PVC Processing Equipment

In plasticised PVC the main function of a lubricant is to prevent sticking of the compound to processing equipment. This is brought about by selecting a material... 

Special attention needs to be put on the possibility of contamination with PVC. The latter decomposes under SSP conditions and produces hydrochloric acid, which has to be eliminated from the process gas stream to protect the processing equipment [123], The PVC residues will manifest themselves as black non-melting particles in the downstream process. There is an option to eliminate the decomposed PVC residue by colour sorting after the SSP process. 

This resin is used primarily in corrosion-resistant coating and piping of process equipment, as a compromise between poly(vinyl chloride) (PVC) and the much more expensive fluorocarbons. 

Initial work to process PVC resin into manufactured products led many investigators to believe that the polymer was not a useful one. Some of the performance shortcomings of PVC were overcome by the advent of plasticizers and development of copolymers, both of which were responsible for the subsequent commercial growth of PVC. Although resins with improved stability and processing characteristics have since been developed, the tremendous growth of vinyl plastics is in no small measure due to the development of effective heat stabilizers as well as efficient processing equipment. 

In plasticized PVC it is common practice to incorporate a lubricant whose main function is to prevent sticking of the compound to processing equipment [14]. The material used should have limited compatibility such that it will sweat out during processing to form a film between the bulk f the compound and the metal surfaces of the processing equipment. The additives used for such a purpose are known as external lubricants. 

Chem. Deschp. Wh. petrolatum USP CAS 8027-32-5 EINECS/ELINCS 232-373-2 Uses Emollient, base, solvent, and carrier for cosmetics and pharmaceuticals (creams, lotions, petrol. Jellies, ointments, dental adhesives), foods (animal feed supplement, fruit/veg. coatings) sanitary lubricant in food prod, machinery rust-preventive coating in food processing equipment carrier in adhesive tapes and compds. lubricant for textile, paper, PVC shoe polishes food-contact applies. 

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