How to identify the true and false antioxidant

How to identify the true and false antioxidant

Antioxidant RD and 4020, 4010NA is the rubber industry in the production and the largest amount of antioxidants, the three accounted for 80% of total output.RD in the tire industry in the application of more sudden.

RD and other antioxidants, its chemical composition is a complex mixture, the active ingredient content without national standards. RD has long been the national standard method only:

1.Appearance;

2.Heating Reduction;

3.Ash;

4.Softening Point; these test data indicators can not really represent the RD effective content, but also just to benefit by the illegal manufacturers drilled loopholes, because many resins (including synthetic or natural resin) also have a similar color appearance, if the national standard test , The results are basically qualified, and some even better than the real RD experimental data. In 2005 we have found this problem.

In a series of studies and a large number of experimental work found the following questions:

1.Partial adulteration;

2.Full leave (whole resin forged);

3.Four adulterated resins have been found;

4.RD effective content of uneven quality. (RD effective content is mainly dimer, trimer and tetramer, which dimer play a major role, we believe that the domestic RD dimer content of more than 25% even if the good, many plants have not reached, had to buy The total effective content of the newspaper (two, three, tetramer plus together, it is very high), in fact, dimer is very low, and some only 10 percent (this point we should pay attention to.) In addition, when commissioned regular testing Department of the measured content of the effective, we must first qualitative, if fake no longer quantitative, and quantitative are not allowed, the results will be mistaken.

The above is our practical work in the problems and experience encountered, we hope to be useful. Example RD fake, this picture three test tubes (from left to right),

1. Adulteration (with insoluble matter)

2. Adulteration (with insoluble matter)

3. genuine (dissolved in solvent).

Reminder: Because there are new adulterated substances, solvent method is sometimes missed, we have been using analytical instruments to identify true and false.