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Vinyon is a synthetic fiber made from polyvinyl chloride. In some countries other than the United States, vinyon fibers are referred to as polyvinyl chloride fibers. It can bind non-woven fibers and fabrics. It was invented in 1939. It has the same health problems associated with chlorinated polymers.
Questions that require lower cognitive levels to answer are seen as injurious, even though questioning holds a major role in classroom interaction. This type of question does not encourage participation nor does it stimulate student thinking. Studies by Barnes (1983), Fischer and Grant (1983) as cited by Blanchette (2007) [12] have found that ...
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 ).
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")
Vinyl chloride is produced by dehydrochlorination of 1,2-dichloroethane. [1] Due to their high utility, many approaches to vinyl halides have been developed, such as: reactions of vinyl organometallic species with halogens; Takai olefination; Stork-Zhao olefination with, e.g., (Chloromethylene)triphenylphosphorane - a modification of the Wittig ...
High-level and low-level, as technical terms, are used to classify, describe and point to specific goals of a systematic operation; and are applied in a wide range of contexts, such as, for instance, in domains as widely varied as computer science and business administration.
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