What is epoxy resin?

Question 1: What is epoxy resin? Simply put, it is chemical raw materials. . All polymer compounds containing epoxy groups in the molecular structure are collectively called epoxy resins. The cured epoxy resin has good physical and chemical properties, such as excellent adhesion strength to metal and nonmetal materials, good dielectric properties, small solidification shrinkage, good dimensional stability, high hardness, good flexibility and stability to alkali and most solvents. Therefore, it is widely used in various departments of national defense and national economy, such as casting, dipping, laminating materials, adhesives, coatings and so on.

Question 2: What is the purpose of epoxy resin? Epoxy resin is a thermosetting synthetic resin, which contains two or more reactive epoxy groups in its molecule, with aliphatic, alicyclic or aromatic carbon bonds as the skeleton. At present, bisphenol A(BPA) epoxy resin is widely produced and applied at home and abroad. According to the output and consumption, the proportion of various varieties in the world to the total epoxy resin is: bisphenol A epoxy resin 70-80% (about 95% in China), flame retardant brominated epoxy resin 12- 16%, phenolic epoxy resin 1-4%. The United States, Western Europe and Japan are the countries and regions that produce and consume the most epoxy resin in the world, followed by Chinese mainland, Taiwan Province Province and South Korea. In recent years, the average annual growth rate of epoxy resin in the world is 3.5-4%, while it is as high as 20-25% in China, which is not enough for production.

Judging from the relationship between the population and the consumption of epoxy resin in major countries and regions in the world, China has great development potential and broad prospects. At present, China has become the third largest consumer of epoxy resin in the world, second only to Japan. It is estimated that the domestic consumption of epoxy resin will exceed 6.5438+0.5 million tons in 20001year, while the output (middle and low grade) can only meet 50,000 tons, and 70,000-80,000 tons of high-purity or functional epoxy resin still need to be imported. China has become the most promising epoxy resin country in the world.

Automobile industry is the four pillar industries in China. From 20065438+0 to 2005, the high-quality epoxy resin needed for automobile electrophoretic paint was about 1 10,000 tons/year, and the epoxy resin needed for maintenance paint was also very considerable. The amount of epoxy resin in heavy-duty anticorrosive coatings for shipbuilding industry, marine industry and marine engineering will increase greatly. Insulation materials, castable materials for dry-type transformers, high-voltage switches, power transformers, large-scale high-voltage generators, high-voltage motors, and anti-corrosion of hydropower facilities in water conservancy and electric power industries all require a large number of electrical and electronic epoxy resins. The electronics industry and information industry need a large number of high-purity and ultra-high-purity electronic-grade epoxy resins, and the domestic demand for 200/kloc-0 will exceed 30,000 tons. In recent years, the container industry in China has developed rapidly, and has become a major container production base in the world. It is estimated that the demand for epoxy coatings for containers in 200 1 year will reach 40,000 tons, and about 2,500 tons of epoxy resin will be needed. Food-grade solid epoxy resin and water-soluble epoxy resin for food and beverage can coating have broad prospects. In 200 1 year, the output of epoxy resin coatings in China is expected to exceed 200,000 tons, including more than 60,000 tons of epoxy resin, 20,000 tons of epoxy resin adhesive, 6,543,800 tons of epoxy resin, 6,543,800 tons of epoxy reinforcing adhesive and 5,000 tons of epoxy resin.

In recent years, powder coatings and water-based coatings have become the mainstream and hot spot in the development of epoxy coatings. In China, the output of epoxy powder coatings in 1997 was 48,000 tons (including epoxy type accounting for 10- 15% and epoxy/ester type accounting for 75%), and 1999 reached about 70,000 tons, ranking fourth in the world, making it the largest powder coating producer in Asia. It is estimated that the demand in 20001year will reach about 85,000 tons, ranking third in the world, and it needs about 30,000 tons of special-grade epoxy resin for powder coatings. Waterborne epoxy resin coatings, including water-borne electrophoretic coatings, water-borne canned coatings and water-borne floor coatings, have been widely used in the United States, Japan, Western Europe, Taiwan Province Province, South Korea and other countries and regions, and China's economically developed areas such as East China and South China have just begun to try out. Many foreign businessmen are very optimistic about the waterborne epoxy coatings market in China. In China, powder coatings and water-based coatings have been identified as priority environmental protection coatings. It is estimated that in 200 1 year, the output of coatings in China will reach 2 million tons, of which water-based coatings account for 10%, powder coatings account for 5%, and * * * is about 2 10000 tons.

