Aging inhibitor RD and 4020 and 4010NA are the largest aging inhibitor in the rubber industry, accounting for 80% of the total production.RD is more prominent in the tire industry.RD is different from other antiaging agents in that its chemical components are complex mixtures and there is no national standard for the content of active ingredients.For a long time, the national standard method of RD is only:
2. Heating decrement
4 softening point, all of these testing data index can't really describe RD internal effective content, also happens to be illegal manufacturer exploiting the loopholes of profit drive, because many of the resin (including synthetic or natural resin) has similar color appearance, if use national standard test, the results are qualified, or even better than true RD experimental data.We found this problem in 2005
In a series of studies and a lot of experimental work, the following problems were found:
1. Partial adulteration
2. Full fake (full resin fake)
3. Four adulterated resins have been found
4. The quality of RD effective content is uneven.(RD valid content mainly of dimer, trimer and four polymers, which plays a main role dimers, we believe that the domestic RD dimer content greater than 25% even if good, many factory didn't reach, so we have to quote buyer total effective content (two, three, four polymers added together, appear very high), actually dimer is very low, only some teens (that everyone should pay attention to).Additional, when entrusting normal detect a branch to measure effective content, must qualitative first, if fake, do not want again quantitative, quantitative also prohibit, the result can misjudge.
These are the problems and experiences we have encountered in our practical work. I hope they are useful to you.For example, RD fakes, this is a picture of three test tubes (left to right),
Adulteration (with insoluble matter),
Adulterated (with insoluble substances),
The genuine article (dissolved in solvent).
Caution: as there are new adulterated substances, sometimes the solvent method will miss detection, we have been using analytical instruments to identify the true.