Coating with dicyandiamide crosslinking agent

Coating with dicyandiamide crosslinking agent,Dicyandiamide, also known as the cyanide diamine, dicyandiamide, English abbreviated DICY, molecular weight 84, white crystal, melting point 207 ? ? - 209. Dicyandiamide and epoxy value of 0.12 of the theory of bisphenol A type epoxy resin with herself for 100:2.52, actual usage is generally 2% 4%, 200 ? / crosslinking conditions for 30 min.

Dicyandiamide is the most widely use epoxy powder coating of the crosslinking agent. Produced by calcium cyanide ammonia reaction. Of DICY/epoxy resin system still exist the following problems: the insoluble cause heterogeneity of the DICY sexual problems reflected in the low gloss, poor mobility and in individual case after making the crosslinked coating uneven appearance; DICY itself is a water-soluble compound, usually will increase the sensitivity of crosslinked coating for water.

In order to improve its low reaction performance, need to join catalysts or promoters, such as imidazole (or bonus imidazole) to speed up the reaction. Directly to the dicyandiamide with such promoter the resulting mixture is called acceleration dicyandiamide, replace groups, introduced by derivative, the most commonly used for aryl of dicyandiamide, to replace dicyandiamide. Replace dicyandiamide representative varieties is adjacent - methyl benzene 2 guanidine (Ortho - tolyl - biguanide).

Its preparation is by dicyandiamide and condensation in the presence of o-toluidine in hydrochloric acid. Neighbors - about 136 ? cresyl two guanidine melting point, the introduction of adjacent cresyl was improved and the compatibility of bisphenol A epoxy resin, and it has the very high functionality, so compared with dicyandiamide, the crosslinking performance is greatly improved. Recommended by the crosslinking temperature for 160 ? / 20 min - 180 ? / 10 min.

Because instead of DICY solubility in the resin is better than DICY itself many, influence the storage stability of system. Therefore, must by selecting the appropriate type and content of catalyst to hope to get the crosslinking time and comprehensive balance the relationship between the storage stability of the acceptable.

Two cyanide diamine (melamine), abbreviated DICY or DCD. Is the dimer of cyanogen amine and guanidine cyano derivatives. The chemical formula C2H4N4. A white crystalline powder. Soluble in water, alcohol, ethylene glycol and dimethyl formamide, hardly soluble in ether and benzene. Stable when dry.




Chinese name: Diethyl toluene diamine(DETDA)

Diethyltoluenediamine packing： net weight 200KG/ galvanized iron drum (a small cabinet pallet loaded 16 tons), 1000KG/IB barrels (a small cabinet loaded 18 tons or 23 tons of ISOTANK).


Using dicyandiamide with acid reaction, can make various kinds of guanidine salt. Dicyandiamide and phenyl nitrile reaction of benzene second 3 get together cyanogen amine is paint, laminate, molding powder of intermediates.

Dicyandiamide and formaldehyde reaction of dicyandiamide resin, can be used as a dye fixing agent.

Dicyandiamide compound fertilizer to control the activity of nitrifying bacteria, the transformation of nitrogen in the soil speed adjustment, reduce the loss of nitrogen, improve the use efficiency of fertilizer.

In medicine, used in preparing guanidine nitrate, sulfa drugs, etc.; Also used for producing thiourea, cellulose nitrate stabilizing agent, rubber vulcanization accelerator, steel surface hardener, artificial leather, filler, adhesive, etc. By dicyandiamide and formic acid reaction to pharmaceutical intermediates 5 - nitrogen impurity cytosine. As a source of nitrogen to nitrogen doped carbon materials.

Calcium cyanamide hydrolyzed calcium hydrogen cyanide ammonia slurry, the reduced pressure filtration to remove calcium hydroxide filter residue, to filtrate flux into the carbon dioxide to precipitate calcium in the form of calcium carbonate, get cyanamid fluid. Under the condition of alkali aggregate, then through filtering, cooling crystallization, separation, drying, two melamine.

Produce dicyandiamide when maximum speed of temperature and pH on: 50 ℃ at pH 9.7; 80 ℃ when the pH is 9.1; 100 ℃ at pH 8.8. Controlled polymerization under these conditions, then the cooling crystallization, separation, drying, for a quick finished product dicyandiamide. Industrial dicyandiamide content is 99%, product consumption per ton of lime nitrogen (more than 21% of nitrogen) 4239 kg.

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Diethyl toluene diamine(DETDA)  http://www.yaruichem.com