Waterborne polyurethane elastic dispersion and preparation method thereof

A water-based polyurethane, elastic polyurethane technology, used in polyurea/polyurethane coatings, coatings, textiles and papermaking, etc., can solve the problem of high price of hydroxyl-terminated polydialkylsiloxane, limited filler dosage, and lack of high extinction or matte etc.

Active Publication Date: 2013-05-08
INST OF PROCESS ENG CHINESE ACAD OF SCI +1
View PDF10 Cites 24 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] (3) It is difficult to achieve both extinction and strong transparency by simply relying on the adjustment of the molecular structure of the soft / hard segment polyurethane, and it is difficult to achieve the coating effect that requires a strong frosting feeling purely by relying on water-based polyurethane
On the one hand, the addition of fillers will give water-based polyurethane coatings new properties (such as a matte feel); but on the other hand, the actual content of polyurethane in some areas of coatings is very low, often less than 10%, and a large amount of water is needed to dilute , so the amount of filler is limited, otherwise it is very easy to produce precipitation and cause uneven coating
[0017] However, in the method for preparing water-based polyurethane elastic dispersion disclosed in the prior art, the alkoxy-terminated silane is easily hydrolyzed when it encounters water, and when the added amount is slightly larger, it tends to be excessively cross-linked and aggregated, and the stability of the emulsion is poor, so the added amount is very small. It can have an effect on the hand feeling, but it cannot achieve a high degree of matting or frosting effect; while the price of hydroxyl-terminated polydialkylsiloxane is high, the product is soft, and the abrasion resistance is not good

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
  • Waterborne polyurethane elastic dispersion and preparation method thereof
  • Waterborne polyurethane elastic dispersion and preparation method thereof
  • Waterborne polyurethane elastic dispersion and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0114] A method for preparing an aqueous polyurethane elastic dispersion includes the following steps:

[0115] (1) Add the compound represented by the general formula (I) and / or the hydrophilic crosslinking agent into the three-necked flask, pass in moist air while stirring, stir under the elevated temperature, add the compound represented by the general formula (II), and stir After homogenization, heat and reduce pressure to distill to remove small molecular alcohol to obtain siloxane polymer;

[0116] (2) Then add macromolecular polyol and isocyanate to the siloxane polymer (residue of vacuum distillation) obtained in step (1), and then continue the reaction after heating the mixture to cause chain extension polymerization;

[0117] Or adding a polyurethane prepolymer obtained from macromolecular polyols and isocyanates to the siloxane polymer (residue of vacuum distillation) obtained in step (1);

[0118] Then cool the mixture, add small molecule chain extenders and / or hydrophilic...

Embodiment 1

[0121] A method for preparing an aqueous polyurethane elastic dispersion includes the following steps:

[0122] (1) Add 1 kg of the compound of general formula (I) into a three-necked flask, add air with a humidity of 40% under stirring, and after stirring at 60°C for 3 hours, add 5 kg of the compound of general formula (2), stir well and heat and reduce pressure Distillation to remove small molecular alcohol to obtain siloxane polymer; wherein, R in general formula (I) 1 Dodecyl, R 2 Tetradecyl, R 3 Is ethyl; R in general formula (II) 4 , R 5 Methyl, m=4;

[0123] (2) Add 100kg of polyester diol SP-2060 (Shanghai Shanji Chemical) and 113kg of polyisocyanate IPDI (Pasto Company) to the siloxane polymer obtained in step (1), and react 0.5 at 90°C. h Carry out chain extension polymerization; then cool to 60°C, add 3 kg of hydrophilic cross-linking agent DMPA (Pasto Company) and small molecule chain extender 1,4-butanediol (Beijing Yili Chemical Company, CP) 0.1 kg, react for 2h to c...

Embodiment 2

[0125] A method for preparing an aqueous polyurethane elastic dispersion includes the following steps:

[0126] (1) Add 6kg of compound of general formula (I) and 12kg of compound of general formula (2) into a three-necked flask, and mix with 60% air humidity under stirring. Stir at 50℃ for 2 hours, stir well and heat under reduced pressure for distillation Removal of small molecular alcohols to obtain siloxane polymers; wherein, R in general formula (I) 1 Cetyl, R 2 Dodecyl, R 3 Is ethyl; R in general formula (II) 4 , R 5 Is a methyl group, m=4;

[0127] (2) Add 100kg of polyester carbonate diol PCD964 (Shanghai Shanji Chemical) and 23kg of polyisocyanate MDI (Pasto Company) to the siloxane polymer obtained in step (1), and react for 3h at 70°C Carry out chain extension polymerization; then cool to 55°C, add 8kg of hydrophilic cross-linking agent sodium ethylenediaminoethanesulfonate A95 (Degussa) and small molecule chain extender 1,6-hexanediol (Beijing Yili Chemical Company, CP...

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
glossaaaaaaaaaa
transmittivityaaaaaaaaaa
Login to view more

Abstract

The invention relates to a preparation method of waterborne polyurethane elastic dispersion. The method comprises the following steps: (1) synthesizing a siloxane polymer: polymerizing a compound as shown in formula (I) and the compound as shown in formula (II) to get the siloxane polymer; and (2) preparing the waterborne polyurethane elastic dispersion, wherein the raw material comprises the siloxane polymer obtained in the step (1). After the elastic polyurethane dispersion provided by the invention forms a film, the waterborne polyurethane elastic dispersion has not only excellent tensile strength, rebound elasticity, wear resistance, water resistance and ethanol tolerance, but also soft and smooth hand feeling and high light transmission; and an additional filler is not required, a product has high light extinction or frosted appearance by only adjusting components, after the film is formed, the elastic polyurethane dispersion is soft, and the elastic polyurethane dispersion is suitable for paper, cloth, leather and other soft substrates, and the preparation process is simple and easy to operate.

Description

Technical field [0001] The invention relates to an aqueous polyurethane elastic dispersion and a preparation method thereof, in particular to an aqueous polyurethane elastic dispersion suitable for soft substrates such as paper, cloth, leather and the like, and a preparation method thereof. Background technique [0002] Polymers containing multiple urethane groups (-NHCOO-) on the main chain of the polymer structure are usually called polyurethanes. Aqueous polyurethane is a polyurethane system in which water replaces organic solvents as the dispersion medium. It has the advantages of no pollution, safety and reliability, excellent mechanical properties, good compatibility, and easy modification. [0003] Waterborne polyurethane has a special soft / hard core-shell structure, and its application in soft substrate coating such as leather, synthetic leather, paper, PVC gloves, textiles, etc. is rapidly expanding. The soft substrate coating has different requirements for the flexibilit...

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): C08G18/61C08G18/12C09D175/04D06M15/653
Inventor 张冬海陈运法张建森罗楠
Owner INST OF PROCESS ENG CHINESE ACAD OF SCI
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