Polyvinyl compounds

Polyvinyl compounds are produced either by the polymerization of vinyl compounds CH2=CHX or by polymer analog reactions on polyvinyl compounds. The derivatives of poly(vinyl alcohol) -%CH2—CH(OHH- , poly(vinyl halides) -f-CH2—CHHal and poly-(vinyl amines) -%CH2—CH(NRiR2)- are of particular commercial importance. In contrast to these, poly(vinyl sulfides) -f-CH2—CH(SR)- are only of academic interest. Vinyl alcohol is unstable, since it transforms into acetaldehyde on formation. Therefore, poly(vinyl alcohol) is produced from poly(vinyl acetate). 

From acetylene and acetic acid. The direct addition of acetylene to acetic acid occurs in the liquid or the gas phase. The liquid-phase reaction is carried out at 75-80°C with HgS04 catalyst. The vinyl acetate must be removed from the reaction mixture as quickly as possible otherwise too much ethylidene diacetate will result. However, the formation of the diester can be inhibited by the addition of HgS04/BF3/HF. This method has the commercial disadvantage that the residual deposits of poly(vinyl acetate), metallic mercury, etc., produced can only be removed by burning. The gas-phase method proceeds at 180°C with zinc acetate as catalyst. Only 5-10% of vinyl acetate can be formed per cycle, since otherwise large amounts of by-products occur. The theoretically possible total yield 

From ethylene and acetic acid. The two known methods differ in the in situ dehydrogenation method. In the first method 

In this method, only a small amount of CH3CHO is produced. 

From acetaldehyde and acetic anhydride. The two basic materials are obtained from butane (butane acetaldehyde - acetic acid - acetic anhydride)  

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Ion exchangers are polymer electrolytes prepared a priori as insoluble solids (salts, acids, bases hydrated, possibly gel-Uke). Their polymer backbone is three-dimensional. Many are polyvinyl compounds (substituted polyethylenes) having the general formula [-CH2-CXH-] , where different substituents X lead to rather different products ... 

Examples are the sulfonating of polyethylene film with chloro-sulfonic acid (60) the sulfonating of sheets of phenolformaldehyde resin (77) the treatment of a film consisting of polystyrene and polyvinylchloride with concentrated sulfuric acid (4) the sulfonating of films consisting of aliphatic vinylpolymers with chlorosulfonic acid (125) the sulfonating of copolymers of a monovinyl- and a polyvinyl compound (30). Also are used copolymers of aromatic monovinyl-compounds and linear aliphatic polyene hydrocarbons (3) copolymers of an unsaturated aromatic compound and an unsaturated aliphatic compound (76), and of reaction products of poly olefines and partially polymerized styrene (173). 

Pure carbon chains. The chains can be unsubstituted (e.g. PE) or contain single or multiple substitutions (polyvinyl compounds). 

Granular anion-exchange resins have been prepared from N-containing C-vinyl heterocyclics, polyvinyl compounds and one or more aliphatic vinyl compounds in an aqueous phase in presence of water-insoluble suspension stabilizers Thus, a mixture of 4-vinylpyridine, ethylacrylate, and p-DVB on polymerization using hydroxylapatite as suspension stabilizer and AIBN as the initiator gives an anion-exchange resin. 

Covering particles of ammonium nitrate with non-hygroscopic layers of polymers, such as polyvinyl compounds. This however should be Uiniied to substances which could not produce harmful influence on the explosive properties of ammonium nitrate and (for underground work) would not give harmful products after detonation, such as chlorine compounds from polyvinyl chloride. 

Vinyl acetate is used in the manufacturing of polyvinyl compounds, resins, glues, polymer adhesives, vinyl copolymers, plastics, and latex paints. 

Use Intermediate, insolubilizing agent for proteins and polyhydroxy materials, cross-linking agent for polyvinyl compounds, shrinkage control agent (textiles). 

Whiteley KS, Heggs TG, Koch H, Mawer RL, Immel W. Polyolefins. In Elvers B, Hawkins S, Schulz G, editors. Plastics, Properties and Testing of Polyvinyl Compounds. 5 th ed. Vol. A21. New York VCH Publishers 1992. p 487 ff. 

For these reasons we conclude that optical resolution of racemates takes place within the cavities formed by the template. Another possibility might be that separation takes place at polymer chain segments that exhibit a preference for one enantiomeric arrangement due to the chirality of the main chain. Although it has been demonstrated quite recently (23,48,49) that polyvinyl-compounds can be optically active due to the chirality of the main chain, this can be excluded for polymerization in the presence of 1 ( ). Additionally, arguments ii, iii, and iv would speak against the participation of chiral chain segments in racemic resolution. 

All vinyl polymers are addition polymers. To differentiate the, the homopolymers have been classified by the substituents attached to one carbon atom of the double bone. If the substituent is hydrogen, alkyl or aryl, the homopolymers are listed under polyolefins. Olefin homopolymers with other substituents are described under polyvinyl compounds, except where the substituent is a nitrile, a carboxylic acid, or a carboxylic acid ester or amide. The monomers in the latter cases being derivatives of acrylic acid, the derived polymers are listed under acrylics. Under olefin copolymers are listed products which are produced by copolymerization of two or more monomers. 

Wulff, G. Dhal, P.K. Chirality of polyvinyl compounds. 6. Unusual influences of the comonomer structures on the chiroptical properties of optically active vinyl copolymers... 

Phenolic resins have been developed to a highly versatile degree as lacquer and paint bases. Pure Novolak is only soluble in polar solvents such as acetone, alcohol, low esters, etc. However, the market potential of alcohol-based lacquers is limited, and such lacquers are too brittle for many uses. For this reason, so-called plasticized and elasticized phenolic resins ( substituted phenolics ) were developed. Plastification is achieved either by partial etherification (e.g., with t-butyl alcohol), esterification (e.g., with fatty acids), or both etherification and esterification (e.g., with adipic acid and trimethylol propanol). These plasticized phenolic resins have increased elasticity, are soluble in aromatics, are compatible with polyvinyl compounds and fatty acids, and are suitable for use as stoving enamels. 

Hallensleben, M. L. (2005). Polyvinyl compounds, others. In Ullmann s encyclopedia of industrial chemistry. Wiley-VCH. 

One problem that has been studied in detail with various polymers is the influence of the tacticity on the optical rotation of optically active polyvinyl compounds and polyolefins. Only those studies in which polymer analog reactions were used will be cited here. 

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