有机硅涂料(silicone coating)

有机硅涂料（silicone coating）
Research progress of organosilicon coatings
Silicone is the first widely used elements of the organic polymer compound, has excellent performances due to its unique chemical structure, widely used in various fields of national economy, but also plays an important role in the paint industry. Silicone coatings are organosilicon polymer and silicone modified polymer as main film coating material, it has excellent heat resistance, electrical insulation, corona resistance, radiation resistance, moisture resistance and weather resistance, stain resistance, monk water and chemical corrosion resistance and other properties, in recent years in the improvement and application performance of the products have been the rapid development of.
1 silicone resin coating made of organic silicon resin film material, mainly heat-resistant, weather resistant silicone anti-corrosion coating, scratch resistant transparent silicone coating, release and moisture-proof coatings and radiation resistant coatings and other varieties.
Coating with silicone resin with three methyl chlorosilane (CH3 SiCl3), two methyl two chloro silane [(CH3) 2SiCl2], three (C6H5SiCL3) phenyl chlorosilane, two phenyl chlorosilane two [(C6H5) 2SiCl2] and methyl phenyl chlorosilane CHO two (C6H5) SiCl2 as raw materials for hydrolysis polycondensation prepared. The effect of monomer structure, number and proportion of functional groups on properties of coatings is very important. The types of organic groups connected on silicon atoms also affect the properties of resins. Different
organic groups can make organosilicon resins exhibit different properties. For example, when the organic group is methyl silicone resin, with thermal stability, releasability, hydrophobicity and arc resistance; for phenyl, given the oxidation stability of silicone resin, crystalline polymer can be destroyed in a certain range;
As the vinyl group, the curing property of organosilicon resin can be improved, and coupling property is brought into being; when phenyl ethyl is used, the compatibility of organosilicon resin and organic substance can be improved. The base can be introduced in the siloxane backbone, increase its compatibility with alkyd resin and polyester resin; introducing phenylene and two phenyl ether subunit, biphenyl subunit of aromatic subunit and silicon carbon boron polymers, radiation resistance, the temperature can reach 300 to 500 DEG C; the backbone structure for the Si-N bond is silicone polymer, its thermal stability at 400 deg. In practical application, different organosilicon monomers can be selected according to the requirements, and different organic groups are induced in the organosilicon resin.
Chenguang Research Institute of chemical industry with a viscosity of 20 ~ s, 40mPa - hydroxy silicone oil (CH3) and 2SiCl2 methyl triethoxysilane as raw material, control of nR / NSI is 1.3 ~ 1.4, the quality of 2SiCl2 (CH3) and hydroxyl silicone oil ratio was 7O:3O, and the drop of water way at the temperature of 50 1H hydrolysis. Get the methyl silicone resin has good hardness and elasticity, can be used for flame retardant coatings were prepared by metal film resistors. Chinese Academy of sciences so CH3SiCl3 as the main raw material,
acetone and xylene as the solvent, soluble trapezoid with narrow molar mass distribution of poly methyl silicone resin was synthesized by the high temperature coating resin with a certain amount of aluminum powder, RTV silicone rubber prepared by 250 DEG C, old 1000 h, its flexibility, oil resistance and resistance have good corrosion resistance. HeFei University of Technology siloxane silicate four functional groups with three functional groups, through strict control of total hydrolysis reaction, the base material is prepared with silicate and silicone polymer properties, the binder and filler and other auxiliary materials according to a certain proportion of organic silicon heat-resisting coating made of.
2 modified silicone resin coating while the silicone resin has many excellent properties, but also has some problems: the general need for high temperature (150 ~ 200 DEG C) curing, curing time, the construction of large area is not convenient; adhesion to the substrate, organic solvent resistance, high temperature mechanical strength of the film is not good, the price more expensive etc.. In order to overcome these shortcomings, organic silicone resin was used to modify the organic resin. Modified silicone resin usually has the advantages of two resins, which can make up for some deficiencies in the performance of the two resins, thereby improving performance and expanding application fields. There are two kinds of modification methods, physical mixing and chemical modification. The effect of chemical modification is better than that of physical blending. Chemical modification is mainly on the end or side chain of polysiloxane chain, and then react with other polymers to produce block, graft or interpenetrating polymer networks, thus obtaining new
properties. In the coatings industry, silicone modified organic resins are mainly alkyd resins. Acrylic resin, epoxy resin, etc..
2.1 silicone modified alkyd resin coating
Silicone modified alkyd resin coatings is not only an alkyd resin paint film curing at room temperature and physical and mechanical properties, and has the advantages of good heat resistant silicone resin, UV aging resistance and good water resistance characteristics, coating is an excellent comprehensive performance. The first modification was to add the silicone resin directly to the alkyd reaction kettle that reached the end point,
The weatherability of alkyd resin is improved greatly. Another modification is to prepare reactive organosilicon oligomers to react with free hydroxyl groups on alkyd resins, and also to use organosilicon oligomers as polyols and alkyd resins for polycondensation. The alkyd resin modified by chemical reaction has better weatherability. Hunan University prepared by alcoholysis hydroxyl alkyd prepolymer and end to hydrolysis or different functional silicone prepolymer prepared by polycondensation reaction synthesis (A B) silicone alkyd type n block copolymer, and the copolymer as base material made of varnish; comprehensive performance of the varnish excellent, not only has the alkyd resin varnish film flexibility, room temperature curing, impact strength and advantages of good adhesion, but also greatly improve the heat resistance, ageing resistance and anti corrosion properties of water medium.
