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While choosing a liquid phase for suspension polymerization, low viscosity, high thermal conductivity and low-temperature variation of viscosity are generally preferred. The primary advantage of suspension polymerization over other types of polymerization is that a higher degree of polymerization can be achieved without monomer boil-off.
With the aid of spectroscopic techniques such as NMR, it is possible to pinpoint the composition of a polymer in terms of the percentages for each triad. [ 10 ] [ better source needed ] Polymers that are formed by free-radical mechanisms, such as polyvinyl chloride are usually atactic.
Polyvinyl chloride is formed in flat sheets in a variety of thicknesses and colors. As flat sheets, PVC is often expanded to create voids in the interior of the material, providing additional thickness without additional weight and minimal extra cost (see closed-cell PVC foamboard ).
The mixture of polyvinyl chloride and polyurea has a good bond strength. Closed-cell PVC foam takes solid shape due to its linear structure. However, due to this structure, it is more brittle than open-celled PVC foam. It is available in densities varying from 3 to 25 pounds per cubic foot (0.048 to 0.400 g/cm 3). [3] It has a low flammability ...
Vinyl chloride is an organochloride with the formula H 2 C=CHCl. It is also called vinyl chloride monomer (VCM) or chloroethene. It is an important industrial chemical chiefly used to produce the polymer polyvinyl chloride (PVC). Vinyl chloride is a colourless flammable gas that has a sweet odor and is carcinogenic.
Vinyl polymers are subject of several structural variations, which greatly expands the range of polymers and their applications. With the exception of polyethylene, vinyl polymers can arise from head-to-tail linking of monomers, head-to-head combined with tail-to-tail, or a mixture of those two patterns. Additionally the substituted carbon center in such polymers is stereogenic (a "chiral center")
Plastisol. A plastisol is a colloidal dispersion of small polymer particles, usually polyvinyl chloride (PVC), in a liquid plasticizer.When heated to around 180 °C (356 °F), the plastic particles absorb the plasticizer, causing them to swell and fuse together forming a viscous gel.
Polyvinyl acetate used further for polyvinyl alcohol is manufactured by radical polymerization in methanol solution. Liquid polybutadienes are made by anionic or radical polymerization in hydrocarbon solutions. Butyl rubber (IIR) by low temperature cationic copolymerization of isobutylene with isoprene in ethylene or methylchloride solution.