Polyacrylate modified water-based enclosed isocyanate curing agent and preparation method thereof

A technology of blocked isocyanate and polyacrylate, applied in the direction of polyurea/polyurethane coatings, coatings, etc., can solve the problems of difficult isocyanate group movement, reduced curing efficiency, coating performance defects, etc., to achieve low cost and improved appearance , The effect of stable product quality

Active Publication Date: 2014-11-05
CNOOC CHANGZHOU PAINT & COATINGS IND RES INST +2
View PDF1 Cites 24 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, unfortunately, the blocked polyisocyanates currently used in two-component waterborne polyurethane systems generally have the following three problems: ① high price
When the blocked isocyanate curing agent is mixed with hydroxyl polyacrylate resin, compatibility problems often occur, resulting in defects in the corresponding coating performance; ③Low curing efficiency
During the curing process of the coating, when the blocked isocyanate is unblocked and a part of the isocyanate undergoes a crosslinking reaction, the residual isocyanate group in the same curing agent molecule is difficult to move due to steric hindrance, and it is difficult to crosslink with the hydroxyl polyacrylate reaction, resulting in reduced curing efficiency

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Polyacrylate modified water-based enclosed isocyanate curing agent and preparation method thereof
  • Polyacrylate modified water-based enclosed isocyanate curing agent and preparation method thereof
  • Polyacrylate modified water-based enclosed isocyanate curing agent and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

preparation Embodiment 1

[0042] 2. the concrete operation of preparation embodiment 1 polyisocyanate semi-block (A1)

[0043] With 30.86 grams of isophorone diisocyanate and 10 grams of solvent methyl ethyl ketone as the primer, add 12.70 grams of blocking agent methyl ethyl ketone oxime dropwise at 60 ° C. The molar ratio of blocking agent to polyisocyanate is 1.05:1, and the drop is completed within 2 hours , after the dropwise addition was completed, it was incubated at 60° C. for 5 hours and discharged to obtain a polyisocyanate semi-block (A1), which was stored for future use.

preparation Embodiment 2

[0044] 3. the concrete operation of preparation embodiment 2 polyisocyanate semi-blocks (A2)

[0045] The concrete operation of preparation is identical with embodiment 1, and difference is: the 12.70 gram blocking agent methyl ethyl ketoxime of embodiment 1 is replaced with 14.02 gram blocking agent 3,5-dimethylpyrazole, obtains polyisocyanate half-block (A2) , save for later use.

[0046] (2) Preparation of hydroxyl-containing polyacrylate

[0047] The method for preparing the hydroxyl-containing polyacrylate of the present invention is: the mixture of all monomers, chain transfer agents and initiators is evenly added dropwise to the solvent to carry out free radical polymerization, and the specific operations are as follows:

[0048] Using 10-50wt% solvent as a primer, 5-15wt% carboxyl-containing vinyl monomers, 2-20wt% acrylate monomers containing primary or secondary hydroxyl groups, 1-10wt% The ε-caprolactone-modified vinyl monomer containing primary hydroxyl group, 5-...

preparation Embodiment 4

[0069] 2. The specific operation of preparation example 4 polyacrylate modified water-based blocked isocyanate curing agent (D1)

[0070] 53.56 grams of polyisocyanate semi-blocks (A1) (containing residual NCO group 0.132 moles) prepared in Example 1 are mixed with hydroxyl-containing polyacrylate B (containing hydroxyl 0.125 moles), wherein polyisocyanate semi-blocks (A1 ) in the isocyanate group and the mol ratio of the hydroxyl of the hydroxyl-containing polyacrylate (B) is 1.06:1, add the catalyst dibutyltin dilaurate (0.047wt% for A1+B total mass) of 0.1 gram, raise Temperature to 80°C, kept at 80°C for 5 hours, then added 12 grams of neutralizing agent triethylamine (5.6wt% of the total mass of A1+B) to neutralize, at 200 rev / min the stirrer Add 250 g of deionized water (1.17 times the total mass of A1+B) under stirring for emulsification, heat up to 70°C, and distill under reduced pressure to extract the solvent to obtain a polyacrylate modified water-based blocked isoc...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention relates to a polyacrylate modified water-based enclosed isocyanate curing agent and a preparation method thereof. The curing agent is obtained by neutralizing and emulsifying a prepolymer formed by polyisocyanate semi-enclosed object and hydroxyl-containing polyacrylate, and the mole ratio of NCO to OH is 1-1.15:1. The hydroxyl-containing polyacrylate is prepared by: taking 10-50wt% of a solvent as the base material, and dripping a mixture composed of 5-15% of a carboxyl-containing vinyl monomer, 2-20% of a primary hydroxyl or secondary hydroxyl-containing acrylate monomer, 1-10% of a primary hydroxyl-containing epsilon-caprolactone modified vinyl monomer, 5-70% of other monomer containing a vinyl structure, 0.1-5% of a chain transfer agent and 0.05-3% of an initiator into the base material. The sealant and polyisocyanate for preparation of the polyisocyanate semi-enclosed object are in a mole ratio of 1.05-1.5:1. The curing agent has good miscibility with the matrix resin, high curing efficiency, low cost, flexibility and impact resistance.

Description

technical field [0001] The invention relates to a polyacrylate modified water-based blocked isocyanate curing agent and a preparation method thereof. Background technique [0002] Waterborne polyurethane has been widely used in the fields of coatings, inks and adhesives due to its excellent comprehensive properties. Waterborne polyurethane is mainly divided into one-component and two-component systems. One-component water-based polyurethane is convenient for construction, but its chemical resistance is insufficient; two-component water-based polyurethane is generally composed of water-based hydroxyl-containing polyacrylate dispersion and water-based polyisocyanate curing agent. , excellent coating performance. However, the two-component water-based polyurethane needs to be prepared and used immediately when it is used, and there is a pot life, which is not conducive to construction. In order to solve the contradiction between the performance and workability of the two-com...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C08G18/80C08G18/62C09D175/04C08F220/18C08F220/14C08F222/20
CPCC08G18/0823C08G18/6233C08G18/807C08G18/8077C09D175/04
Inventor 庄振宇许飞胡中陈卫东张汉青祝宝英朱柯马吉康
Owner CNOOC CHANGZHOU PAINT & COATINGS IND RES INST
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap