- Environmentally friendly process of chlorination and alkylation of 4,4'-methylenedianiline compound phenyl ring
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The invention provides an environmentally friendly process method of chlorination and alkylation of a 4,4'-methylenedianiline compound phenyl ring. Protonic acid-hydrochloric acid is used as a chlorine positive ion source, hydrogen peroxide is used as an oxidizing agent, in order to carry out an electrophilic substitution reaction of a phenyl ring amino meta-position of a substrate, and liquid chlorine, sulfuric chloride and other poisonous and harmful substances are not needed. The method has the characteristics of mild process conditions, safety and reliability, high chlorine atom utilization rate, green and environmental protection, and the like; and the by-product only contains reaction water. Di-substituted or tetra-substituted products are convenient to obtain by adjusting feeding mol ratio according to needs, the substrate 'the 4,4'-methylenedianiline compound with an alkylation group' is used as a reference, and under an optimum process condition, chlorination yield of the phenyl ring reaches 95% or above.
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Paragraph 0046-0052
(2018/08/28)
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- Preparation method of 4,4'-methylene-bis-(3-chloro-2,6-diethylaniline)
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The invention discloses a preparation method of 4,4'-methylene-bis-(3-chloro-2,6-diethylaniline). The preparation method comprises the following steps: (1) in a nitrogen protective atmosphere, carrying out reaction on raw materials 2,6-diethylaniline and hydrochloric acid to generate 2,6-diethylaniline hydrochloride, and dropwisely adding formalin to carry out condensation reaction; after the reaction finishes, neutralizing with liquid caustic soda, and carrying out water separation to obtain 4,4'-methylene-bis-(2,6-diethylaniline); (2) dissolving the product in the step (1) in a solvent, and introducing chlorine to carry out chlorination reaction; after the reaction finishes, neutralizing with liquid caustic soda, and carrying out water separation to obtain a 4,4'-methylene-bis-(3-chloro-2,6-diethylaniline) crude product; and (3) dissolving the product in the step (2) in a solvent, decolorizing with activated carbon, cooling to crystallize, filtering, and drying to obtain the final product. The method has the advantages of simple technique, accessible raw materials, low price and high product purity and yield, and can easily implement industrial production.
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Paragraph 0028; 0030; 0031
(2017/01/09)
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- NOVEL CURING AGENTS
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The invention relates to a resin curing agent having the formula (I), wherein R1 to R4 are each individually selected from linear or branched C1 to C5 alkyl, a process for its manufacture, blends of the reaction products, and two-component curable resin systems.
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Page/Page column 3
(2013/02/27)
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- Substituted p,p'-methylene-bis-anilines
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New methylenebis(metachloro)anilines which are chain-lenghtening agents or cross-linking agents for polyurethanes.
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