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:
Nov. 29, 2016
Filed:
Jun. 12, 2012
Jianming Zhou, Wuhan, CN;
Shaoqun He, Wuhan, CN;
Jianming Zhou, Wuhan, CN;
Shaoqun He, Wuhan, CN;
J&H Xiangyang Chemical Co., Ltd., Wuhan, Hubei, CN;
Abstract
Provided are a modified diphenylmethane diisocyanate (MDI) biuret curing agent and preparation method thereof, the curing agent being prepared by reacting dibasic alcohol, water and MDI in an organic solvent. The preparation method includes the steps of: firstly, using the dibasic alcohol to modify a part of MDI, dividing the metered water into multiple parts, and adding the water by multiple times; after adding the first part of water, reacting firstly under 70-100° C., then heating up to 120-140° C. for reaction; secondly, lowering the temperature to 70-100° C., adding the second part of water; and repeating the above processes until all the metered water is added, to produce the MDI curing agent with partial biuret structure. The curing agent is mainly used as the curing agent of polyurethane coating and adhesive agent, and has a higher NCO percentage and a slower curing speed than that of common MDI prepolymer curing agents.