PVC polymer

PVC polymer plus special plasticizers are used to produce flexible tubing which has good chemical resistance. 

Different types of PVC exist on the market. The two principle types are suspension and paste-forrning PVC the latter includes the majority of emulsion PVC polymers. The plasticizer appHcations technologies associated with these two forms are distinctly different and are discussed separately. Details of the polymerization techniques giving rise to these two distinct polymer types can be found in many review articles (5,28) (see ViNYLPOLYMERS, (VINYL Cm ORIDE POLYPffiRS)). 

The plasticization of PVC accounts for the vast majority of plasticizer sales. However, significant amounts of plasticizers are used in non-PVC polymers and this may become increasingly important in the future. Although PVC stands alone in its abiUty to accept and retain large quantities of commercial plasticizer, effective plasticization of other resins using slightly modified plasticizers may be possible if certain conditions specific to the polymer of interest are met. 

Blends with PVC. Nitrile mbber may be blended with poly(vinyl chloride) (PVC) by the polymer producer by two different techniques (1) blending of NBR latex with PVC latex followed by co-coagulation and drying, or (2) physically mixing the soHd NBR and PVC powder in mixing equipment such as an internal mixer. NBR—PVC polymer blends are well known for the good ozone resistance that is imparted by the PVC. 

If PVC polymer particles are mixed, at room temperature, with plasticisers the immediate product may take one of two forms. If there is insufficient plasticiser to fill all the gaps between the particle a mush will be produced. If all the voids are filled then the particles will become suspended in the plasticiser and a paste will be formed. In the case of conventional granular polymer, or with emulsion polymer cenospheres, the particles are too large to remain in suspension and will settle out. Therefore compounds used in paste-processes must use polymers with a small particle size. On the other hand there is a lower limit to this, since small particles will have a very high surface/volume ratio and measurable plasticiser absorption will occur at room temperature to give a paste whose viscosity will increase unduly with time. As a consequence paste polymers have an average particle size of about 0.2-1.5 ptm. 

Many additives are used with PVC polymers such as plasticizers, antioxidants, and impact modifiers. Heat stabilizers, which are particularly important with PVC resins, extend the useful life of the finished product. Plastic additives have been reviewed by Ainsworth. 

As indicated, this process is defined as mechanical recycling, since the PVC polymer is not broken down into its monomers. Yet, a main difference with classical mechanical recycling is that in the latter the full PVC formulation is kept intact. Here the components that make up the full formulation are separated. This results in the important advantage that the Vinyloop process can deal with rather complicated formulations. According to Solvay the regenerated PVC is comparable in quality to the primary product. 

C13-0004. The polymer known as PVC is used to make plastic pipes. The monomer used to make PVC is vinyl chloride. Draw a segment of the PVC polymer containing four repeat units. See Figure 13-3 for the structure of vinyl chloride. 

More than 95% of vinyl chloride is converted to PVC polymer. 

Whereas the use of conventional fast atom bombardment (FAB) in the analysis of polymer/additive extracts has been reported (see Section 6.2.4), the need for a glycerol (or other polar) matrix might render FAB-MS analysis of a dissolved polymer/additive system rather unattractive (high chemical background, high level of matrix-, solvent- and polymer-related ions, complicated spectra). Yet, in selected cases the method has proved quite successful. Lay and Miller [53] have developed an alternative method to the use of sample extraction, cleanup, followed by GC in the quantitative analysis of PVC/DEHP with plasticiser levels as typically found in consumer products (ca. 30 %). The method relied on addition of the internal standard didecylphthalate (DDP) to a THF solution of the PVC sample with FAB-MS quantitation based on the relative signal levels of the [MH]+ ions of DEHP and DDP obtained from full-scan spectra, and on the use of a calibration curve (intensity ratio m/z 391/447 vs. mg DEHP/mg DDP). No FAB-matrix was added. No ions associated with the bulk of the PVC polymer were observed. It was... 

Since the UV degraded C-PVC still contains substantial amounts of the initial CHC1-CHC1 structure, one can expect the chlorine radicals evolved to also initiate the zip-dehydrochlorination of these structures. The resulting chlorinated polyenes will then be further destroyed by the laser irradiation, so that finally all the C-PVC polymer is converted into a purely carbon material within a fraction of a second. 

Antimony tris(isooctylthioglycolate), for PVC polymers, 25 671 Antimony trisulfide, 3 57, 64—65 Antimussol, commercial defoamer,... 

Chlorinated fluorocarbons (CFCs), 21 591 Chlorinated glycolurils, 73 109-110 Chlorinated hydantoins, 13 110 Chlorinated hydrocarbons (CHC) contamination by, 23 111—112 for PVC polymers, 25 674 Chlorinated isocyanurates end use of chlorine, 6 135t as pool sanitizers, 26 175-176 Chlorinated methanes... 

Clay fillers, for PVC polymers, 25 675 Clay liners, in landfill design, 25 879 Clay minerals, 6 685-686 in coal, 6 718... 

Epoxy phosphate esters, 10 383-384 Epoxy plasticizers, for PVC polymers, 25 674... 

Boliden s Kaldo process of, 14 742-743 Isasmelt process of, 14 743-745 Kivcet process of, 14 739-740 Outokumpu process of, 14 745 QSL process of, 14 740-742 Lead stabilizers, for PVC polymers, 25 671 Lead storage battery, 14 783. See also Lead-acid batteries Lead-calcium alloy batteries... 

Organic corrosion inhibitors, 7 815-816 Organic costabilizers, for PVC polymers, 25 672... 

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