Polymeric processing aids

Other substances are also used as polymerization processing aids, like solvents (e.g. benzyl alcohol) and accelerators (e.g. nonylphenol). These processing aids are not significantly or not to a measurable degree chemically incorporated into the crosslinked polymer. Under the conditions of the epoxy thermoset reaction the epichlorohydrin, for example, is completely decomposed. Under the current, state of the art hardening technology, practically no epichlorohydrin can be detected in the finished product. 

A PVC compound may contain, besides the polymer, the following ingredients stabilizers, plasticizers, extenders, lubricants, fillers, pigments, and polymeric processing aids. Other ingredients also used occasionally include impact modifiers, fire retardants, optical bleaches, and blowing agents. 

Uses Emulsifier surfactant chemical intermediate raw material for surfactants germicide corrosion inhibitor in process plant streams acid scavenger in petrol prods. epoxy hardener curing catalyst vise, index improver for lubricants flotation collector for sulfide ores inhibitor for butadiene polymerization processing aid for metal and textiles... 

Examination of the THF-ethanol-insoluble fraction. This will consist of the base polymer, which will usually be a PVC homopolymer but could be a copolymer of vinyl chloride (VC) with another monomer such as vinyl acetate (VA). Also present may be polymeric processing aids such as Paraloid K120N (90 10 methylmethacrylate ethyl acrylate copolymer), impact modifiers that are totally soluble in THF such as EVA or CPE, and impact modifiers that are partially soluble in THF such as nitrile rubber and SAN fractions from ABS. 

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