Polyvinyl chloride solubilities

Strontium carbonate Polyvinyl chloride Soluble glutinous rice starch Specific gravity=1.30 g/cc Burning rate =1 7 mm/sec... 

Copolymers of vinyl chloride, containing 5 to 40 percent vinyl acetate made by the inclusion of vinyl acetate in the polymerization process, have lower softening points and flow more easily than polyvinyl chloride. They are soluble in ketones, such as acetone, and certain esters for making film from solutions. They are used for phonograph records, rigid clear sheeting, and molding pov... 

The most common backbone structure found in commercial polymers is the saturated carbon-carbon structure. Polymers with saturated carbon-carbon backbones, such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, and polyacrylates, are produced using chain-growth polymerizations. The saturated carbon-carbon backbone of polyethylene with no side groups is a relatively flexible polymer chain. The glass transition temperature is low at -20°C for high-density polyethylene. Side groups on the carbon-carbon backbone influence thermal transitions, solubility, and other polymer properties. 

In suspension polymerization, the monomer is agitated in a solvent to form droplets, and then stabilized through the use of surfactants to form micelles. The added initiator is soluble in the solvent such that the reaction is initiated at the skin of the micelle. Polymerization starts at the interface and proceeds towards the center of the droplet. Polystyrene and polyvinyl chloride are often produced via suspension polymerization processes. 

Figure 22.2 Chemical structure of monomer soluble initiators for polyvinyl chloride a) dilauryl peroxide, b) benzoyl peroxide and c) azobisisobutyronitrile...

Suspension polymerization. In this process, monomers and initiator are suspended as droplets in water or a similar medium. The droplets are maintained in suspension by agitation (active mixing). Sometimes a water-soluble polymer like methylcellulose or a finely divided clay is added to help stabilize or maintain the droplets. After formation, the polymer, is separated and dried. This route is used commercially for vinyl-type polymers such as polyvinyl chloride and polystyrene. 

Glasses exist that fnnction as selective electrodes for many different monovalent and some divalent cations. Alternatively, a hydrophobic membrane can be made semiper-meable if a hydrophobic molecnle called an ionophore that selectively binds an ion is dissolved in it. The selectivity of the membrane is determined by the structnre of the ionophore. Some ionophores are natnral products, such as gramicidin, which is highly specific for K+, whereas others such as crown ethers and cryptands are synthetic. Ions such as, 1, Br, and N03 can be detected using quaternary ammonium cationic surfactants as a lipid-soluble counterion. ISEs are generally sensitive in the 10 to 10 M range, but are not perfectly selective. The most typical membrane material used in ISEs is polyvinyl chloride plasticized with dialkylsebacate or other hydrophobic chemicals. 

Intractable polymers, such as polyvinyl chloride (PVC), may be flexibilized, to some extent, by the formation of copolymers, such as the copolymers of vinyl chloride and vinyl acetate or octyl acrylate, or by the addition of nonvolatile low-molecular-weight compounds (plasticizers) having solubility parameters similar to those of the polymer. Thus PVC is plasticized by the addition of dioctyl phthalate. The flexibility of these products is proportional to the amount of plasticizer added. Copolymers, such as the vinyl chloride-vinyl acetate copolymer, require less plasticizer to obtain the same degree of flexibility. 

In addition to the polymer, copolymers of vinyl chloride with other vinyl monomers are important commercial plastics. Copolymers with vinyl acetate, which is produced from acetylene and acetic acid, are widely used in sheeting, surface coating, and filaments, being less brittle and more readily soluble in organic solvents than is pure polyvinyl chloride. Copolymers with acrylonitrile are also of importance for the production of... 

Polyvinyl Halides. Chlorinated Polyvinyl Chloride It was produced in Germany up to three decades ago, but this was primarily a 1,1-disubstituted product of increased solubility for dry-spinning of fibers. Goodrich has developed a light-activated suspension chlorination process which produces 1,2-dichlorinated structures of increased hot strength, thermal stability, and flame resistance. 

Pure polyvinyl chloride alone It a rigid plastic of high volume resistivity. Addition of monomeric liquid plasticizer makes It flexible but lowers volume resistivity seriously. This loss of volume resistivity was not prevented by pre-purification of commercial resin and plasticizer, though It could be worsened by addition of Ionic soluble Impurities. Volume resistivity was surprisingly Increased by heat aging. It was not improved by use of polymeric liquid plasticizers, nor even, surprisingly, by use of nitrile rubber as plasticizer. Flexlblllzatlon without serious loss of volume resistivity was best achieved by internal plasticization by copolymerization with 2-ethylhexyl acrylate. Further studies are needed to explain these observations and to optimize the use of Internal plasticization In this way. 

At first glance the use of solid nitrile rubber in place of liquid plasticizers would appear to improve the volume resistivity of plasticized polyvinyl chloride somewhat but when the lower plasticizing efficiency of the nitrile rubber is considered, only little improvement remains at equal tensile modulus or hardness. This is difficult to explain in terms of the flow of ions through a liquid plasticizer medium. As we can see, the volume resistivity of nitrile rubber alone is much lower than that of polyvinyl chloride, and the volume resistivity of these blends is simply the resultant of the two components. Actually the same reasoning might well apply to conventional blends of good quality polyvinyl chlorides with good quality liquid plasticizers, in the absence of any added ionic soluble impurities, as we can see from our earlier data. 