2.2 silicone modified acrylic resin coating
Silicone modified acrylic resin coating has excellent weatherability. It has the advantages of light retention, color retention, easy powdering and good gloss. It is widely used for pre coating of metal sheets, painting of machine equipment and weatherproof decoration and decoration of interior and exterior walls of buildings. Silicone modified acrylic resin has two types, solvent and emulsion, of which silicone acrylic latex coating has excellent weatherability, stain resistance, chemical resistance, is an environmentally friendly green paint. Hubei University uses a water-soluble radical initiator, with hydrogen containing silicone oil and butyl acrylate as raw material, the excellent performance of silicone / acrylic emulsion was synthesized by emulsion polymerization method; the emulsion has good acid and alkali. High and low temperature resistance and electrolyte stability, the coatings prepared with it have good weatherability and stain resistance. Ji'nan Chemical Research of acrylate monomer and D4 and vinyl seven methyl siloxane ring four as raw material, by adding a certain amount of grafting agent, using a batch of polyacrylate stable synthesis of polysiloxane emulsion. Sichuan Province Building Materials Industry Research Institute by pre emulsification process, the activity of silicone and acrylate monomer by emulsion copolymerization by organosilicon modified acrylic emulsion coating prepared with the emulsion of stain resistance, excellent comprehensive performance.
Fudan University with vinyl silicone monomer and acrylate, methyl acrylate and acrylic acid hydroxy ester monomer polymerization by seed emulsion was stable with excellent
properties of silicone modified acrylate emulsion. Acrylic silicone resin was modified by organosilicon monomer in Zhejiang University, and silicone acrylic emulsion coating was prepared. Polysiloxane polyacrylate interpenetrating network coating synthesis of Chongqing University, the coating is colorless and transparent, high hardness, strong adhesion, acid deposition, heat aging and has good permeability, can be used as anti weathering materials of rock friction moment.
HH silicone acrylic resin developed by Shanghai Academy of building research is suitable for the preparation of weather resistant coatings with high weatherability for more than 15 years. HeFei University of Technology with TEOS hydrolysis condensation part to polysiloxane with hydroxyl acrylic resin was prepared by organic silicone modified acrylic resin; the resin in acid and alkali resistance, salt resistance, solvent resistance and impact strength has significantly improved compared with that of pure polysiloxane, and high temperature resistance is obviously improved acrylic resin. Jiangsu architectural materials research and Design Institute introduced a certain amount of organosilicon functional group in the synthesis of acrylic resin, and prepared the solvent modified silicone resin coating with high weatherability. The Chinese Academy of Sciences of Lanzhou Institute of Chemical Physics with hydroxyl terminated poly two methyl siloxane, in two under the action of azo isobutyronitrile, and methacrylic acid (ester) monomers by solution copolymerization, silicon rubber modified acrylic resin, the resin has good heat resistance.
2.3 silicone modified epoxy resin coating
The modification of epoxy resin with organosilicon can not only reduce the internal stress of epoxy resin, but also increase the toughness of epoxy resin and improve its heat resistance. The poly (two siloxane) modified novolac epoxy resin has greatly reduced the internal stress and improved the cracking resistance index of the Institute of chemistry of Chinese Academy of sciences. Wuhan Research Institute of materials protection and the compatibility with epoxy resin and reactive silicone oligomer polycondensation of the prepared silicone modified epoxy resin has advantages of both epoxy resin and silicone resin, not only improve the heat resistance, but also has good corrosion resistance. Two point four
Modification of styrene acrylate emulsion with organosilicon modified styrene acrylic emulsion coating can obviously improve its weatherability, gloss, elasticity and durability. Shanghai University of Engineering Science by graft copolymerization of synthetic silicone modified styrene acrylic emulsion has the excellent properties of silicone and acrylic resin coating, good elasticity, the elongation was significantly higher than that of styrene acrylic emulsion coating. Silicone modified styrene acrylate emulsion building coating was prepared by adding a certain amount of organic silicone to styrene acrylic emulsion polymerization in Shanghai traffic science and technology university,
The coating has good water resistance, scouring resistance and durability.
