What are the epoxy resin toughening agents, and which one is more reliable for epoxy resin toughenin

As a high-performance, high-value-added adhesive, epoxy resin adhesive is highly valued by the industry, but at the same time, counterfeit and shoddy products are often patronized. Therefore, we can identify it by the following chemical methods. Method 1:

The sample is dissolved in sulfuric acid, and then concentrated nitric acid is added, and a large amount of sodium hydroxide solution is poured into it. The second type: drop 5 drops of concentrated nitric acid on the resin adhesive film, move the reactant into the test tube after a few minutes, add 6ml of acetone and then add potassium hydroxide ethanol solution to make it alkaline, if it turns from red to purple, it indicates that it contains epoxy resin glue containing bisphenol A type, this method is also intuitive; Method 3:

Take the adhesive film or glue solution, p-phenylenediamine and 8ml of sample water, boil for 8min, if it is epoxy resin, the solution is peach....

The friend on the first floor said that it should belong to plasticizers, and toughening agents are generally epoxy and non-epoxy.

Epoxy form is divided into single epoxy form and double epoxy shape, the most common epoxy form is epoxidized cardanol, double epoxy form has polypropylene glycylene glycidyl ether, linoleic acid dimer diglycidyl ether, etc., non-epoxy toughener has polysulfide rubber, urethane prepolymer, modified polyether and so on.

Reactive liquid (RLP) nitrile butadiene rubber (BNR) is the most effective and reliable way to toughen epoxy resins, which can be verified from the use of similar products in military and aerospace products.

CHX100 end-epoxy reactive liquid nitrile rubber (ETBN) is a high-tech product with our company's own intellectual property rights, as an end-epoxy product, compared with other ETBN products at home and abroad, there are the following typical differences:

1 CHX100 is a product with 100% nitrile rubber content.

2. The viscosity of the product is low, and it can be used directly.

The 3 CHX100 is a P-free product.

CHX100 ETBN products can completely overcome the following shortcomings of traditional CTBN products:

Pre-polymerization is sometimes required in the use of CTBN products.

At the same time as the prepolymerization of CTBN products, it is inevitable that the curing reaction will occur, which will seriously affect the product performance.

CTBN products are not very effective for slightly low temperature and ambient curing types.

CTBN does not react sufficiently with epoxy, which affects the performance of the final product.

The CHX100 ETBN product is very easy to use. There is no need for prepolymerization, and the epoxy functional groups at both ends are directly opened during the curing process at high temperature, slightly low temperature and room temperature, which has the same reactivity as the epoxy main body and can be fully cured. During the curing process, the phase separates by itself, forming an "island" structure that is closely connected to the main phase.

At present, there are several ways to toughen epoxy resins: toughening and modification with second phases such as elastomers, thermoplastic resins or rigid particles; The thermoplastic resin is continuously worn through the thermosetting resin to form an interpenetrating network meter toughening modification; toughened by changing the chemical structure of the cross-linked network to improve the activity of the network chain molecules; Controlling the inhomogeneity of the cross-linking state of the molecule to form a heterogeneous structure that is conducive to plastic deformation to achieve toughening. In recent years, scholars at home and abroad have devoted themselves to the study of some new modification methods, such as blending heat-resistant thermoplastic engineering plastics and epoxy resins; Elastomers and epoxy resins form interpenetrating network polymer (IPN) systems; Toughening and modification of epoxy resin with thermally induced liquid crystal polymer; Toughened epoxy resin by in-situ polymerization of rigid polymers.

These methods can not only improve the toughness of the epoxy resin, but also make its heat resistance, modulus not decrease, or even slightly increase.

Benzyl alcohol, dioctyl phthalate, dibutyl phthalate.

Directly choose Guangzhou Qixiang Synthetic Materials' **** reactive flexible epoxy resin curing agent NH Q640, and all the problems have been solved.

You are asking this question in a very general way.

Need to know can be discussed in detail.

Epoxy resin curing agent brand recommendation Aoldite Araldite epoxy resin curing agent is a double tube storage, not easy to block, super viscosity. Araldite epoxy hardeners are super strong, long-lasting, solvent-free hardeners that are waterproof and can be varnished and sandblasted.

The losses caused will be greater. Don't rely too much on the combination of epoxy floor paint with two-component and orange one-component, there are many owners will think that two-component floor paint is better than one-component, because this is the solvent obtained by proportioning, and the ground effect will be better.

Urea-formaldehyde resin adhesive can be selected polyvinyl acetate, polyvinyl alcohol, etc.