In summary, the volume resistivity of polyvinyl chloride plasticized by liquid or elastomeric plasticizers, or internally plasticized by copolymerization, was intermediate between the inherent volume resistivities of the pure components and combined the contributions of each of them. The presence of ionic soluble impurities in liquid plasticizers provided mobile ions which conducted electricity and thus lowered volume resistivity. Copolymerization with 2-ethylhexyl acrylate provided an excellent balance of softness and flexibility with high volume resistivity further studies of internal plasticization by copolymerization are therefore recommended. 

Plates coated with purified soluble antigen. As an alternative to step 7 above, and providing purified soluble antigen is available, 96-well PS or polyvinyl chloride (PVC) plates can be coated with protein, recombinant protein, peptide, or peptide conjugated to a carrier protein Plates are coated as follows... 

To get a better insight into the chlorination reaction, we wanted to avoid a heterogeneous process. Instead of polyethylene or polypropylene, we used polyisobutene, which is soluble in carbon tetrachloride, as are its chlorination products. In addition, we were interested in the structure and properties of the chlorinated products, especially in comparison with polyvinyl chloride (PVC) and vinyl chloride/isobutene (VC/IB) copolymers. 

The formation of coagulum is observed in all types of emulsion polymers (i) synthetic rubber latexes such as butadiene-styrene, acrylonitrile-butadiene, and butadiene-styrene-vinyl pyridine copolymers as well as polybutadiene, polychloroprene, and polyisoprene (ii) coatings latexes such as styrene-butadiene, acrylate ester, vinyl acetate, vinyl chloride, and ethylene copolymers (iii) plastisol resins such as polyvinyl chloride (iv) specialty latexes such as polyethylene, polytetrafluoroethylene, and other fluorinated polymers (v) inverse latexes of polyacrylamide and other water-soluble polymers prepared by inverse emulsion polymerization. There are no major latex classes produced by emulsion polymerization that are completely free of coagulum formation during or after polymerization. 

Many of the remarks made in the previous section concerning fibres can be applied to the analysis of plastics. Some polymers are soluble in organic solvents and samples may be prepared for direct aspiration into a flame in this way, e.g. MIBK is a suitable solvent for polyesters, polystyrene, polysiloxanes, cellulose acetate and butyrate dimethyl formamide for polyacrylonitrile, dimethyl acetamide for polycarbonates and polyvinyl chloride cyclohexanone for polyvinyl chloride and polyvinyl acetate formic acid for polyamides and methanol for polyethers. These organic solutions may alternatively be injected into a graphite furnace. Otherwise, polymers may be wet or dry ashed and the resultant ash dissolved in acid. An approach which is attracting increasing interest is the direct insertion of solid samples into a graphite furnace. 

Heintz, A. Lichtenthaler, R. N. Prausnitz, J. M., "Solubilities of Volatile Solvents in Polyvinyl Acetate, Polyvinyl Chloride, and Their Random Copolymers," Ber. Bunsenges. Phys. Chem., 83, 926 (1979). 

A similar situation occurs with vinyl chloride (VC) for a very different reason. Vinyl chloride is very soluble in water, but polyvinyl chloride (PVC) is not soluble in its own monomer. VC does swell PVC, and for that reason, there is a driving force for VC transport across the aqueous phase in macroemulsion polymerization. This transport is aided by the fact that VS is very soluble in water. However, this is one macro emulsion system that might greatly benefit from the miniemulsion synthesis route. 

Vinyl Derivatives. Vinyl derivatives are water-soluble polymers and include PVA, PVP, polyvinyl (or polyacrylic) acid, and polyvinyl chloride. 

Veith, G.D., Macek, K.J., Petrocelli, S.R., Carroll, J. (1980) An evaluation of using partition coefficients and water solubility to estimate bioconcentration factors for organic chemicals in fish. In Aquatic Toxicology, pp. 116-129. ASTM STP 707, Eaton, J.G., Parrish, P.R., Hendricks, A.C., Eds., pp.116-129. Am. Soc. for Testing and Materials, Philadelphia, Pennsylvania. Verhoek, P.H., Marshall, A.L. (1939) Vapor pressures and accommodation coefficients of four non-volatile compounds. The vapor pressure of tri-ra-cresyl phosphate over polyvinyl chloride plastics. J. Am. Chem. Soc. 61, 2737-2742. 

However, a 2% v/v aqueous solution in a polyethylene container, stored at 20°C, may lose up to 15% of its benzyl alcohol content in 13 weeks. Losses to polyvinyl chloride and polypropylene containers under similar conditions are usually negligible. Benzyl alcohol can damage polystyrene syringes by extracting some soluble components. ... 

This substance has extensive lipid solubility and is absorbed immediately by the skin. Additionally, DMM is able to penetrate many materials including plastic and rubber compounds such as latex, polyvinyl chloride, and neoprene in a matter of seconds. In permeability tests, a Silver Shield glove of a flexible, plastic-laminate, offered skin protection from DMM for 4h. This chemically resistant glove, when worn under an outer glove that is resistant to abrasion and tears, may provide limited protection for direct handling of DMM. 

Sentry [Dow], 1. TM for propionic acid. 2. TM for high purity grades of Carbowax polyethane glycol, polyox water-soluble polymers, and polyvinyl chloride. Solvent for flavors and colors. 

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