Silane coupled agent - the most promising silicone product

The general form of silane coupled agent can be expressed as: Y-R-SiX3 1, silane coupled agent classification X and Y are two types of active groups with different reaction characteristics. Among them, X easily and inorganic glass, clay, silicon dioxide, metal, metal oxides, etc. to produce a strong combination (chemical or physical), while Y is easy to produce a good combination (chemical or physical) with the resin, rubber, etc. in organic matter, precisely because of its There are two functional groups of pro-organic and pro-inorganic in the molecule, so that organic and inorganic materials, two materials with very different properties, can be firmly bonded together (evenly) through silane coupling agents for satisfactory bonding. This is where the name of the silane coupled agent comes from
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.According to the number of hydrolyzable groups (i.e. X-groups) connected to silicon atoms, silane coupled agents can be divided into three-d?ori and two-cell type two categories, in recent years, there have also been polymer-type silicone coupled agents with official energy groups as polymers. In foreign countries, because the production of silane coupled agent is mainly controlled by several large companies, in order to form a monopoly, each brand. Therefore, the same product, the market can appear several brands, a wide variety of names. At present, united carbide company (UCC) is the world's largest manufacturer of silane coupled agents, it also has the largest variety.silicone coupler - the most promising silicone product .jpg 2, the application of silane coupler silane coupler was first developed as a glass fiber treatment agent for fiberglass-reinforced plastics. Because the silane coupling agent improves the bonding between the glass fiber and the resin, the mechanical properties of the reinforced plastic are significantly improved. With the rapid development of composite materials, silane coupled agents are also developing rapidly in both varieties and yields. In recent years, the introduction of specific functional groups into certain materials by silane coupled agent can improve the surface properties of the material, obtain anti-static, mold-proof, anti-fouling, anticoagulant and physiological inertness, etc., and become the beginning of the new use of silane coupled agent. It is thanks to the development of many important applications that silane coupled agents have become an important branch of silicones.silane coupled agent is made of silicchloroform (HSiCl3) and unsaturated olefins with reactive groups, which are catalyzed by platinum chloric acid and then alcoholized. Silane coupled agent is essentially a class of silane with organic energy group, in its molecules at the same time with energy and inorganic materials (e.g. glass, silica sand, metals, etc.) chemical binding reaction group and chemical binding with organic material (synthetic resin, etc.) reaction group. Available in general Y (CH2) nSiX3, here, n-0-3; X-hydrolytic group; Y-organic power group, which reacts with resin. X is usually chlorine, methyl, ethyl, methyl acetyloxy, etc. , these groups hydrolysed to produce siol (Si(OH)3), and combined with inororated substances to form sioxane. Y is vinyl, ammonia, epoxy, methyl acrylamide,or phosphate. These reactions can be combined with organic matter reactions. In turn, by using silane coupled agents, a "molecular bridge" can be built between the interfaces of inorganic and organic matter, connecting two materials of a wide gap, thus improving the performance of composites and increasing bonding strength. This characteristic of silane coupled agent was first applied to fiberglass reinforced plastic (glass steel), as a surface treatment agent for fiberglass, so that the mechanical properties of glass steel, electrical properties and anti-aging properties have been greatly improved, the importance of the glass and steel industry has long been recognized.Currently, the use of silane coupled agents has expanded from fiberglass-reinforced plastics (FRPs) to fiberglass surface treatments for fiberglass-reinforced thermoplastics (FRTP), surface treatments for inormeric fillers, and sealers, resin concrete, water-crossed polyethylene, resin packaging materials, shell shapes, tires, tapes, coatings, adhesives, abrasive materials (grinding stones) and other surface treatments.in the two types of silane coupled agent performance of different groups, Y-group is the most important, it has a great impact on the performance of the product, to determine the performance of the joint agent. Only when the Y-group can react with the corresponding resin can the strength of the composite material be increased. It is generally required that the Y-group be compatible with the resin and be able to react evenly. Therefore, a certain resin has to choose a silane coupled agent containing the appropriate Y-group. When Y is non-reactive alkyl or aromatic, it does not work on polar resins, but can be used in non-polar resins, such as silicone rubber, polystyrene, etc. When Y contains reactive dyskin, pay attention to its reactivity and compatible with the resin used. When Y contains ammonia, is catalytic, can be used as a catalyst in the polymerization of phenolic, formaldehyde, melamine