Sulfonic acid type of hydrophilic polyurethane chain extender preparation

Sulfonic acid type of hydrophilic polyurethane chain extender preparation: waterborne polyurethane (WPU) replace the organic solvent with water as dispersion medium, the system does not contain or contain very small amounts of organic solvents, has noncombustible, non-toxic, no pollution and energy saving etc, and thus gained widespread application. But traditional WPU emulsion because of its low solid content (less than 40%, mass fraction, the same below) caused by dry film-forming rate is slow, since the early poor thickening and adhesion force is low, which limits its application. At present about the preparation of high solid content of waterborne polyurethane emulsion fluid research reported less.

In order to expand the application range of the WPU, sulfonic acid type WPU was studied at home and abroad, the product of the solid content is only about 40%, the highest elongation at failure is only about 900%. With self-made 1, 2-2 hydroxy - 3 - propyl sulfonic acid sodium (DHPA) as hydrophilic chain extender, use the emulsion of high performance polyurethane emulsion prepared by.

The main raw materials. Isophorone diisocyanate (IPDI), Germany imported products; Poly (tetrahydrofuran - co - propylene oxide) glycol (Ng210), the number average molecular weight of 1000, Japan imported products; DHPA, purity is more than 95%, the self. N - methyl - 2 - pyrrolidone (NMP), analysis of pure, on sea ray huasheng technology co., LTD. Product; Two n-butyl amine, analysis of pure, tianjin xinhua fine chemical products; Two lauric acid tin, analysis of pure tin mass fraction 19%, Germany imported products.

The preparation of WPU emulsion. Will be a certain amount of Ng210 under 110 ℃ with a thermometer, condenser tube and agitator four flask vacuum dewatering in 2 h, cooling ventilation with nitrogen to 30 ℃, join the metering IPDI and small amounts of catalyst two lauric acid tin, heating to 70 ~ 75 ℃ reaction to NCO group the mole fraction of 3%, with n-butyl amine titration to determine the reaction end point.

After cooling to 60 ℃ DHPA according to certain quality ratio of dissolved in a small amount of NMP, then slowly add the NMP solution to the system, in 70 ℃ reaction 115 h. Then reaction system cooled to 30 ℃, and slowly add a certain amount of deionized water to the system, in the violent mixing under the condition of emulsifying, quick WPU emulsion.

WPU film preparation will WPU emulsion coating on the sample board of polytetrafluoroethylene, natural dry place at room temperature for 7 d film-forming, 24 h, and then under 60 ℃ dry WPU was made by the film.

Analysis and test the particle size and distribution. Type ZetaPLUS granulometry is used to test the WPU emulsion (expressed in average diameter dn) and its particle size distribution (PDI) with polydispersity index. The micro morphology. With 100 SX transmission electron microscopy (TEM) observation of WPU micro morphology of latex particles and correction of emulsion particle size and its distribution. Solid content. By thermogravimetric method was developed for the determination of WPU emulsion solid content. Viscosity meter with digital display NDJ - 8 s type viscosity determination of WPU emulsion viscosity.




Chinese name: Diethyl toluene diamine(DETDA)

Diethyltoluenediamine packing： net weight 200KG/ galvanized iron drum (a small cabinet pallet loaded 16 tons), 1000KG/IB barrels (a small cabinet loaded 18 tons or 23 tons of ISOTANK).


Storage stability. State in room temperature placed 1 months later said the storage stability of the WPU emulsion. Freeze-thaw stability. Take a certain amount of the emulsion, in - 20 ℃ refrigerator frozen 18 h, to thaw at room temperature for 6 h again, repeat the operation more than five times, record the number of emulsion appeared gel, to determine the freeze-thaw stability of WPU emulsion.

The high temperature stability. Will be placed in an airtight jar in the emulsion samples at 60 ℃ and 80 ℃ respectively placed under constant temperature, emulsion, check record emulsion settling or flocculation time, to determine the high temperature stability of the WPU emulsion.

The tensile strength and elongation at failure. (GB/T528-1998 was developed for the determination of WPU emulsion tensile strength and elongation at failure. DSC differential scanning calorimetry (DSC) analysis on what type of DSC instrument. Sample must be placed in the desiccant drying after film, to prevent the influence of the moisture content of DSC analysis. Test temperature for - 50 ~ 250 ℃, the heating rate of 10 ℃ / min. The entire process under nitrogen protection.

In polymer material, C1s depth information for 5 ~ 10 nm, can estimate about a few nm thickness of PMMA cover on the surface of PU - EG, of course, the thickness is not uniform. This is also caused by spline with horizontal lines and the cause of the PMMA surface roughness increases greatly. Also shows that PMMA on PU surface between PMMA and PU - EG there is a strong cooperation with the key.

PTMEG - 1000 for the soft PU elastomer due to its soft segment of low relative molecular mass, soft segment length of chain is shorter, not easy to form the perfect crystal; H12MDI 2, 4, 4 'and 4' isomer, including 4, 4 'isomer and trans - trans and cis - cis and cis - trans isomer three kinds of space, a variety of configurations H12MDI regularity of the influence of hard segment, the hard segment hard to crystallization, which is formed by the micro phase separation of hard segment area formed in the crystal grain size of nanometer level, so it was not significantly affect the optical performance.

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