PVC is made from fossil fuels, including natural gas. The production process also uses sodium chloride. Recycled PVC is broken down into small chips, impurities removed, and the product refined to make pure PVC. It can be recycled roughly seven times and has a lifespan of around 140 years.
For more information, refer to Wikipedia about Sustainability.
PVC, like other plastics, is often accompanied by many impurities after being eliminated and used, and it needs to be sorted before it can be recycled. The early physical recycling and burning recycling methods have been eliminated. The quality of the plastic materials recycled by the former is not good because it is difficult to sort. The latter is harmful to the environment because many harmful gases are released during the burn of PVC to pollute the environment. Therefore, at present, only chemical recycles methods can be used to do this. Chemical recycles can get higher quality recovery, but the cost is high.
We talked about this issue in our post as below,you can read our post in No.6 questions for more details.
Considering most of buyer can learned about the basic information from the marking on conduit body,so we take an example as below,
Information to be marked on conduits:
a) The name of the manufacturer or responsible vendor, or a trademark, or other identifying symbol;
b) The nominal size;
c) The word ‘ELECTRICAL’, ‘HEAVY DUTY’ or ‘HD’;
d) Is marked with the letter ‘T’ . As per AS/NZS 2053 the standard requires that conduits suitable for use in direct sunlight be marked with the letter ‘T’
e) Be marked ‘Solar’.
f) Be marked above informations not exceeding 2m.
PVC is chemically resistant to acids, salts, bases, fats, and alcohols, making it resistant to the corrosive effects of sewage, that’s why it is so popular in sewer piping systems.
It is also resistant to some solvents, this, however, is reserved mainly for uPVC (unplasticized PVC). Plasticized PVC, also known as PVC-P, is in some cases less resistant to solvents. For example, PVC is resistant to fuel and some paint thinners. Some solvents may only swell it or deform it but not dissolve it, but some, like tetrahydrofuran or acetone, may damage it.
For more information, refer to Wikipedia about Chemical.
The detailed description from HB to 5VA is as follows ( UL94 ):
HB: slow burning on a horizontal specimen; burning rate <76 mm/min for thickness <3 mm or burning stops before 100 mm
V-2: burning stops within 30 seconds on a vertical specimen; drips of flaming particles are allowed.
V-1: burning stops within 30 seconds on a vertical specimen; drips of particles allowed as long as they are not inflamed.
V-0: burning stops within 10 seconds on a vertical specimen; drips of particles allowed as long as they are not inflamed.
5VB: burning stops within 60 seconds on a vertical specimen; no drips allowed; plaque specimens may develop a hole.
5VA: Burning stops within 60 seconds on a vertical specimen; no drips allowed; plaque specimens may not develop a hole.
Most of our products have reached V-0 and above standards. This is especially important in the selection of electrical pipes.