The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 22, 2011
Filed:
Oct. 16, 2007
Jiansheng Ding, Yantai, CN;
Jianfeng Chen, Beijing, CN;
Hongke Zhang, Yantai, CN;
Haikui Zou, Beijing, CN;
Weiqi Hua, Yantai, CN;
Pengyuan Zhang, Beijing, CN;
Shuchang Sun, Yantai, CN;
Guangwen Chu, Beijing, CN;
Limin Xu, Beijing, CN;
Jiansheng Ding, Yantai, CN;
Jianfeng Chen, Beijing, CN;
Hongke Zhang, Yantai, CN;
Haikui Zou, Beijing, CN;
Weiqi Hua, Yantai, CN;
Pengyuan Zhang, Beijing, CN;
Shuchang Sun, Yantai, CN;
Guangwen Chu, Beijing, CN;
Limin Xu, Beijing, CN;
Ningbo Wanhua Polyurethanes Co., Ltd., Ningbo, CN;
Beijing University of Chemical Technology, Beijing, CN;
Abstract
The present invention provides a method of preparing polymethylene-polyphenyl-polyamine (briefly referred to as polyamine, DAM), in which a high gravity rotating bed is used as the mixing reactor of formaldehyde and aniline hydrochloride, the mixing solution of aniline hydrochloride and circulation solution and the formaldehyde are fed into the high gravity rotating bed reactor proportionally to carry out mixing and condensation reaction under a condition of a very high gravity; the materials leaving the high gravity rotating bed reactor is introduced into a stirred vessel to proceed with the pre-condensation reaction and obtain a condensation solution; and the process steps of heating, molecular rearrangement, neutralization, water washing and purification, etc. are completed to obtain the refined DAM. With the method according to the present invention, the main by-products is obviously reduced in the condensation process, the phenomenon of deposit attaching to the inner walls of circulation pipes and heat exchanger and blockage are prevented in the condensation process, the impurity content is low in the refined DAM, and the subsequent product MDI has a lighter color, the product quality is stable and may be improved to a certain extent.