Polyvinylidene chloride , surface

Colloidal carbon was formed by the slow pyroloysis of polyvinylidene chloride. Surface oxidation occurs during subsequent storage in air. By heating at elevated temperatures, the following gases are evolvedt (heats of immersion were also measured after the different thermal pretreatments) ... 

Another important addition polymer is polyvinylchloride (PVC), which is tough and easily molded. Floor tiles, shower curtains, and pipes are most often made of PVC, shown in Figure 12.30. The addition polymer polyvinylidene chloride (trade name Saran), shown in Figure 12.31, is used as plastic wrap for food. The large chlorine atoms in this polymer help it stick to surfaces such as glass by dipole—induced dipole attractions, as we saw in Section 7.1. 

You may need to play around with the drops for a while in order to see the differing affinities that the bag and wrap have for water. One way to do this is to tape the polymers side by side stretched out on a sturdy piece of cardboard. Tilt the cardboard to various angles, testing for the speed with which water drops roll down the incline on the two surfaces. Ultimately, you should find that the drops roll more slowly on the wrap (polyvinylidene chloride) than on the bag (polyethylene terephthalate). The source of this greater stickiness in the wrap is the fairly large chlorine atoms of the polyvinylidene chloride. 

The term film is also applied to sheets of cellophane, polyethylene, polyvinylidene chloride, etc., used for wrapping and packaging of food products, meats, and poultry (especially shrink films that are stretched before application). These function as a moisture vapor harrier. Plaslic lilms are also used as slip surfaces in concrete structures such as airstrips, ice rinks, and highways. Photographic film is made from cellulose acetate. 

Savoury bagged snacks (such as Twiglets, pork scratchings, Bombay mix, etc.) Polypropylene/aluminium/printing inks/polypropylene laminate Printed (external surface) polypropylene Polyethylene/printing inks/polyvinylidene chloride laminate Polypropylene/printing inks/polypropylene laminate... 

Moreno-Castilla investigated the adsorption behavior of mono-substituted phenols of different solubilities on activated carbons obtained from an original and demineralized bituminous coal. The adsorption capacity of the activated carbon was found to depend on the surface area and the porosity of the carbon, the solubility of the phenolic compound, and the hydrophobicity of the substituent. The relative affinity of the phenolic compound toward the carbon surface was related to the donor-acceptor complexes formed between the basic sites on the carbon surface and the organic ring of the phenol. The adsorption was also influenced by the pH of the solution. Marsh and Campbell observed that the adsorption of p. nitrophenol at low concentrations on polyfurfuryl alcohol and polyvinylidene chloride activated carbons was extremely sensitive to the microporous structure of these carbons and showed adsorption isotherms similar to those of nitrogen or carbon dioxide. The adsorption of p.nitrophenol was so strong at low clc values that the adsorption... 

For this approach, the microtluidic channel is microma-chined into glass or silicon. On the bonding surface of the chip, close to the channel rim, metallic (aluminum) heater elements are patterned. The thermoplastic counterpart is a Mylar (polyethylene) foil laminated with a PVDC (polyvinylidene chloride) contact layer. The two parts are pressed together while maintaining a temperature of 150-200 °C at the aluminum-PVDC interface to locally melt the PVDC [17]. 

These effects are seen in Figures 2.18 and 2.19 for the carbonization of two polymeric, non-fusing solids which produce carbon (isotropic) of the same shape and size (about) as the parent material. The polyvinylidene chloride (PVDC) yields a carbon of surface area of about 1200 m g at 1300°C, whereas the carbon from polyfurfuryl alcohol (PFA) does not have this temperature stability and maximizes at about 750 "C giving a surface... 

Equations have been devised to simulate adsorption processes over surfaces and in porosity and which contain the term (mmolg ) as a measure of monolayer coverage. Figure 4.4 contains plots of surface areas (apparent) of a series of activated carbons (from polyvinylidene chloride (PVDC)) against extent of activation (bum-off (wt%)) using... 

If the seed latex particles can barely be swollen by the second-stage monomer and a water-soluble initiator is used, then the subsequent seeded emulsion polymerization will be localized near the particle surface layer. Thus, the postformed polymer tends to form a surface layer around the seed latex particle. An example of this kind of morphological structure of latex particles is the seeded emulsion polymerization of methyl methacrylate in the presence of a polyvinylidene chloride seed latex. On the other hand, free radical polymerization can take place inside the seed latex particles. In this manner, various morphological structures of latex particles such as the perfect core/shell, inverted core/shell, dumbbell-shaped, and occluded structures can be achieved, depending on various physical parameters and polymerization conditions. 

Bansal et al. " combined desorption and base neutralization techniques for investigating the acidic surface groups on several polymer carbons. The base neutralization capacity using sodium hydroxide was found to be almost exactly equivalent to the amount of CO2 evolved on evacuation in the case of polyvinylidene (PVDC), polyvinyl chloride... 

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