Does blister packaging raw material PVC contain chlorine?

In addition, it can also be determined by measuring whether the material contains chlorine, but because vinyl chloride copolymer, neoprene, polyvinylidene chloride, chlorinated polyvinyl chloride, etc. all contain a relatively high proportion of chlorine, it is necessary to develop color by pyridine response to identify. Note that before the test, the sample must be extracted with ether to remove the plasticizer. Test method: Dissolve the sample taken with ether and benzene in tetrahydrofuran, filter out the insoluble components, add methanol to precipitate it, and after extraction Dry below 10°C. Do not use 1ml of pyridine to react with the dried small sample. After a few minutes, add 2 drops of 5% sodium hydroxide methanol solution (1g sodium hydroxide is dissolved in 20ml methanol), and immediately observe the color, 5min and 1h and then observe again. Different chlorine-containing plastics can be identified by their color.