Vinyl chloride plastics

PoIy(vinyl chloride), PVC, is one of the most versatile of polymers, and the following forms have important applications rigid (unplasticized) grades, plasticized compounds, copolymers and blends. This is perhaps surprising since it is one of the least stable polymers, for which reason much of the early development was concerned with copolymers and with plasticized compositions. 

The monomer is now almost exclusively obtained from ethylene, which has displaced the older acetylene-based process. There is some evidence that vinyl chloride is carcinogenic and there are legal requirements limiting exposure to the monomer. 

Polymerization is by free-radical-initiated reaction, in either suspension or emulsion processes in water at about SC C. In the suspension process, polyvinyl alcohol, incompletely hydrolysed PVAC, or gelatine, are used as a colloid stabilizer with peroxide initiators. The emulsion process employs emulsifiers, such as sodium lauryl sulphate and water-soluble persulphate initiators. Mass polymerization gives PVC powders with characteristics different from those of suspension polymer. 

Some stabilizers are effective in improving weathering behaviour. Lead compounds are good heat stabilizers basic lead carbonate or tribasic lead sulphate are favoured stabilizers but are toxic. The stearate, palmitate and octoate salts of Cd, Ba, Ca, Zn are increasingly used, but toxicity limits the range of applications for Cd. Organo-tin compounds are also effective stabilizers, especially for transparent products, but may also be somewhat toxic. 

Successful processing of unplasticized or rigid PVC (UPVC) requires lubricants, such as lead or calcium stearates, stearic acid or hydrocarbon waxes. UPVC is frequently extruded, and so lubricants melting at 100-120°C are most effective for extrusion at 165°C. UPVC is also widely used in sheet form, obtained by compression moulding multiple plies of calendered foil. 

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By far the largest volume synthetic alcohol is 2-ethylexanol [104-76-7] CgH gO, used mainly in production of the poly(vinyl chloride) plasticizer bis(2-ethylhexyl) phthalate [117-81-7], commonly called dioctyl phthalate [117-81-7] or DOP (see Plasticizers). A number of other plasticizer... 

Fig. 2. The effect of antimony oxide on the oxygen index of poly(vinyl chloride) plasticized with dioctyl phthalate (DOP), (—...

In the case of poly(vinyl chloride) plastics, the FWA is mixed dry with the PVC powder before processing or dissolved in the plasticising agent (see Vinyl polymers). Polystyrene, acrylonitrile—butadiene—styrene (ABS), and polyolefin granulates are powdered with FWA prior to extmsion (2,78) (see... 

The Cg—0 2 branched, odd and even, linear and internal olefins are used to produce improved flexible poly(vinyl chloride) plastics. Demand for these branched olefins, which are produced from propylene and butylene, is estimated to be increasing at a rate of 2% per year. However, the growth of the linear a-olefins is expected to slow down to a rate of 5% per year from 1992 to 1997 (3), as opposed to growth rates of 7—10% in the 1980s. 

Phthahc anhydride (1) is the commercial form of phthaUc acid (2). The worldwide production capacity for the anhydride was ca 3.5 x 10 metric tons ia 1993, and it was used ia the manufacture of plasticizers (qv), unsaturated polyesters, and alkyd resins (qv) (see Polyesters, unsaturated). Sales of terephthahc acid (3) and its dimethyl ester are by far the largest of any of the benzenepolycarboxyhc acids 14.3 x 10 t were produced in 1993. This is 80% of the total toimage of ah. commercial forms of the benzenepolycarboxyhc acids. Terephthahc acid is used almost exclusively for the manufacture of poly(ethylene terephthalate), which then is formed into textiles, films, containers, and molded articles. Isophthahc acid (4) and trimehitic anhydride (5) are commercial products, but their worldwide production capacities are an order of magnitude smaller than for terephthahc acid and its dimethyl ester. Isophthahc acid is used primarily in the production of unsaturated polyesters and as a comonomer in saturated polyesters. Trimehitic anhydride is used mainly to make esters for high performance poly(vinyl chloride) plasticizers. Trimesic acid (6), pyromehitic dianhydride (7), and hernimehitic acid (8) have specialized commercial apphcations. The rest of the benzenepolycarboxyhc acids are not available commercially. 

Vinyl acetate plastics Vinyl alcohol plastics Vinyl chloride plastics Vinyl plastics... 

Vinyl chloride plastics Group of plastics whose resins are derived from the polymerization of vinyl chloride and other unsaturated compounds. 

Polyfvinyl acetate), uses of, 242 Poly(vinyl butyral), uses of, 1222 Poly(vinyl chloride), plasticizers in, 1216... 