formaldehyde, can also be used as a curing agent of epoxy and polyurethane resin, at this time the conjugant is fully involved in the reaction, forming a new bond. Aminosilane-type coupled agents are generic and can act almost evenly with a variety of resins, with the exception of polyester resins. The type of x-group has no effect on the association effect. In this way, according to the type of reaction base in the Y-group, silane coupled agents are also known as vinyl silane, aminosilane, epoxysilane, -silane and methyl acrylamide silane, respectively, these organic energy group silane is the most commonly used silicone co-coupled agent.The application of silane coupling agent can be summed up in three aspects:(i) for the surface treatment of fiberglass, can improve the bonding properties of glass fiber and resin, greatly improve the strength of fiberglass reinforced composite materials, electrical, water, climate resistance and other properties, even in wet state, it is the mechanical properties of composite materials to improve, the effect is also very significant.At present, the use of silane concedants in fiberglass has been quite common, for this aspect of silane coupled agents accounted for about 50% of its total consumption, of which the more used varieties are vinyl silane, aminosilane, methyl acrylamide oxide and so on.(ii) for inorder fillers filled with plastic. Fillers can be surfaced in advance or added directly to the resin. It can improve the dispersion and adhesion of fillers in resins, improve process performance and improve the mechanical, electrical and climate resistance of filled plastics, including rubber.(iii) as sealants, adhesives and coatings, can improve their bonding strength, water resistance, climate resistance and other properties. Silane coupled agents often solve the long-standing problem of not bonding certain materials. Silane coupled agent as a adhesive works on the principle that it has two clumps of its own; one clump can bind to a viscous skeleton material; and the other group can bind to a polymeric material or adhesive to form a strong, high chemical bond at the bonding interface, greatly improving bonding strength. There are generally three methods for the application of silane coupled agents: one is as a surface treatment agent for skeleton materials, the other is to be added to adhesives, and the third is to be added directly to polymeric materials. From the point of view of giving full play to its efficiency and reducing costs, the first two methods are better. silane coupling agent in the adhesive industry has the following specific applications: (1) in the structural adhesive metal and non-metallic bonding, if the use of silane-like adhesive, can be combined with metal oxides, or with another silane alcohol, so that silicon atoms and the surface of the adhesive tight contact. If silane is added to butylphenol structure glue as an adhesive, the bonding strength can be significantly improved.(2) in the glue glass fiber at home and abroad has been widely used as a treatment agent. It reacts with the interface to increase the strength of the glue. For example, if the neolatin is not used as a treatment agent, the peeling strength of the glue is 1.07 kg/cm2, and if the aminosilane is used as the treatment agent, the peeling strength of the glue is 8.7 kg/cm2.(3) silane adhesive has a special function in the bonding of rubber with other materials. It significantly improves the glue strength of various rubbers and other materials. For example, when glass is connected with polyurethane rubber, the peeling strength of the glue is 0.224 kg/cm2 without silane as a treatment agent, and 7.26 kg/cm2 when silane is added.(4) the bonding problem that could not have been solved with a general adhesive can sometimes be solved with a silane coupled agent. Such as aluminum and polyethylene, silicone rubber and metal, silicone rubber and plex glass, can be based on the theory of chemical bonds, choose the corresponding silane coupled agent, to obtain a satisfactory solution. For example, vinyl tributylsilane (Y14310) can bond polyethylene to aluminum foil, and butene triethylene silane can make silicone rubber and metal tearing strength of 21.6 to 22.4 kg/cm2.with a general adhesive or resin can not only improve the adhesion strength, but also increase the water resistance and durability of the adhesion. For example, polyurethane and epoxy resins have a high adhesion to many materials, but the durability and water resistance of bonding is not ideal;other applications of silicone concedants include: (1) for the attachment of the fixation enzyme to the glass substrate surface, (2) sand protection in well drilling, and (3) To make the masonry surface water repugnent, (4) by anti-moisture, so that the fluorescent lamp coating has a higher surface resistance, (5) improves the moisture absorption performance of the organic relative glass surface in the liquid column. Silane coupled agent newly developed an important application is for the production of water cross-linked polyethylene, in recent years, in the domestic silicone emulsion treatment of wool textile experiments, found that the use of silicone coupled agent and silicone emulsion, can improve the performance of wool textile.
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