Nanya 128 epoxy resin can be used with water-based epoxy curing agent H205B to make epoxy floor bottom halfway, the primer adds 150% water for easy penetration, and the middle coat adds 100% water to cement sand aggregate to make it thick and strong at one time.

<> "1. What are the epoxy resin curing agents?

1. Aliphatic amines.

Aliphatic amines have fast curing speed, easy operation, high temperature resistance, curing is limited by temperature and humidity conditions, and the paint film is whitened under high humidity conditions.

2. Aromatic amines.

It needs to be cured under heating conditions, and the cured material is heat and corrosion resistant, and is mainly used for heating and curing processes.

3. Amine modified curing agent.

The performance of the coating process and the performance of the cured coating can be changed according to different degrees, and it has the characteristics of corrosion resistance and temperature resistance.

4. Polyamide curing agent.

The paint film has good flexibility, impact resistance and high viscosity, but the judo period is required when the paint is configured, and the curing activity is not high.

5. Anhydride curing system.

It has good mechanical strength and heat resistance, and the cured paint film contains ester bonds, which are susceptible to alkali erosion.

6. Polyisocyanate curing agent.

It has good acid resistance, can be carried out at low temperatures, and is suitable for sub-zero curing.

2. Characteristics of epoxy resin curing agent.

1. It has good alkali resistance, acid resistance and solvent resistance. Can be used in harsh tropical conditions.

2. Various forms, which can be solid from very low viscosity to high melting point.

3. Easy curing, strong adhesion, high adhesion, help to improve adhesion strength.

4. Low shrinkage and good stability. It can make the epoxy resin system have outstanding dimensional stability and durability.

5. Strong mechanical properties, surface leakage resistance, arc resistance.

Summary. Hello, we are glad to answer for you, light-curing cyclic epoxy resins have small viscosity, good mechanical properties and good adhesion.

Hello, we are glad to answer for you, light-curing cyclic epoxy resins have small viscosity, good mechanical properties and good adhesion.

Let's introduce the model!

Hello, there are 5 models.

Epoxy resin curing agent is a chemical reaction with epoxy resin to form a network of three-dimensional polymers, which envelops the composite bone in the network. It is an additive that turns linear resin into a tough body-shaped solid. There are many types included.

Classification of epoxy resin curing agents: (1) Alkaline and acidic curing agents Alkaline curing agents include aliphatic diamines and polyamines, aromatic polyamines, other nitrogen-containing compounds and modified aliphatic amines. Acidic curing agents include organic acids, anhydrides, and boron trifluoride and their complexes.

2) Additive and catalytic curing agent Additive curing agent This kind of curing agent undergoes an addition reaction with the epoxy group to form a part of the chain segment of the curing product, and cross-links the linear molecules into bulk structure molecules through a gradual polymerization reaction, which is also known as melon-type curing agent. Catalytic curing agent This type of curing agent only initiates the epoxy resin, and after the epoxy group is opened, the catalytic epoxy resin itself polymerizes into a network structure to form a homopolymer with ether bonds as the main structure. (3) Visible curing agent and latent curing agent Visible curing agent is a commonly used curing agent, which can be divided into addition polymerization type and catalytic type.

The so-called addition polymerization type is to open the ring of the epoxy group for addition polymerization reaction, and the curing agent itself participates in the three-dimensional network structure. If the amount of this kind of curing agent is too small, the curing product is connected to the epoxy group of the final reaction. Therefore, there is a suitable dosage for this type of curing agent.

The catalytic curing agent is made by ring-opening addition polymerization of epoxy groups in cationic or anionic mode, and in the end, the curing agent does not participate in the network structure, so there is no suitable amount of equivalent reaction; However, increasing the dosage will result in a faster curing rate. Latent curing agent refers to the relative long-term stability at room temperature after mixing with epoxy resin (an epoxy resin generally requires more than 3 months to have great practical value, and the most ideal requires half a year or more than 1 year), and only needs to be exposed to heat, light, moisture and other conditions to start the curing reaction. This type of curing agent basically seals the activity of the curing agent by physical and chemical methods.

Among the obvious curing agents, varieties such as dicyandiamide and adipic acid hydrazide are insoluble in epoxy resin at room temperature, and begin to solidify after dissolving at high temperature, so they also show a latent state. Therefore, in some books, these varieties are also classified as latent curing agents, which can actually be called functional latent curing agents. Because the latent curing agent can be mixed with epoxy resin to make a one-liquid complex, simplifying the application procedures of epoxy resin, its application range from single packaging adhesive to coatings, impregnating paints, potting materials, powder coatings and other aspects.

Latent curing agent has attracted more and more attention in foreign countries, which can be said to be a key topic in research and development.