In the future, with the development of national economy, the domestic consumption of epoxy resin in powder coatings, electronics and electricians, civil buildings, composite materials and other fields will increase substantially. Therefore, it is necessary to increase the development of three new varieties of waterborne epoxy resin, outdoor anti-ultraviolet aging epoxy resin and flexible epoxy resin, so that domestic brand epoxy resin can occupy these emerging markets as soon as possible.

At present, on the eve of China's entry into WTO, famous foreign companies such as Shell, Dow, Ciba and Donghua Song have all entered the epoxy resin market in China. Dow plans to build a130,000-ton/year factory in Tianjin, a 30,000-ton/year epoxy resin factory in Guangdong and a 20,000-ton/year factory in Wuxi. China should establish its own multi-variety and multi-brand medium-sized semi-continuous devices according to its own national conditions.

Question 3: What are the advantages and disadvantages of epoxy resin? What is said upstairs is quite professional.

Question 4: What is epoxy resin B-stage epoxy resin curing is divided into three stages:

1, liquid operation time

Operating time (also called working time or service life) is a part of curing time. After mixing, the resin/curing agent mixture is still liquid, working and suitable for application. In order to ensure reliable bonding, all construction and positioning work should be done well within the curing operation time.

2, gel-into the curing

The mixture begins to enter the curing stage (also known as maturity), when it begins to gel or "mutate". At this time, the epoxy will not work for a long time and will lose its viscosity. We can't disturb at this stage. It will become a soft gel like hard rubber and can be pressed with your thumb.

Because the mixture is only partially cured at this time, the newly used epoxy resin can still be chemically linked with it, so the untreated surface can still be bonded or reacted. In any case, these abilities are declining for mixtures that are close to solidification.

3, curing-final curing

The epoxy resin mixture reaches the curing and solid stage, at which time it can be polished and molded. You can't press with your thumb at this time. At this time, the final reaction strength of epoxy resin is about 90%, so the fixing clip can be removed and left at room temperature for several days to continue curing.

At this time, the newly used epoxy resin can not be chemically bonded with it, and the epoxy surface must be properly pretreated, such as polishing, to obtain good bonding mechanical strength.

The epoxy resin B stage is also the second gel stage.

Question 5: What is the abbreviation of epoxy resin? The Chinese name of epoxy resin is epoxy resin, and the English name is epoxy resin.

CASNo.: 3889 1-59-7

According to the molecular structure, epoxy resins can be roughly divided into five categories:

1. glycidyl ether epoxy resin

2. glycidyl ester epoxy resin

3. glycidyl amine epoxy resin

4. Linear aliphatic epoxy resin

5. cycloaliphatic epoxy resin

The most common one is the first one, also called diphenol propane epoxy resin (abbreviated as bisphenol A epoxy resin).

Question 6: What is epoxy resin? At present, the classification of epoxy resin is not unified. Generally classified by strength, heat resistance grade and characteristics. The main varieties of epoxy resin are 16, including general adhesive, structural adhesive, temperature-resistant adhesive, low-temperature resistant adhesive, underwater adhesive, wet adhesive, conductive adhesive, optical adhesive, spot welding adhesive, epoxy resin film, foam adhesive, tensile adhesive and soft material adhesive.

There are several ways to classify epoxy adhesives in the industry:

1, which is divided into pure epoxy resin adhesive and modified epoxy resin adhesive according to its main components;

2. According to their professional uses, they are divided into epoxy adhesives for machinery, epoxy adhesives for buildings, epoxy adhesives for electronic eyes, epoxy adhesives for repair, adhesives for transportation, adhesives for ships, etc.

3. According to its construction conditions, it can be divided into normal temperature curing adhesive, low temperature curing adhesive and other curing adhesives;

4. According to its packaging form, it can be divided into one-component adhesive, two-component adhesive and multi-component adhesive.

There are other methods, such as solvent-free glue, solvent-based glue and water-based glue. But it is widely used in component classification.

Question 7: What color is opalescent epoxy resin? It should be normal if it is dry and transparent. It's impossible if you can't see what material you want to bond. If the general material does not require high glue strength, it is recommended that you use glue A. It will evaporate in a few minutes and become transparent! Strength is not bad! Ask me questions! I hope I can help you!

