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An epoxy resin phenolic coating crosslinking agent
2017-8-3 16:16:35
An epoxy resin phenolic coating crosslinking agent
It is well known that several products prepared by phenol, aldehydes and lipids polyamines are widely used in many industrial fields as the crosslinking agents of low temperature or medium temperature epoxy resin crosslinking agent or wet surface.
When the content of the unreacted phenol in the epoxy phenolamine crosslinking agent is more than 5%, it can be harmful to the user. In turn, an unresponsive epoxy crosslinking agent with high levels of amine can also easily cause rash.
In recent years, the demand of phenol, aldehyde, amine-type epoxy resin with low viscosity and unreacted has been increasing. The need for cross-linking agents with low levels of unreacted is also increasing. However, it is difficult to produce a product that meets all of these requirements, namely that the unreacted phenol, unreactive amine content is low and the viscosity is low.
This paper introduces the exploration of this aspect in recent years. The epoxy-phenolic amine crosslinking agent was prepared by the reaction of phenol, aldehyde and amine.
The reaction products of phenol, aldehyde and amine can be prepared by one of the following four methods:
1. The phenol first reacts with the aldehyde, and then the amine is added to the product.
The amine reacts with the aldehyde first, and then the phenol is added to the product.
3. The phenol first mixes with the amine, then the aldehyde is added to the mixture, and the three components react together to get the product.
4. The three components of phenol, aldehydes and amines react together and get the product. The third method is used in industry.
The unreacted phenol content in the reaction products prepared in the first method is low, and it reacts with phenol and aldehydes prior to joining the amine. However, this method inevitably produces high viscosity reaction products. If the amount of aldehydes is large, the viscosity will increase further. If a large amount of diluent is not used, this product is difficult to use. The use of a large amount of diluents will adversely affect the physical and chemical properties of the crosslinked epoxy resin.
In the second method, before adding aldehydes, amines first react with aldehydes. In fact, the use of a large amount of aldehydes will result in a highly viscous reaction mixture, which makes it difficult to stir; But in order to reduce the amount of unreacted phenol in the reaction products, a relatively large number of aldehydes must be used, so the viscosity of the reaction products increases.
Chinese name: Diethyl toluene diamine(DETDA)
Diethyltoluenediamine Uses:
It is well known that several products prepared by phenol, aldehydes and lipids polyamines are widely used in many industrial fields as the crosslinking agents of low temperature or medium temperature epoxy resin crosslinking agent or wet surface.
When the content of the unreacted phenol in the epoxy phenolamine crosslinking agent is more than 5%, it can be harmful to the user. In turn, an unresponsive epoxy crosslinking agent with high levels of amine can also easily cause rash.
In recent years, the demand of phenol, aldehyde, amine-type epoxy resin with low viscosity and unreacted has been increasing. The need for cross-linking agents with low levels of unreacted is also increasing. However, it is difficult to produce a product that meets all of these requirements, namely that the unreacted phenol, unreactive amine content is low and the viscosity is low.
This paper introduces the exploration of this aspect in recent years. The epoxy-phenolic amine crosslinking agent was prepared by the reaction of phenol, aldehyde and amine.
The reaction products of phenol, aldehyde and amine can be prepared by one of the following four methods:
1. The phenol first reacts with the aldehyde, and then the amine is added to the product.
The amine reacts with the aldehyde first, and then the phenol is added to the product.
3. The phenol first mixes with the amine, then the aldehyde is added to the mixture, and the three components react together to get the product.
4. The three components of phenol, aldehydes and amines react together and get the product. The third method is used in industry.
The unreacted phenol content in the reaction products prepared in the first method is low, and it reacts with phenol and aldehydes prior to joining the amine. However, this method inevitably produces high viscosity reaction products. If the amount of aldehydes is large, the viscosity will increase further. If a large amount of diluent is not used, this product is difficult to use. The use of a large amount of diluents will adversely affect the physical and chemical properties of the crosslinked epoxy resin.
In the second method, before adding aldehydes, amines first react with aldehydes. In fact, the use of a large amount of aldehydes will result in a highly viscous reaction mixture, which makes it difficult to stir; But in order to reduce the amount of unreacted phenol in the reaction products, a relatively large number of aldehydes must be used, so the viscosity of the reaction products increases.