D 2219 Vinyl Chloride Plastic Insulation for Wire Cable 60 C Operation. 

To whom does the chemical industry sell all of its chemicals It is its own best customer. It is estimated that over 50% of industrial chemicals are sold within the Chemicals and Allied Products sector. To give a simple example, chlorine might be sold to another company to make vinyl chloride, which in turn is sold to someone else to make poly(vinyl chloride) plastic, which can be made by another company into a finished plastic product. Some chemicals are exported others are sold to the government for defense and to other industries, especially agriculture, petroleum refining, and paper products. 

The C6-Cn branched, odd and even, linear and internal olefins are used to produce unproved flexible poly (vinyl chloride) plastics. 

The single use of vinyl chloride is in the manufacture of poly(vinyl chloride) plastic, which finds diverse applications in the building and construction industry as well as in the electrical, apparel, and packaging industries. Poly(vinyl chloride) does degrade relatively fast for a polymer, but various heat, ozone, and ultraviolet stabilizers make it a useful polymer. A wide variety of desirable properties can be obtained by using various... 

D 2301 Specification for Vinyl Chloride Plastic Pressure Sensitive Electrical... 

D 3005 Specification of Low Temperature Resistant Vinyl Chloride Plastic Pressure... 

Some unexpectedly complex liquid solid interactions have been detected and studied by ultrasonic impedance measurements (ultrasonic impedometry). Small amounts of water and alcohols have pronounced effects on the physical state of hydrophilic polymers specifically, the high frequency shear modulus and crystallinity index of a poly (vinyl alcohol) film increases with water content to a maximum before normal solution phenomena occur. These effects are attributed to the increased molecular order owing to water hydrogen bonded between polymer chains. The unusual effects of moisture on a novel poly(vinyl chloride)/plasticizer system and on hydrophilic polymers other than poly (vinyl alcohol) are also described. 

PPh3 2-Ethyl-1-hexanol is usually reacted with phthalic anhydride to produce dialkyl phthalic esters that are used as plasticizers to keep poly(vinyl chloride) plastics soft and ftexible. 

Draw both a Lewis structure and a line-bond structure for vinyl chloride, C2H3CI, the starting material from which PVC [poly(vinyl chloride) plastic is made. 

ASTM F 891-90 Standard Specification for Coextruded Poly(Vinyl Chloride) Plastic Pipe with a Cellular Core, 8 pp (Comm F-17)... 

When chloroprene was grafted onto cationic aminated starch, a latex was obtained that imparted wet strength to paper and also served as a pressureless adhesive for wood 2951 Starch dialdehyde when grafted with acrylonitrile, methyl methacrylate, or both, produced a biodegradable filler for poly (vinyl chloride) plastics.2942 Starch xanthates grafted with vinyl monomers were also used to produce additives for reinforced foamed rubber.2944,2945... 

Vinyl chloride Plastic industry Angiosarcoma of the liver... 

The types of polymers in current use are somewhat limited and are mainly poly(dimethyIsiloxane), polyethylene, polytetrafluo-roethylene, poly(methyl methacrylate) and derivatives, poly(ethylene terephthalate), poly(vinyl chloride) [plasticized] and some polyether polyurethane ureas. A large number of other polymers are being studied experimentally. Because of the wide diversity of uses, each of which has very specific requirements, it is not possible for any single polymer to be the only material used in medical applications. In the past, medical applications were usually attempted with a commercial grade of a polymer, but this... 

Compatibility of Plasticizers in Poly(Vinyl Chloride) Plastics Under Compression," ASTM D 3291—74, 1980. 

Bask Silicate White Lead. [Akrochem] General stabilizer to vinyl chloride plastics paint pigment... 

Vinyl chloride Plastics/organic compounds synthesis Systemically toxic/carcinogenic... 

Valenta, J. N., Sun, L., Ren, Y, and Weber, S. G, Solvatochromic study of poly(vinyl chloride) plasticizers and their solutions in chloroform application to phenobarbital partitioning and molecular recognition of phenobarbital. Analytical Chemistry, 69, 3490, 1997. 

It is seen from Figure 3.52b that the dielectric strength increases rapidly with decreasing thickness of the sample. A rule of thumb is that the dielectric strength varies inversely with the 0.4 power of the thickness. For example, if the dielectric strength of poly(vinyl chloride) plastic is 375 V/mil in a thickness of 0.075 in., it would be 375(75/15) or about 700 V/mil in foils only 15 mils thick. The fact that thin foils may have proportionally higher dielectric strength is utilized in the insulation between layers of transformer turns. 

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