Unlock instant, AI-driven research and patent intelligence for your innovation.

Preparation method for TDI trimer matt curing agent low in free monomer content

A monomer content, trimer technology, applied in polyurea/polyurethane coatings, coatings, etc., can solve the problems of solvent recovery, storage problems, long time, etc., and achieve good scratch resistance of the paint film, improve The effect of high flexibility and fullness

Active Publication Date: 2015-09-23
山东信开源科技创新发展有限责任公司 +1
View PDF6 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the high-vacuum thin film evaporation method requires too much investment and requires high process control. At present, the removal process and equipment problems of this method have not been well resolved in China. The content of free isocyanate monomers in most domestic TDI curing agents seriously exceeds the standard. TDI It is difficult to achieve the content within 0.5%, mostly around 1%
This method is an improved process of solvent extraction. Unreacted free isocyanate monomers can be dissolved in mixed hydrocarbons (such as petroleum ether, dimethyl carbonate, n-hexane, cyclohexanebenzene or their mixtures), while the curing agent polymer is It cannot be dissolved and separated from the bottom layer, and then mixed with a hydrocarbon solvent in the upper layer to continue to add a catalyst to react, but it is difficult to control the reaction in a kettle with stirring, and it is easy to produce high polymers or even gels; free isocyanate monohydrates without stirring It is difficult for the body to fully respond
And ethyl acetate, butyl acetate boiling point is low, very easy to form azeotrope with mixed hydrocarbon, conventional underpressure distillation is difficult to remove mixed hydrocarbon, then constantly add and waste a large amount of ethyl acetate, butyl acetate; When distilling, the temperature must be raised, and the time is long. The curing agent in the kettle does not know whether it is still a curing agent under the catalyst and high temperature; in addition, the distilled solvent contains esters and free monomers, which can neither be used nor discharged. become a problem, so how to recover the solvent is difficult
Even if the method is feasible, it is impossible to remove the residual mixed hydrocarbon solvent in the curing agent, which will eventually affect the product performance

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
  • Preparation method for TDI trimer matt curing agent low in free monomer content
  • Preparation method for TDI trimer matt curing agent low in free monomer content

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0021]In the synthesis kettle, add 25 parts of lauryl alcohol and 462 parts of butyl acetate in sequence according to the weight ratio of the formula. When the temperature rises to about 108°C, there will be reflux, and reflux for 2 to 3 hours for dehydration. If no water drops appear in the water separator, then cool down Cooling; when the temperature drops below 40°C, add 486 parts of 2,4-toluene diisocyanate, pass through N 2 Protection, heat up to 75-80°C, keep warm for 0.5-1h, then cool down to 55°C, add 1.8 parts of catalyst A compounded by DMP-30, potassium isooctanoate and butyl acetate, control the temperature at 55-65°C for 4 hours Finally, start to detect NCO, and then detect the NCO value every 0.5h; when the detected NCO is 10±0.5%, add 20 parts of n-butanol and 0.5 parts of potassium isooctanoate catalyst, and control the temperature at 55-60 °C; When the detected NCO is 8.0±0.3%, stop feeding N 2 , add 2.0 parts of benzoyl chloride, 2.7 parts of antioxidant BHE...

Embodiment 2

[0023] In the synthesis kettle, according to the weight ratio of the formula, add 32 parts of lauryl alcohol and 436 parts of butyl acetate in sequence. When the temperature rises to about 108 ° C, there will be reflux, and reflux for 2 to 3 hours for dehydration. If no water drops appear in the water separator, then cool down Cooling; when the temperature drops below 40°C, add 502 parts of 2,4-toluene diisocyanate, pass through N 2 Protection, heat up to 75-80°C, keep warm for 0.5-1h, then cool down to 55°C, add 1.8 parts of catalyst A compounded by DMP-30, zinc naphthenate and butyl acetate, control the temperature at 55-65°C for reaction After 4 hours, start to detect NCO, and then measure the NCO value every 0.5 hours; when the detected NCO is 10±0.5%, add 22 parts of n-butanol and 0.6 parts of zinc naphthenate catalyst, and control the temperature at 55-60 °C ; When the detected NCO is 8.0±0.3%, stop feeding N 2 , add 2.4 parts of phosphoric acid, 3.2 parts of antioxidan...

Embodiment 3

[0025] In the synthesis kettle, 20 parts of lauryl alcohol, 8 parts of cetyl alcohol, and 448 parts of butyl acetate are sequentially added according to the weight ratio of the formula. If there are no drops of water in the medium, cool down and cool down; when the temperature drops below 40°C, add 496 parts of 2,4-toluene diisocyanate, pass N 2 Protection, heat up to 75-80°C, keep warm for 0.5-1h, then cool down to 55°C, add 1.7 parts of catalyst A compounded by PC-41, zinc isooctanoate and butyl acetate, control the temperature at 55-65°C for 4 hours After that, start to detect NCO, and then detect the NCO value every 0.5h; when the detected NCO is 10±0.5%, add 21 parts of n-butanol and 0.5 parts of zinc isooctanoate catalyst, and control the temperature at 55-60°C; When the detected NCO is 8.0±0.3%, stop feeding N 2 , add 2.0 parts of benzoyl chloride, 10102.8 parts of antioxidant and add butyl acetate to dilute to 50±2% solid content, stir for 0.5h, cool down to 40°C, fil...

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 preparation method for a TDI trimer matt curing agent low in free monomer content. According to the formula, the curing agent comprises 2,4-toluene diisocyanate, polyether polyol, long-chain alcohol, a catalyst A, n-butanol, a catalyst B, polymerization inhibitor, antioxidant and a solvent. According to the prepared TDI trimer matt curing agent low in free monomer content, the solid content is 50+ / -2%, the NCO value is 8.0+ / -0.3%, the viscosity (Tu-4 cup) is 15-25 s, the free TDI is smaller than or equal to 0.5%, the toluene tolerance is larger than or equal to 1, and the curing agent does not contain arene and is characterized by being environmentally friendly, good in scratch resistance, good in transparency and the like. Polyurethane paint manufactured through hydroxyl group components is characterized by being high in hardness, high in transparency, good in film scratch resistance, good in leveling property, high in fullness, high in solubility and the like. The environment-friendly curing agent is used for various two-component polyester paint, polyurethane paint, decorative paint, floor paint, priming paint and the like of woodware, metal, plastics and the like.

Description

technical field [0001] The invention relates to a preparation method of a polyurethane curing agent, in particular to a TDI trimer matte curing agent with low free monomer content. Background technique [0002] Two-component polyurethane coatings are generally composed of isocyanate prepolymers and hydroxyl resins, usually called curing agent components and main agent components. According to the different hydroxyl components, they can be divided into acrylic polyurethane, alkyd polyurethane, Polyester polyurethane, polyether polyurethane, epoxy polyurethane and other varieties generally have superior properties such as low film-forming temperature, strong adhesion, high hardness, good wear resistance, chemical resistance and weather resistance, and are currently the most widely used. A kind of paint, mainly used in automobile original factory paint, plastic paint, wood paint, industrial paint, anti-corrosion paint floor paint, electronic paint, fabric leather paint, printin...

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): C09D175/04C08G18/79
CPCC08G18/794C09D175/04
Inventor 许钧强康伦国姚东生阳京辉邓安王会池
Owner 山东信开源科技创新发展有限责任公司