2.5 silicone modified other resin coating
Silicone modified polyurethane coatings are widely used in Aircraft Skins, large tank surfaces, building roofs and cultural relics protection. The Chinese Academy of Sciences of Lanzhou Institute of Chemical Physics with hydroxyl terminated poly two methyl siloxane and alcohol solution of castor oil modified polyurethane prepolymer was modified, the curing rate of the blend is improved after the film adhesion, hardness, heat resistance is also improved. It also uses organosilicon modified urushiol resin as base material to prepare paint with resistance to boiling water and water vapor permeability. It can be used for corrosion protection of equipment for a long time. Shanghai Research Institute of building science by using epoxy resin, acrylic resin, silicone resin copolymer in the main chain introduced special hydrophilic functional groups made of water soluble epoxy silicone acrylic resin, the resin has excellent physical and mechanical properties, and has good resistance to aging. Anti ultraviolet and anti-corrosion properties. The coatings made of this resin are basically non-toxic, easy to construct, good in coating properties and good in decorative effect. In the research of Chenguang Chemical Research Institute, copolymerization of styrene, methyl methacrylate, acrylonitrile and organosilicon was used to develop a kind of impregnating agent for electronic devices.
3 silicone rigid wear-resistant coating
Study of organosilicon hard coating on silica sol as Q chain components, functional silicon or carbon functional silane to alkyl chain as a T component, in the presence of water, alcohol and acid catalyst by hydrolysis and polycondensation are part
of TQ type silicon resin pre silicon containing hydroxyl polymer solution. By adjusting the variety of RSi (OR ') 3 and the ratio of silica sol to the additive, the variety and solvent of the additive, we can make a kind of hard and wear-resistant coating with various properties. The viscosity of organosilicon coating is usually 4~25 m, Pa, s, and the solid content is 20% ~ 30%. After coating on the surface of the substrate, the remaining silicon hydroxyl groups are condensed under heating condition to form a network structure of hardened wear-resistant layer.
Silicone reinforced wear-resistant coating is superior to UV curing acrylic resin hardening coating in both wear resistance and weather resistance. Transparent plastics processed by organosilicon stiffening coatings have been widely used as glasses, car lampshades, instrument scales, compact discs and special architectural windows.
4 Conclusion
With the further research, development and improvement of new materials, the performance of silicone coating will be more excellent to meet the different needs of different industries or fields. With the improvement of people's life and beautify the demands for living rooms and buildings, silicone coating with excellent weatherability and stain resistant performance in the decoration of building has a broad application prospect; and, with the increasing awareness of environmental protection silicone coatings towards non pollution, green environmental protection development direction.
Refractory paint TK-000
Product ingredients: refractory paint TK-000 series by silicone resin as the main raw material, the product features: high temperature of 800 DEG, acid and alkali resistance, good blackness, high hardness, good weatherability. Application: metal, iron surface coating. For example the fireplace. Through the international quality standard: SGS non-toxic inspection standard. Viscosity: 65 + 5KU/30 C color the following 2 points: black, light adjustable hardness: H-2H dry conditions: 150 DEG C * 30 'solid content: 54% + 2% adhesion: 100% (iron) leveling: good feeling: good complementary series: silicone special solvent construction method: spraying standard packing: canned note: as the climate is different, that day water should be used in different products, more details please contact the company or the dealer.
According to the characteristics of low surface energy and low viscosity of organosilicon polymer itself, it is more suitable for practical application and modified in preparation process. The range of application of modified silicone resin is wider and better, which has been proved by the development trend.
The above is from the coating process. Chemical industry press. ISBN7-5025-1434-1/TQ.786) part of the third chapter silicone coating: if you can borrow this book, it might be of greater help to you;
Preparation of silicone resin, usually more than two or more than two units for hydrolysis, raw materials in the following article is given. When the hydrolysis conditions are different,
the composition of the intermediate product and the amount of the ring formation of the hydrolysis product are often greatly different, even though the formula is the same. Effects of various factors on hydrolysis:
1. Influence of pH value of hydrolysis medium
(1) acid medium; (2) neutral medium; (3) alkaline medium;
2. The influence of water content in hydrolysis medium: the amount of water needed for reaction is lower than that of silane reaction, which forms the gradual hydrolysis and polycondensation reaction, limiting the formation of ring. The hydrolysis of excess water is the opposite.
3, the influence of the solvent in the hydrolysis medium
4 、 the influence of equipment agitation speed in hydrolysis
5, the influence of temperature on hydrolysis, the higher temperature when hydrolysis, the molecular movement of components is intense, the chance of collision with each other is increased, which is beneficial to the growth of CO polycondensation, low temperature,
Otherwise.
Formulation formulation related factors: depending on the resin type, this factor varies:
(1) the average degree of substitution of alkyl hydrocarbons
(D.S.); (2) the average mass of% (including SiOx, phenyl, methyl); after a lot of chemists' careful research experience, there is a data range;
Modified resin: it has the advantage of two kinds of resin, and makes up for the disadvantage of silicone resin, and makes it more suitable for coating application. General organic silicone modified organic resin: alkyd resin, polyester resin, epoxy resin, acrylic resin, polyurethane resin, phenolic resin and so on;
Two methods of modification: cold spelling (physical method); chemical method;。