Isocyanurate-containing polyisocyanate composition with stable chromaticity, and preparation method thereof

Patent metadata

Field	Value
Publication number	US-12516191-B2
Application number	US-202018043148-A
Country	US
Kind code	B2
Filing date	Sep 25, 2020
Priority date	Sep 25, 2020
Publication date	Jan 6, 2026
Grant date	Jan 6, 2026

Abstract

The present invention provides an isocyanurate-containing polyisocyanate composition with stable chromaticity, and a preparation method thereof, belonging to the technical field of polyisocyanate composition preparation. The preparation method comprises: an isocyanate monomer being polymerized in the presence of a catalyst, after the reaction is terminated, obtaining a prepolymer, subjecting the prepolymer to separation treatment and heat treatment, and obtaining the polyisocyanate composition containing isocyanurate; based on the weight of the polyisocyanate composition, the cleavable amine content of the polyisocyanate composition is less than or equal to 20 ppm. By means of controlling the cleavable amine content of the polyisocyanate composition, the present invention causes the resulting isocyanurate-containing polyisocyanate composition to have stable storage chromaticity, and the present invention has a chrominance increase of ≤10 Hazen when stored at 40° C. for 12 months.

First claim

What is claimed is:

1 . A preparation method for an isocyanurate-containing polyisocyanate composition with stable chromaticity, comprising the following steps:
(1) reacting an isocyanate monomer in the presence of the catalyst; (2) adding a terminator into the system to terminate the reaction when the reaction reaches a target conversion rate, so as to obtain a prepolymer; (3) subjecting the product obtained in step (2) to separation treatment to remove the unreacted isocyanate monomer to obtain a crude isocyanurate-containing polyisocyanate composition; and (4) subjecting the crude polyisocyanate composition obtained in step (3) to heat treatment under high temperature and reduced pressure to obtain the isocyanurate-containing polyisocyanate composition with stable chromaticity; wherein step (2) further comprises adding a phosphate salt into the prepolymer after terminating the reaction; based on a total weight of the polyisocyanate composition, a cleavable amine content of the polyisocyanate composition is less than or equal to 20 ppm; the cleavable amine is a decomposition product of a catalyst used in preparing the isocyanurate-containing polyisocyanate composition.

2 . The preparation method according to claim 1 , wherein the phosphate salt is selected from one or more of potassium dihydrogen phosphate, sodium dihydrogen phosphate, potassium hydrogen phosphate and sodium hydrogen phosphate;
and/or a hydrogen molar amount in the phosphate salt is 50-100% of a catalyst molar amount; and/or step (2) comprises stirring at 0-30° C. for 10-120 min after adding the phosphate salt.

3 . The preparation method according to claim 1 , wherein the catalyst in step (1) is added in a form of an alcohol solution;
and/or an amount of the catalyst is 0.001%-0.1% of a mass of the isocyanate monomer.

4 . The preparation method according to claim 1 , wherein the isocyanate monomer in step (1) is an aromatic or aliphatic diisocyanate containing an NCO group and 4-20 carbon atoms.

5 . The preparation method according to claim 1 , wherein the terminator in step (2) is selected from an organic acid and/or an acylating agent;
and/or an amount of the terminator is 100-150% of a catalyst molar amount.

6 . The preparation method according to claim 1 , wherein in step (3), the product obtained in step (2) is subjected to the separation treatment by a thin-film evaporator to remove the unreacted isocyanate monomer.

7 . The preparation method according to claim 1 , wherein in step (4), a process condition of the heat treatment of the crude polyisocyanate composition under high temperature and reduced pressure comprises treating the composition at a temperature of 90-180° C. and a pressure of less than or equal to 200 Pa for 5-60 min.

8 . The preparation method according to claim 1 , wherein the catalyst is a quaternary ammonium base and/or a quaternary ammonium salt.

9 . The preparation method according to claim 1 , wherein the cleavable amine is one or more of trimethylamine, triethylamine, tripropylamine and tributylamine.

10 . The preparation method according to claim 1 , wherein the catalyst is selected from one or more of choline hydroxide, (2-hydroxyethyl) trimethylammonium hydroxide, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, benzyltrimethylammonium hydroxide, 1-adamantylammonium hydroxide, hexamethonium hydroxide, a tetraalkylammonium salt of organic weak acid, hydroxypropyltrimethylammonium formate, hydroxypropyltrimethylammonium acetate, hydroxypropyltrimethylammonium octanoate, hydroxypropyltrimethylammonium decanoate, hydroxyethyltrimethylammonium formate, hydroxyethyltrimethylammonium acetate and hydroxyethyltrimethylammonium decanoate.

11 . The preparation method according to claim 1 , wherein after stored at 40° C. for 12 months, the polyisocyanate composition has a chromaticity increment of less than or equal to 10 Hazen.

12 . The preparation method according to claim 3 , wherein a mass concentration of the catalyst is 0.25%-50% in the alcohol solution.

13 . The preparation method according to claim 4 , wherein the isocyanate monomer is selected from one or more of hexamethylene diisocyanate, isophorone diisocyanate, cyclohexyl dimethylene diisocyanate, xylylene diisocyanate, dicyclohexylmethane diisocyanate, norbornane dimethylene diisocyanate, cyclohexyl diisocyanate, lysine diisocyanate, tetramethyl xylylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, toluene diisocyanate, methylcyclohexyl diisocyanate, naphthalene diisocyanate, p-phenylene diisocyanate and diphenylmethane diisocyanate.

14 . The preparation method according to claim 5 , wherein the terminator in step (2) is selected from one or more of formic acid, benzoic acid, benzoyl chloride and diisooctyl phosphate.

15 . The preparation method according to claim 7 , wherein in step (4), a process condition of the heat treatment of the crude polyisocyanate composition under high temperature and reduced pressure comprises treating the composition at a temperature of 150-180° C. and a pressure of less than or equal to 20 Pa for 10-30 min.

Assignees

• Wanhua Chemical Group Co Ltd
• Wanhua Chemical Ningbo Co Ltd

Inventors

• Wang Nuancheng
• Shang Yonghua
• Shi Bin
• Wang Yuqi
• Sun Lidong
• Fan Weijing
• Yan Chengyue

Classifications

• C08G18/1825

  having hydroxy or primary amino groups · CPC title

• C08G18/10

  Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step · CPC title

• C08G18/092

  oligomerisation to isocyanurate groups · CPC title

• C08G2115/02

  to isocyanurate groups · CPC title

• C07D251/34

  Cyanuric or isocyanuric esters · CPC title