Wanhua Chemical Group Co., Ltd.

Wanhua Chemical (ningbo) Co., Ltd.

Wanhua Chemical Co., Ltd.

Wenbin Li

Yuan Li

Yonghua Shang

Jingxu Wang

Weiqi Hua

Qiang Li

Jing Li

Peng Wang

Hao Chen

Shuchang Sun

Yong Yu

Jie Chen

Qiao Wang

Xuelei Cui

Ye Sun

Pengfei Wang

Lei Zhao

Wei He

Degang Liu

Jianfeng Li

Fulin Zhu

Qian Wu

Tonghe Li

Jinping Han

Disclosed is a 1,3-bisisocyanatomethylcyclohexane composition and an optical resin prepared therefrom. The composition comprises, based on the weight of 1,3-bisisocyanatomethylcyclohexane, a) 65%-95 wt % of trans-1,3-bisisocyanatomethylcyclohexane; b) greater than 0 and less than or equal to 0.5 wt %, preferably 0.02-0.5 wt % of 1,4-bisisocyanatomethylcyclohexane. Preferably, the 1,3-bisisocyanatomethylcyclohexane composition contains greater than 0 and less than or equal to 600 ppm of 1-isocyanatomethyl-3-methylcyclohexane, based on the weight of 1,3-bisisocyanatomethylcyclohexane. The 1,3-bisisocyanatomethylcyclohexane composition is used for preparing an optical resin, which can be applied to produce an optical lens with a better performance in preventing opacification and optical distortion.

1,3-bisisocyanatomethylcyclohexane composition and optical resin prepared therefrom

A method for preparing isophorone diisocyanate by (1) reacting isophorone with hydrogen cyanide in the presence of a catalyst to obtain isophorone nitrile; (2) reacting the isophorone nitrile obtained in step (1) with ammonia gas and hydrogen in the presence of a catalyst to obtain isophorone diamine; and (3) subjecting the isophorone diamine to a phosgenation reaction to obtain the isophorone diisocyanate, wherein the content of impurities containing a secondary amine group in the isophorone diamine that undergoes the phosgenation reaction in step (3) is ≤0.5 wt. The method reduces the content of hydrolyzed chlorine in the isophorone diisocyanate product, improves the yellowing resistance of the product, and the harm due to presence of hydrolyzed chlorine in the product is reduced.

Method for preparing isophorone diisocyanate

A method for preparing an isocyanate in a gaseous phase by feeding, in the presence or absence of an inert gas, an amine-containing gas stream and a phosgene-containing gas stream into a reaction region, allowing the amine and the phosgene to contact in gaseous forms and undergo a phosgenation reaction in the reaction region, thus preparing the target isocyanate in a gaseous form in the reaction region. The phosgene-containing stream is subjected to preheating and warming before being fed into the reaction region, and the phosgene-containing stream comprises a substance A at a mass fraction of &#x3c;1% before being subjected to the preheating and warming up. Substance A is a NCO group-containing substance and/or an olefinic double bond-containing substance. The method reduces the formation of clogging matter in a heat exchanger and a vessel during the preheating and warming of the phosgene and during the reaction process.

Method for preparing isocyanate in gaseous phase

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Shandong, China

Wenbin Li