Preparation of water-based polyurethane coating crosslinking agent

Preparation of water-based polyurethane coating crosslinking agent

The polypropylene glycol into 3 flask with a thermometer and vacuum pump plug, in 120 ~ 140 ℃, 2 h 0.1 MPa under the condition of vacuum dehydration, then add the right amount of TDI according to the dosing raio into three flask, 65 ℃, 90 min reaction, sampling, in reaction with n-butyl amine method, a residual NCO content, until a NCO content to the theoretical value.

Temperature will drop to 30 ℃, 4 o, adding suitable amount of acetone system viscosity reduction, and then put in the process of the products from three flask put people in the ice water bath, cool to 0 ~ 5 ℃, under high shear force, add a certain amount of end capping agent sodium bisulfite and sodium sulfite solution accelerator, reaction 40 min, ivory sealing type waterborne polyurethane; Add a certain proportion of emulsifier AEOO and OEPO82, and add the ionized water emulsifying 1h at high speed.

There are three stages of the synthesis of the water-based polyurethane crosslinking agent: prepolymerization, sealing and emulsification. The experiment was analyzed and discussed in the process of optimizing the synthesis process, and finally the optimized synthesis technology was obtained.

The quality score of a NCO before and after the sealing end of the sealing end was determined by the di-n-butyl amine method, and the sealing rate was calculated by (1).

The closure rate = times 100% (1)

Type: W0 - the quality score of NCO before the end - NCO

W1 - the quality score / % of NCO

The fastness of rubbing fastness is measured by GB/t3920-1997 (textile colour fastness test.

The rupture strength was determined by GB/t3923-1997 "tensile performance test of textile fabric" in the HDO26N electronic fabric strength meter.




Chinese name: Diethyl toluene diamine(DETDA)

Diethyltoluenediamine Raw material ：

TDA industrial, Sichuan production

Ethylene (Et) polymer grade, Shanghai production

TEA industrial imports

A reagent grade additives


Infrared spectroscopy (Fq 'IR) analysis. The preparation of the water-based polyurethane membrane was scanned in the Nicolet5700 Fourier transform infrared spectrometer, and the sample infrared spectrogram was obtained.

Differential scanning (DSC) analysis. Take a small amount of samples, using DSC differential thermal analyzer to determine, study the deblocking temperature and test temperature range from 25 to 300 ℃, 20 ℃ / min heating rate.

Waterborne polyurethane is composed of soft segment and hard segment block copolymer, including polymer polyol composition of soft segment, isocyanate and small molecule chain extender reaction to form hard segment.

It mainly controls the elasticity, low temperature performance and water resistance of ionic polyurethane. Due to soft segment different polyurethane molecular structural differences, led to the emulsion properties, synthesis of waterborne polyurethane film mechanical properties, etc. There are large differences.

Polyols can be classified into polyether polyols and polyester polyols. The mechanical strength, heat resistance and oil resistance of polyester polyurethane are higher than the polyether type, and its hardness is high. The etheric bonds of polyurethane are flexible, flexible, excellent in low temperature and hydrolysis.

This project requires the synthesis of polyurethane crosslinking agent with excellent water resistance, so choose polyether polyol as a soft segment. Type test is the following several kinds of polyether polyols as soft segment, in the case of other process conditions are the same for synthetic reaction, get series samples, then analysis the performance of the samples.

Copyright: Zhang Jia Gang YaRui Chemical co.,Ltd 

Diethyl toluene diamine(DETDA)  http://www.yaruichem.com