Chinese name: Diethyl toluene diamine(DETDA)
Diethyltoluenediamine Uses:
The product is identical to Ethancure 100 and Lonza DETDA 80, DETDA is very effective polyurethane elastomer chain extender; also be used as polyurethane and epoxy resin curing agent, epoxy resin of an antioxidant, industrial oils and lubricants . In addition, also as intermediates in organic synthesis.Especially for the RIM (reaction injection molding), is important in the field of spray polyurea chain extender species. Also can be used for casting polyurethane elastomer (CPU) and a curing agent, epoxy curing agent, epoxy resin of antioxidants, lubricants and industrial oils other antioxidants.
In the above methods, the viscosity of the reaction product can be reduced effectively by adding an excessive amine, but if the crosslinking agent contains a large amount of unreacted amine, it can easily cause the user's rash. In addition, epoxy resins used with this crosslinking agent can absorb carbon dioxide from the air and turn white, thus damaging the appearance of cross-linked resin. In particular, when cross-linking agents are used for multilayer coatings, the absorption of carbon dioxide causes deep separation, which the user does not want.
The results showed that, with a certain proportion, the crosslinking agent prepared by the third method had a low viscosity under certain reaction conditions, and the residual phenol content of the unreacted was greatly reduced. These products are further reacted with acrylonitrile, and the reaction products have low levels of unreacted.
Instance: m g adjacent methyl phenol n g a mixture of meta-xylene diamine was loaded with a stirring reactor, under nitrogen gas to heat up, to the specified temperature, put x g 37% formalin solution in a certain period of time added to the mixture, under the required temperature reaction time, and then gradually heating up, steamed out excess water.
In the mixture of yacrylonitrile, which is added to the countermeasure, stirring for A period of time, in addition to A small amount of benzyl alcohol diluent, A pale yellow product (cross-linking agent A), its performance index is listed in the table. To change the ratio of phenol, aldehyde, amine and acrylonitrile, repeat the above process, respectively, to crosslinking agent B and C.
Contrast example: ml, a mixture of phenol and nl grams of meta-xylene 2 by being loaded with stirring reactor, under nitrogen gas to heat up, to the specified temperature, xl grams of 37% formalin solution in a certain period of time added to the mixture, steaming out excess water. A product (crosslinking agent D) changes the ratio of phenols, aldehydes, amines and acrylonitrile, repeating the above process, and the crosslinking agent E. The addition of acrylonitrile can significantly reduce the content of free amine in crosslinking agent.
Copyright: Zhang Jia Gang YaRui Chemical co.,Ltd
In the above methods, the viscosity of the reaction product can be reduced effectively by adding an excessive amine, but if the crosslinking agent contains a large amount of unreacted amine, it can easily cause the user's rash. In addition, epoxy resins used with this crosslinking agent can absorb carbon dioxide from the air and turn white, thus damaging the appearance of cross-linked resin. In particular, when cross-linking agents are used for multilayer coatings, the absorption of carbon dioxide causes deep separation, which the user does not want.
The results showed that, with a certain proportion, the crosslinking agent prepared by the third method had a low viscosity under certain reaction conditions, and the residual phenol content of the unreacted was greatly reduced. These products are further reacted with acrylonitrile, and the reaction products have low levels of unreacted.
Instance: m g adjacent methyl phenol n g a mixture of meta-xylene diamine was loaded with a stirring reactor, under nitrogen gas to heat up, to the specified temperature, put x g 37% formalin solution in a certain period of time added to the mixture, under the required temperature reaction time, and then gradually heating up, steamed out excess water.
In the mixture of yacrylonitrile, which is added to the countermeasure, stirring for A period of time, in addition to A small amount of benzyl alcohol diluent, A pale yellow product (cross-linking agent A), its performance index is listed in the table. To change the ratio of phenol, aldehyde, amine and acrylonitrile, repeat the above process, respectively, to crosslinking agent B and C.
Contrast example: ml, a mixture of phenol and nl grams of meta-xylene 2 by being loaded with stirring reactor, under nitrogen gas to heat up, to the specified temperature, xl grams of 37% formalin solution in a certain period of time added to the mixture, steaming out excess water. A product (crosslinking agent D) changes the ratio of phenols, aldehydes, amines and acrylonitrile, repeating the above process, and the crosslinking agent E. The addition of acrylonitrile can significantly reduce the content of free amine in crosslinking agent.
Copyright: Zhang Jia Gang YaRui Chemical co.,Ltd
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