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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")
Acrylonitrile is produced by catalytic ammoxidation of propylene, also known as the SOHIO process. In 2002, world production capacity was estimated at 5 million tonnes per year, [5] [8] rising to about 6 million tonnes by 2017. [9] Acetonitrile and hydrogen cyanide are significant byproducts that are recovered for sale. [5]
It is a byproduct in the chlorination of propene to make allyl chloride. [5] It is usually obtained as a mixture of the geometric isomers, called (Z)-1,3-dichloropropene, and (E)-1,3-dichloropropene. Although it was first applied in agriculture in the 1950s, at least two biodegradation pathways have evolved.
PAN is soluble in polar solvents, such as dimethylformamide, dimethylacetamide, ethylene and propylene carbonates, and in aqueous solutions of sodium thiocyanate, zinc chloride or nitric acid. [13] Solubility parameters: 26.09 MPa 1/2 (25 °C) are 25.6 to 31.5 J 1/2 cm −3/2. Dielectric constants: 5.5 (1 kHz, 25 °C), 4.2 (1 MHz, 25 °C).Can ...
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.
Butyl rubber has excellent impermeability to gas diffusion, and the long polyisobutylene segments of its polymer chains give it good flex properties. The formula for PIB is: –(–CH 2 –C(CH 3) 2 –) n – The formula for IIR is: It can be made from the monomer isobutylene (CH 2 =C(CH 3) 2) only via cationic addition polymerization.
Polychlorotrifluoroethylene (PCTFE or PTFCE) is a thermoplastic chlorofluoropolymer with the molecular formula (CF 2 CClF) n, where n is the number of monomer units in the polymer molecule. It is similar to polytetrafluoroethene (PTFE), except that it is a homopolymer of the monomer chlorotrifluoroethylene (CTFE) instead of tetrafluoroethene.
In gas-phase and slurry-reactors, the polymer is formed around heterogeneous catalyst particles. The gas-phase polymerization is carried out in a fluidized bed reactor, propene is passed over a bed containing the heterogeneous (solid) catalyst and the formed polymer is separated as a fine powder and then converted into pellets. Unreacted gas is ...