This article has been in the making for a long time, but it was delayed due to the need for experimental verification of the complicated content involved. The article wants to investigate the principle of TGIC in some depth from the performance of the use of TGIC. Including the following aspects: 1, different parameters of TGIC on the impact of curing speed 2, different parameters of TGIC on the physical properties of the film delay 3, different parameters of TGIC on the accelerated aging performance 4, different parameters of TGIC own melting point and decomposition temperature differences in analysis, of course, there are more complex aspects of the impact factors, including cooking, steam, etc. This article will first talk about the phenomenon, do the analysis, and share some experimental methods. I would like to leave the more detailed data analysis to later when I have enough test results.

All of the above I would like to start from the source of TGIC synthesis existing most widely used synthetic route: cyanuric acid + large amounts of epichlorohydrin + catalyst (quaternary ammonium-based phase transfer catalyst) the above products + granular / flake sodium hydroxide TGIC extremely by-products of epichlorohydrin solution and solid sodium chloride and by-product water (saturated brine) separation of sodium chloride and aqueous solution (more ways in order also Water washing (optional) of TGIC and its by-products of epichlorohydrin solution Removal of epichlorohydrin (many ways with different efficiencies) TGIC and its by-products are added to methanol and then crystallized TGIC crystals and by-products of methanol solution Separation of crystal TGIC (with some by-products) granulation drying, etc. into finished products.

The underlined part above is the only two steps in the TGIC production process to improve the purity of TGIC itself. These are the washing of the solution and the crystallization process, respectively.

In case of poor separation, the above situation will occur as follows: TGIC has a large amount of end groups containing chlorine that are not completely closed loop.

Such TGIC will have a general performance, chlorine content is slightly high, but with polyester powder coatings made out of high curing speed, in cold weather or curing conditions can not reach when the film has a good initial performance. But the film performance decay quickly, the delay performance is very poor.

In other words, TGIC products that are not purified well will have faster curing speed, but the cured coating film is not as complete. In the laboratory of powder coating, we can test different TGIC curing speed by the following ways and means. 1, the same formula of horizontal fluidity, tilt fluidity comparison 2, the same formula of gelation time comparison 3, the same formula of time delay performance test (note the difference of TGIC dispersion effect of different granulation process) 4, DSC/DTA test TGIC itself thermal decomposition Temperature 5, TGIC 200 ℃ 10 minutes yellowing / decomposition test (note that a small amount of 1-2 grams of sample testing)

All the above tests are aimed at the effect of residual quaternary ammonium promoters on epoxy bond opening in the finished TGIC. For the discussion of the delayed performance and aging performance also need suitable samples to do the test.

The picture test is the DSC melting point and decomposition temperature test of several representative TGICs. The decomposition temperature is above 280 degrees, and the actual market is still full of poor quality TGIC, whose decomposition temperature is even lower than 220 degrees. Such products will make the coating film TG lower, make the powder storage stability worse, coating film delay performance worse, coating film water resistance worse, coating film transfer poor and a series of problems. Later on, our laboratory will make a series of validation laboratory for different parameters of TGIC samples to give the corresponding test data and analysis.