Although epoxy resin has a certain waterproof function, it is not a conventional waterproof material and is not suitable for exterior wall waterproofing.
The classification of epoxy resins has not yet been unified. They are generally classified according to their strength, level of heat resistance and characteristics. There are 16 main varieties of epoxy resins, including general glue, structural glue, high temperature. strong glue and low temperature resistant glue. Glue, glue for water and wet surfaces, conductive glue, optical glue, spot welding glue, epoxy resin film, foam glue, constraint glue, bonding glue for soft materials, putty, special glue, latent hardening . glue, 16 types of adhesives for civil construction.
As an anti-corrosion material, epoxy resin not only has the characteristics of density, water resistance, good leak resistance and high strength, but also has good processability, such as strong adhesion, normal temperature operation and easy construction and moderate price.
Detailed information:
Epoxy resin is usually used with additives to achieve application value. Additives can be selected based on different uses. Commonly used additives include the following categories: curing agent, other;
The curing agent is an essential additive. Whether used as an adhesive, coating or castable, a curing agent must be added, otherwise the epoxy resin cannot cure.
Due to different application and performance requirements, there are also different requirements for resinsepoxy and additives such as curing agents, modifiers, fillers and thinners.
The reaction between the epoxy resin and the curing agent used is carried out by a direct addition reaction or a ring-opening polymerization reaction of the epoxy groups in the resin molecules, without release of water or other volatile substances. -products. Compared to unsaturated polyester resin and phenolic resin, they have very low shrinkage (less than 2%) during the curing process.
Baidu Encyclopedia-Epoxy resin
What are the functions of epoxy resin
The functions of epoxy resin: ①Epoxy coating Application Resin represents a significant proportion in coatings and can be transformed into varieties with different characteristics and uses. Their common characteristics: (1) Excellent chemical resistance, especially resistanceto alkalis. (2) The paint film has strong adhesion, especially to metal. (3) It has good heat resistance and good electrical insulation. (4) The paint film has good color retention.
Epoxy resin is a general term for a class of polymers containing more than two epoxy groups in the molecule. It is the condensation product of epichlorohydrin and bisphenol A or polyol. Due to the chemical activity of the epoxy group, a variety of active hydrogen-containing compounds can be used to open the ring, solidify and cross-link to form a network structure, so it is a resin thermosetting. Bisphenol ABisphenol A epoxy resin not only has the largest yield and the most complete varieties, but new modified varieties are also constantly increasing and the quality is constantly improving.
Several classifications
There are severalrs ways to classify epoxy resin adhesives in the industry:
1 According to their main components, they are divided into pure epoxy resin adhesives and modified epoxy resin adhesives
2. . According to their professional uses, they are divided into mechanical epoxy resin adhesives, construction epoxy resin adhesives, electronic epoxy resin adhesives and repair epoxy resin adhesives as well as circulation glue, glue for ships, etc. ;
< p>3. According to its construction conditions, it is divided into normal temperature curing glue, low temperature curing glue and other hardening glue;4 according to its packaging form, it can be divided into one. one-component glue, two-component glue and multi-component glue;
There are other classification methods, such as solvent-free glue, solvent-based glue and solvent-based glue. water,etc. However, component classification is widely used.
Applied to ①Coatings Epoxy resin accounts for a large proportion of applications in coatings, and it can be made into varieties with different characteristics and uses. Their common characteristics: (1) Excellent chemical resistance, especially resistance to alkali. (2) The paint film has strong adhesion, especially to metal. (3) It has good heat resistance and good electrical insulation. (4) The paint film has good color retention. However, bisphenol A type epoxy resin coatings have poor weather resistance. The paint film powders easily and loses its shine outdoors and is therefore not suitable for exterior cladding and highly decorative coatings. Therefore, epoxy resin coatings are mainly used as anti paintcorrosion, metal primer and insulating paint, but coatings based on heterocyclic and alicyclic epoxy resins can be used outdoors. ② In addition to poor adhesion to non-polar plastics such as polyolefins, epoxy resin also has good adhesion to various metal materials such as aluminum, steel, iron and copper; ; and thermosetting plastics. For example, phenolic, amine, unsaturated polyesters, etc. all have excellent bonding properties, which is why they are called universal glue. Epoxy adhesives are an important variety of structural adhesives.
③ Electronic and electrical materials have been widely used in the insulation and packaging of high and low voltage electrical appliances, motors and electronic components due to their many unique advantages such as high insulation performance, high structural strength andgood sealing performance of epoxy resin. The application is growing rapidly. Mainly used for: (1) Molding of electrical appliances and motor insulation packaging. Manufacturing of fully sealed integrated insulating enclosures for high and low voltage electrical devices such as electromagnets, contactor coils, transformers, dry transformers, etc. It has grown rapidly in the household appliance industry. From normal pressure pouring to vacuum pouring, it has developed to automatic pressure gel casting.
2) It is widely used for the insulation of devices equipped with electronic components and circuits. It has become an indispensable and important insulating material in the electronics industry. (3) Electronic grade epoxy molding compound is used for plastic packaging of semiconductor components. It has grown extremely rapidly in recents years. Due to its superior performance, it tends to replace traditional metal, ceramic and glass packaging. (4) Epoxy laminated plastics are widely used in electronics and electrical appliance fields. Among them, copper-plated epoxy laminate has developed particularly rapidly and become one of the core materials of the electronics industry. In addition, epoxy insulation coatings, insulation insulation adhesives and electrical adhesives are also widely used. ④Engineering plastics and composite materials Epoxy engineering plastics mainly include epoxy molding compounds and epoxy laminated plastics used for high-pressure molding, as well as epoxy foam plastics. Epoxy engineering plastics can also be considered as a generalized epoxy composite material. Epoxy composite materials mainly include fiberEpoxy glass (universal composite materials) and epoxy structural composite materials, such as pultruded epoxy profiles, winding hollow rotary products and high-performance composite materials. Epoxy composite material is an important structural and functional material in high-tech fields such as chemical industry, aviation, aerospace and military industry. ⑤Civil construction materials: mainly used as anti-corrosion floor coverings, epoxy mortar and concrete products, high-quality sidewalks and airport runways, quick repair materials, grouting materials for foundation reinforcement, construction adhesives and coatings, etc.