Toxicity is the most mentioned negative issue about TGIC, after that there are various positive comments about it. Excellent heat resistance, weathering properties, catalytic properties, electrical properties. Of course, similar to the plasticizing effect of reducing the size of the problem of powder coating glass transition is also considered a pain point, but through the design of polyester glass transition temperature increase can be completely no longer bother.

Where does the toxicity come from?

The industry believes that the toxicity (allergenicity, teratogenicity) comes from its very body.

It is often said that the TGIC of family A is easy to allergic, and it will be fine if you change to family B. Then a different scenario will have someone say that family B's is more allergic than family A's.

Are these statements correct? I think they are all plausible. I will talk about my opinion below.

To state a few facts:

① Allergy is first caused when TGIC itself enters the pores of the skin, or dissolves into the oil or sweat secreted from the pores.

② the solubility of TGIC in cold water is actually not high, but in hot water the solubility will be very high.

③The stimulation of TGIC to human pores is different for different indicators.

What to do? Reduce the exposure of pores for good protection, choose employees who do not like to sweat, reduce the ambient temperature to shrink pores to reduce the dissolution of TGIC, and choose TGIC with low irritation.

The article is about TGIC, so let's talk about what is meant by low irritation TGIC.

In a word, low chlorine content and low dust. The dust is more related to the granulation method, which will be discussed in detail next time.

High chlorine content = high irritation, can be divided into three aspects of understanding

First, inorganic chlorine, some actively added quaternary ammonium chloride catalyst, sodium chloride by-products, these chlorine in contact with the skin will eventually form irritating products such as HCl form, irritation and open the pores of the skin.

Second, organic chlorine high chlorine content of TGIC is also poor quality entrained by-products to more, which contains chlorine organic by-products will increase the water solubility of TGIC.

Third, the residual epichlorohydrin itself is also a factor that irritates the eyes and skin. The existing technical level of control to the PPM level, excellent manufacturers are able to stabilize the control to below 100PPM.

In the national standard, the quality of TGIC is divided into two levels of qualified 0.6% and superior 0.4% according to the chlorine content. The standard use of oxygen bottle combustion method is also more accurate, but the general TGIC manufacturers to test the efficiency of the use of a simple chemical titration. Chemical titration test data + 0.1 is almost the exact value. In other words, according to the chemical titration data, the qualified 0.5% and the excellent 0.3%.

To summarize the above, excluding the effect of particulate dust, to choose a low allergenic TGIC we can try to choose a product with a chlorine content of 0.3% or less. It is true that every TGIC manufacturer can control this indicator to a very low range or even below 0.2% without considering the cost. Low control of indicators and good cost control is the embodiment of a company's technical strength.

So how to determine the quality of TGIC without titration instruments and reagents? I will organize some simple test methods for your reference in the next article.