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

Preparation method of chdi modified mdi base polyurethane microcellular elastomer

A microporous elastomer and polyurethane technology, applied in the field of materials, can solve the problems of shortening the service life, increasing the complexity of the reaction system, and affecting the performance, so as to prolong the service life, improve the resistance to photo-oxidation, and improve the wear resistance. Effect

Active Publication Date: 2019-10-18
上海凯众材料科技股份有限公司
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, since the above two technical schemes all use aromatic isocyanate as a raw material, the nitrogen atom adjacent to the benzene ring forms a large ∏ bond conjugated system, which is easily damaged under the action of light (especially ultraviolet light), heat and oxygen The photooxidation reaction occurs, which destroys the main chain structure of the macromolecule, resulting in a greatly shortened service life of the material
Technologists often solve this technical shortcoming by adding anti-ultraviolet agents and antioxidants. However, anti-ultraviolet agents and antioxidants can only delay this photooxidation reaction to a certain extent, and the addition of both will increase the overall reaction system. The degree of complexity also has a certain impact on the performance of the final product

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 of chdi modified mdi base polyurethane microcellular elastomer

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0018] The concrete method that present embodiment prepares CHDI modified MDI-based polyurethane microcellular elastomer is:

[0019] Mix 5 moles of MDI and 1 mole of CHDI evenly, and react with 2.632 moles of polyethylene adipate diol with a number-average molecular weight of 1000 at 80°C for 2 hours to obtain an end-NCO group content of 7wt%. terminal isocyanate prepolymer.

[0020] 100 mass parts of polyethylene adipate glycol with a number average molecular weight of 1000 and 10 mass parts of 1,4-butanediol, 4 mass parts of water, 0.8 mass parts of retardation catalyst (Dabco 1027), 0.8 parts by mass of a foam stabilizer (Dabco DC 2585) were mixed uniformly to prepare a chain extender composition.

[0021] Using a low-pressure foaming machine, the prepolymer and the chain extender composition are mixed and reacted according to the ratio of the isocyanate index of 95%, and the reaction liquid is injected into a mold at 65°C, aged for 25 minutes, demoulded, and then heated ...

Embodiment 2

[0027] The concrete method that present embodiment prepares CHDI modified MDI-based polyurethane microcellular elastomer is:

[0028] Mix 4 moles of MDI and 1 mole of CHDI evenly, and react with 1.341 moles of polycaprolactone diol with a number-average molecular weight of 2000 at 80°C for 2 hours to obtain a terminal-NCO group content of 8 wt%. Polymer.

[0029] 100 mass parts of polycaprolactone diol with a number average molecular weight of 2000 and 10 mass parts of 1,4-butanediol, 4 mass parts of water, 0.8 mass parts of delayed catalyst (Dabco 1027), 0.8 Mass parts of the foam stabilizer (Dabco DC2585) were mixed evenly to prepare a chain extender composition.

[0030] Using a low-pressure foaming machine, the prepolymer and the chain extender composition are mixed and reacted at a ratio of isocyanate index of 96%, and the reaction material liquid is injected into a mold at 65°C, aged for 25 minutes, demolded, and then heated at 110°C After aging for 16 hours, a CHDI-mo...

Embodiment 3

[0032] The concrete method that present embodiment prepares CHDI modified MDI-based polyurethane microcellular elastomer is:

[0033] Mix 4 moles of MDI and 1 mole of CHDI evenly, and react with 1.07 moles of polytetrahydrofuran ether diol with a number average molecular weight of 2000 at 80°C for 2 hours to obtain a terminal isocyanate prepolymer with a terminal -NCO group content of 10 wt%. .

[0034] 100 parts by mass of polytetrahydrofuran ether glycol with a number average molecular weight of 2000 and 10 parts by mass of 1,4-butanediol, 4 parts by mass of water, 0.8 parts by mass of retardation catalyst (Dabco 1027), 0.8 parts by mass The foam stabilizer (Dabco DC 2585) was mixed uniformly to prepare the chain extender composition.

[0035] Using a low-pressure foaming machine, the prepolymer and the chain extender composition are mixed and reacted at a ratio of isocyanate index of 96%, and the reaction material liquid is injected into a mold at 65°C, aged for 25 minutes...

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 discloses a method for preparing CHDI (1,4-Cyclohexane Diisocyanate) modified MDI (4,4'-Diphenylmethane Diisocyanate) based polyurethane micropore elastomer. The method comprises the following steps: 1) enabling excessive MDI and CHDI to react with high molecular weight dihydric alcohol of which the number-average molecular weight is 1000-3000 at 70-90 DEG C so as to form a prepolymer of which the tail end isocyanate group content is 7-10wt%; 2) mixing the high molecular weight dihydric alcohol with small molecular weight dihydric alcohol of which the molecular weight is 48-200, a foaming agent, a retardance catalyst and a foam stabilizer so as to obtain a chain extending agent composition; 3) mixing the prepolymer with the chain extending agent composition according to indexes of isocyanate in a ratio of 95-105%, injecting into a mold of 60-80 DEG C, and performing casting molding; and 4) aging, demolding, and performing later aging. As the CHDI which is not sensitive to light oxidation reaction is introduced, on the basis that the excellent mechanical properties of the MDI based polyurethane micropore elastomer are maintained, the light oxidation resistance is improved, then the wear resistance of a product is improved, and the service life of the product is prolonged.

Description

technical field [0001] The present invention relates to the field of materials, in particular to polyurethane microcellular elastomers, more specifically to MDI (4,4'-diphenylmethane diisocyanate) modified by CHDI (1,4-cyclohexane diisocyanate) )-based polyurethane microcellular elastomer preparation method. Background technique [0002] Polyurethane microcellular elastomer is a chemical system formed by pouring a liquid reaction mixture into a mold cavity. The chemical raw materials used mainly include isocyanate, polyol, chain extender, foaming agent, catalyst, foam equalizer, etc.; in the preparation process It mainly includes the following chemical reactions: polyol reacts with isocyanate to form a gel reaction of carbamate, and isocyanate reacts with water to form urea and CO 2 foaming reaction. The wear resistance of polyurethane elastomer is very outstanding, which is about 3 to 5 times that of natural rubber, and it also has excellent shock absorption and buffer pe...

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 Patents(China)
IPC IPC(8): C08G18/76C08G18/75C08G18/66C08G18/42C08G18/48C08G18/64C08G18/10C08G101/00
Inventor 杨亚军李明英胡冬良范春晓
Owner 上海凯众材料科技股份有限公司