Synthetic method of compound blocked polyisocyanates by using multiple sealants to compound and block terminal groups

A technology of polyisocyanate and synthesis method, which is applied in the field of composite polyisocyanate block synthesis, to achieve the effects of reasonable cost, improved performance, and improved stone chipping resistance

Active Publication Date: 2010-08-04
WUHAN RES INST OF MATERIALS PROTECTION
View PDF2 Cites 10 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0021] Aiming at the various problems mentioned above in the preparation of isocyanate blockers by a single blocking agent, the present invention proposes a compound polyisocyanate blocker synthetic method that is compound-blocked with multiple blocking agents. , the same below), 50 to 350 parts of active methylene compounds, 290 to 335 parts of solvents, and stirred

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
  • Synthetic method of compound blocked polyisocyanates by using multiple sealants to compound and block terminal groups
  • Synthetic method of compound blocked polyisocyanates by using multiple sealants to compound and block terminal groups
  • Synthetic method of compound blocked polyisocyanates by using multiple sealants to compound and block terminal groups

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0052] 468 grams of liquefied diphenylmethane-4,4'-diisocyanate, 160 grams of diethyl malonate, 133 grams of propylene glycol methyl ether acetate, 192 grams of naphtha 100 # Add the mixture to the container, stir at 70°C for about 2 hours; add 130 grams of ethyl acetoacetate, stir at 70°C for about 2 hours; add 109 grams of 3,5-dimethylpyrazole in batches, and stir at 80°C , and stir until no NCO groups are detected (about 1 hour).

[0053] The molar ratio of active methylene compound blocking agent (diethyl malonate and ethyl acetoacetate) to pyrazole blocking agent (3,5-dimethylpyrazole) is 2:1.

[0054] Compared with the prior art, the technical progress and advantages of the present invention are obvious, and it solves many problems that have plagued the synthesis of isocyanate blockers with a single blocking agent for a long time.

Embodiment 2

[0056] 386 grams of liquefied diphenylmethane-4,4'-diisocyanate (NCO% is 29%) and 147 grams of hexamethylene diisocyanate biuret, 80 grams of diethyl malonate, 142 grams of methyl isobutyl Base Ketone, 185g Naphtha 100 # Add the mixture to the container, stir for about 2 hours at 75°C; add 182 grams of ethyl acetoacetate, stir for about 2 hours at 75°C; add 120 grams of 3,5-dimethylpyrazole in batches, °C, stir until no NCO groups are detected (about 1 hour).

[0057] The molar ratio of the active methylene compound blocking agent (diethyl malonate and ethyl acetoacetate) to the pyrazole blocking agent (3,5-dimethylpyrazole) was 1.7:1.

[0058] Compared with the prior art, the invention has obvious technical progress and advantages, and solves many problems that have been perplexing the synthesis of isocyanate blockers with a single blocking agent for a long time.

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 synthetic method of compound blocked polyisocyanates by using multiple sealants to compound and block terminal groups, which is characterized in that 300-600 parts of polyisocyanate ( by mass part, the same below), 50-350 parts of active methylene compound and 290-335 parts of solvent are stirred for 1-3 hours at a temperature of 50-90 DEG C; 50-350 parts of another active methylene compound is added to be stirred for 1-2 hours at a temperature of 50-90 DEG C; 20-130 parts of pyrazole derivative compound is added to be stirred at a temperature of 50-85 DEG C in batches until NCO groups can not be detected or NCO% is not higher than 0.2% (about 0.5-2 hours). Compared with the prior art, the invention has improved technology and obvious advantages.

Description

technical field [0001] The present invention relates to polyisocyanate for end-blocking, in particular to a synthetic method for compound polyisocyanate blocker which is compound-blocked with multiple blocking agents. Background technique [0002] In many application fields, single-package polyurethane coatings are gradually replacing two-package polyurethane coatings, and have formed a complete application system. Single-package polyurethane coatings include thermosetting, room temperature curing, light curing and blocked isocyanate types. In single packaging In the coating system, blocked isocyanate has been widely used, especially polyurethane car bottom coating is increasingly in urgent need of appropriate blocked isocyanate. The polymer material in polyurethane car bottom coating has viscoelasticity, which can convert vibration energy into heat energy dissipation, It can effectively reduce structural vibration and noise, and its high attenuation coefficient can reduce t...

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
IPC IPC(8): C07D231/14
Inventor 廖有为李健吴勇钟萍
Owner WUHAN RES INST OF MATERIALS PROTECTION
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