Question 8: What is the primary form of epoxy resin (bromine content is below 18% by weight)?

Question 9: What's the difference between epoxy resin gel coat and epoxy resin? Epoxy resin refers to a resin containing two or more epoxy groups.

If epoxy resin is used as gel coat, the initial viscosity should not be too large. Personally, I think E44 is not the best choice. If the viscosity is too high, it is difficult to ensure the surface quality of the curing agent. Considering the brittleness of E44, if there are no other components to toughen it, it may be more convenient to cure 593 with polyamide or 593.

Epoxy resin refers to a resin containing two or more epoxy groups. Up to now, in addition to all kinds of diphenol propane (bisphenol A) epoxy resins, the varieties of alicyclic epoxy resins are also increasing. This kind of epoxy resin not only has many varieties, but also has special properties, such as low viscosity, high strength, high elastic modulus, high elongation and high thermal stability. Therefore, it has been widely used in military and civilian fields. China started trial production of bad oxygen resin from 1958. The production of bad oxygen resin has spread all over the country, and the output has increased year by year. In terms of varieties, more than ten varieties of bisphenol A epoxy resin with different molecular weights have been put into production. Other bad oxygen resins with special properties, such as glycerol epoxy resin, organic titanium epoxy resin and alicyclic epoxy resin, have also been put into production [1].

Epoxy resin has the following advantages:

(1) Strong adhesion. Because the resin structure contains polar groups such as hydroxyl group and epoxy group, there is a large adsorption force between epoxy resin molecules and the surface of adjacent objects, so the adhesion in thermosetting resin is relatively high.

(2) The curing shrinkage is small. The curing shrinkage of epoxy resin is 1-6%, and that of polyester resin is 7- 10%. Therefore, the dimensional stability of the product is relatively high, and the creep performance is lower than that of polyester and phenolic resin.

(3) Good electrical insulation and chemical resistance.

(4) Epoxy resin is relatively stable and can be stored for a long time, with a general storage period of more than six months.

Its disadvantage is that (1) cost is higher than that of polyester resin.

(2) The viscosity is relatively high (referring to bisphenol A type), and it is not as convenient as unsaturated polyester resin when hand-pasting, so it is generally impossible to spray plastic. In order to improve the performance of epoxy resin, the relationship between the performance and structure of the resin was discussed. It is generally believed that the molecular backbone composed of C-C bonds has greater flexibility, higher elongation and lower thermal deformation temperature due to the weak intermolecular force. If oxygen atoms are introduced into the molecular skeleton, the softening point and hydrophilicity of the resin will be improved. If amide bond 10 NHCO+ is introduced into the molecular backbone, the softening point and rigidity of the resin can also be improved rapidly due to the generation of hydrogen bonds. Generally speaking, the softening point of the resin can also be improved by introducing aromatic rings or aliphatic rings into the molecular backbone. Increasing the number of active functional groups of epoxy resin can improve the crosslinking density after curing, which is beneficial to improve the mechanical properties and temperature resistance. However, this kind of resin often has high viscosity, which will bring difficulties to use and operation. In order to reduce the viscosity of epoxy resin and improve its temperature resistance, a new type of epoxy resin was synthesized from pentaerythritol and so on. This resin has a relatively low viscosity of 400- 1500 centipoise, is water-soluble and has a very low chlorine content (>:

Question 10: What color is the epoxy resin? This category is too big, and different varieties of epoxy resins have different colors.

Ordinary bisphenol A liquid epoxy resins, such as E44 and E5 1, have different colors. For example, the products produced by Changchun Chemical and Nanya Resin are colorless, transparent and viscous liquids, and the general chromaticity (platinum-cobalt alloy method) is less than or equal to 30. However, some domestic manufacturers, such as Jiangsu Sanmu and Shenzhen Tian Yu Chemical, produce a yellowish transparent viscous liquid. Solid bisphenol A epoxy resin is closed, such as E20 solid epoxy resin is yellow or brown transparent particles.

Liquid phenolic epoxy resins such as F5 1 and F44 are brown transparent viscous liquids.

There are other epoxy resins such as 7 1 1 epoxy resin and AG-80 epoxy resin, which are also brown epoxy resins.

In short, epoxy resins are colorless, transparent, slightly colored, light yellow, yellow and brown/brown, and the appearance of different varieties of epoxy resins is different. The appearance color of the same epoxy resin produced by different manufacturers will be different.