Curing agent 4,4'-biphenyl methane diisocyanate prepolymer and preparation method thereof

A technology of diphenylmethane and diisocyanate, applied in 4 fields, can solve the problems of not being able to produce high solid content products, unable to meet the extensive demand for performance, single variety of coating curing agents, etc. The effect of improved performance and low toxicity

Active Publication Date: 2008-07-30
FOSHAN JINGXIN HUIMING TECH CO LTD
View PDF2 Cites 25 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The disadvantages are: the reaction temperature of the preparation method is high, the poisonous solvent xylene is required as a medium, the process is complex, and products with high solid content cannot be obtained; the prepared coating curing agent is single in variety, and the castor oil MDI curing agent imparts to the product. The strength is low and soft, which is far from meeting the wide range of performance requirements of polyurethane coatings and adhesives in the market.

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
  • Curing agent 4,4'-biphenyl methane diisocyanate prepolymer and preparation method thereof
  • Curing agent 4,4'-biphenyl methane diisocyanate prepolymer and preparation method thereof
  • Curing agent 4,4'-biphenyl methane diisocyanate prepolymer and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0040] a. Add 100 grams of molten 4,4,-diphenylmethane diisocyanate and 100 grams of ethyl acetate into the reaction kettle, stir evenly, heat up to 65°C, and add polyethylene adipate glycol dehydrated by vacuum 120 g of propylene glycol ester diol was reacted at 60-70° C. for 2 hours and at 90-100° C. for 1 hour to prepare the modified MDI. b. Under stirring, add dropwise a mixture of 12 grams of trimethylolpropane and 12 grams of ethyl acetate to the reaction kettle at a temperature of 80-90°C, drop it in 2 hours, keep it warm for 1 hour, and then rise Heat the reaction at 90-100°C for 2 hours, then lower the temperature to 60°C. C, add 120 gram ethyl acetate solvents by product solid content requirement, stir, the MDI curing agent that 464 gram solid content is 50% is obtained in discharging, the NCO content of this curing agent is 5.7% (calculated as total solid) after testing 11.4%).

[0041] (Note: 1. The detection of solid content is carried out according to the natio...

Embodiment 2

[0044] a. Add 220 grams of molten 4,4,-diphenylmethane diisocyanate and 50 grams of ethyl acetate in the reaction kettle, stir well, heat up to 65°C, add 30 grams of polyoxypropylene glycol dehydrated by vacuum , react at 70-80°C for 2 hours, and react at 90-100°C for 1 hour to prepare the MDI modified product. b. Under stirring, add dropwise a mixture of 35 grams of trimethylolpropane and 35 grams of ethyl acetate to the reaction kettle at a temperature of 80-90°C, drop it in 1 hour, keep it warm for 3 hours, and then raise Heat the reaction at 90-100°C for 4 hours, then lower the temperature to 60°C. c. Add 10 grams of ethyl acetate solvent according to the solid content of the product, stir evenly, and discharge 380 grams of MDI curing agent with a solid content of 75% and a viscosity of 1800mpa.s (25°C). The NCO content of the curing agent is detected. was 8.4%.

[0045] (Note: The detection viscosity is carried out according to the national standard "GB / T2794-1995 Deter...

Embodiment 3

[0047] a. Add 200 grams of molten 4,4,-diphenylmethane diisocyanate and 50 grams of ethyl acetate to the reactor, stir well, heat up to 65°C, and add 30 grams of polyoxypropylene glycol dehydrated by vacuum , react at 80-90°C for 1 hour, then add 30 grams of polyethylene adipate propylene glycol ester diol that has been vacuum-dehydrated, react at 80-90°C for 1 hour, and react at 90-100°C for 2 hours , to prepare MDI modified products. b. Under stirring, add dropwise a mixture of 31 grams of trimethylolpropane and 31 grams of ethyl acetate to the reaction kettle at a temperature of 80-90°C, drop it in 3 hours, keep it warm for 2 hours, and then rise Heat the reaction at 90-100°C for 2 hours, then lower the temperature to 60°C. c. Add 16 grams of ethyl acetate solvent according to the solid content requirements of the product, stir evenly, and discharge to obtain 388 grams of MDI curing agent with a solid content of 75% and a viscosity of 2300mpa.s (25°C).

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

PropertyMeasurementUnit
viscosityaaaaaaaaaa
viscosityaaaaaaaaaa
impact strengthaaaaaaaaaa
Login to view more

Abstract

The invention relates to a curing agent, namely, 4, 4 (1)-diphenylmethane diisocyanate prepolymer and a preparation method thereof. The method comprises the steps that molten 4, 4(1)-MDI and an organic solvent are added into a reaction vessel, and stirred uniformly, the temperature is raised to 65 DEG C, polyhydric alcohol dehydrated through evacuation is added, to react for 2 to 4 hours at 60 to 100 DEG C, and then an MDI modifier is produced; when being stirred, the mixed liquor of trimethylol propane and the organic solvent is titrated into the reaction vessel for 1 to 4 hour(s), the titration temperature is 60 to 100 DEG C, heat preservation and reaction are performed for 1 to 3 hour(s), then the temperature is raised to 90 to 100 DEG C and the heat preservation and the reaction are performed again for 1 to 4 hour(s), the temperature is reduced, and the organic solvent is added for dilution to appropriate viscosity. The curing agent has the advantages that the application scope is broad, the molecular structure of the polyhydric alcohol can be adjusted according to the requirements of users to produce the prepolymer of polyurethane coating, adhesive, and the curing agent, the storage stability is good, the curing speed is quick, the toxicity is low, the price is low, products with high solid content can be obtained, etc.

Description

technical field [0001] The invention relates to a polyurethane coating, an adhesive curing agent prepolymer and a preparation method thereof, in particular to a 4,4'-diphenylmethane diisocyanate prepolymer and a preparation method thereof. Background technique [0002] At present, the most commonly used polyurethane curing agent production method at home and abroad is to use trimethylolpropane to react with imported toluene diisocyanate (TDI) to form a prepolymer, which has unreacted TDI monomer in the production process Residues, due to its high gas phase toxicity, affect the health of production workers and cause pollution to the environment, and the removal of free TDI requires expensive equipment, and the process is more complicated. The corresponding domestic products have not been cleared. The content of free TDI Both are greater than 2%, much higher than the 0.5% standard stipulated by the European Community implemented internationally. In recent years, the price of ...

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): C08G18/02C09D175/04
Inventor 周建明何绍群
Owner FOSHAN JINGXIN HUIMING TECH CO LTD
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