Polyvinyl Chloride
Polyvinyl chloride, or PVC, is a polymerized form of Vinyl chloride. It take the form of a chain of Vinyl Chloride molecules.
It is the third most common plastics after polyethylene (PE) and polypropylene (PP).
In Situ production
PVC can be produced on Mars by polymerization of vinyl chloride, itself a product of the hydrochlorination of acetylene.
Polymerization requires the use of water as a suspension medium, a polymerization initiator and other additives. A typical initiator is dioctanoyl peroxide. The reaction is exothermal and requires cooling. The reaction product is long chain polymers of PVC, that are dried and pelletized. Degassed vinyl chloride is recycled[1].
The virgin PCV is modified using a number of additives such as plasticizers and U.V stabilizers. Heat stabilizers are also generally added, such as Tin mercaptides. These may represent from 2 to 4% of the product mass.
Uses
PVC is used for piping and insulation of electric cables.
