was studied. The result reveled that polymerization rate reduces, whereas coagulum increases during polymerization process with the increase of MEBS content in monomers, and properties of exterior wall coatings based on direct copolymerization containing MEBS are similar with that of coatings resulted from blending method except thatAbstractwater resistance and hardness are better than that based on the latter when the content of MEBS attains 5%.Silicone-acrylate latex with core-shell structure was prepared by preemulsified monomer addition in a two-stage process, and also the detailed research about the effect of the ratio of core to shell part and Tg of the two parts on the properties of one pact wood coating was carried out. It's found that the latex film have higher hardness and better film-formation when the ratio of core to shell is about 6:4~8:2 and Tg of the shell part is at least 30 higher than that of core part. Two pact wood coatings were prepared through emulsion polymerization of acrylate, siloxane and acetoacetoxy ethyl methacrylate (AAEMA) in a seeded microemulsion polymerization-monomer swelling process, and the effect of seeded monomers, swelling monomers and crosslinking agent on latex film formation ability and properties have been emphasized. The result show that the two pact wood coating film have desirable glossiness and hardness when the mol ratio of AAEMA and hexamethylene diamine is about 1:4~ 1:2.Surface treatment of nano-SiC>2 can improve its dispersion stability in emulsifier aqueous solutions. The treated nano-SiCVsilicone-acrylate composite latex was prepared by in-situ emulsion polymerization, then the effect of nano-SiC>2 on polymerization process and stabilized mechanism of nano-particles hi composite latex were investigated. The experimental results indicated that the incorporation of nano-SiC>2 is helpful to improve the film properties such as mechanical properties, hardness, ultraviolet aging resistance, stain resistance and so on.Appropriate chmical oxidation of mumti-wall carbon nanotubes (MWCNTs) can introduce the reactive groups onto the surface of M...