Vinyltoluene properties

Vinyltoluene (VT) is a mixture of meta- and i ra-vinyltoluenes, typically in the ratio of 60 40. This isomer ratio results from the ratio of the corresponding ethyltoluenes in thermodynamic equiHbrium. Physical properties and chemical analysis of a typical vinyltoluene product are shown in Tables 7 and 8, respectively. Vinyltoluene monomer is produced by Dow Chemical Company and Fina Oil Chemical Company. The worldwide consumption is estimated to be approximately 100,000 t/yr. 

Vinyltoluene, comprising a mixture of ca 33% para- and 67% y /i7-methylstyrene, has been marketed for ca 45 yr by Dow Chemical Company and also by Cosden. However, the performance properties of the polymers prepared from the para isomer are not only superior to those of the polymer prepared from the typical mixed isomers, but are generally superior to those of polystyrene (60). This advantage, coupled with a raw material cost advantage over styrene, suggests that i ra-methylstyrene may displace significant amounts of styrene, currendy a 3.2 x 10 t/yr domestic market. 

OFM are viscous liquids, or readily fusible resinTike substances, capable (in the presence of intiators or upon irradiation) of three-dimensional radical copolymerization with several active monomers (styrene, vinyltoluene, methylmethacrylate and others). The properties of the network copolymers formed largely depend on the chemical nature of the reagents and the copolymerization conditions. Hardening of OFM may be carried out at room temperature, or even lower, using mixtures... 

Similar to the case of styrene, the copolymers of alkylstyrenes and arylstyrenes are common. The copolymerization is done for the same purposes as for polystyrene, namely to improve/modify certain properties. Copolymerization with divinylbenzene is probably the most frequently utilized. This copolymerization improves mechanical resistance, decreases solubility, and improves thermal resistance. For example, thermal decomposition of poly(vinyltoluene-co-divinyl benzene) 10-50% DVB starts at a higher temperature than that of poly(vinyl toluene). The decomposition at 560° C generates C1-C4 hydrocarbons, benzene, toluene, ethylbenzene, styrene, ethyltoluene, a-methylstyrene, vinyltoluene, divinylbenzene, naphthalene, and ethylstyrene, with a distribution that varies with copolymer composition [71, 118]. 

The nonacrylic monomer styrene is used as a reactive solvent in the polymerisation of coating systems on the basis of unsaturated polyesters. Styrene has a penetrating and unpleasant odour and a strong irritant effect. In spite of this substitute, products such as 2-phenyl-l-propene (a-methylstyrene), n-vinylpyrrolidone and vinyltoluene have not become established owing to their clearly inferior application properties. 

The Pd-catalyzed coupling reaction of an aryl halide and olefin is a very efficient and practical method for making C—C bonds. The Heck alkenylation of aryl bromides with ethylene was used by Dow Chemical to make high-purity 2- and 4-vinyltoluenes, which are of interest as co-monomers in styrene polymers [159]. The monomer, o-vinyltoluene (99), has a low toxicity and an attractive co-monomer for styrene polymers. o-Vinyltoluene improved heat distortion properties of styrene and polymerization rate. It also minimized color formation or cross-linking and it was difficult to make by other routes [159]. Catalyst turnover, rate, and lifetime were significantly improved. 

Polyacrylates as binders consist of copolymers of acrylate and methacrylate esters. Other unsaturated monomers (e.g., styrene and vinyltoluene) may also be incorporated, but usually to a lesser extent. Copolymers formed exclusively from acrylates and/or methacrylates are termed straight acrylics. The comonomers differ as regards the alcohol residues of the ester group, which also allow incorporation of additional functional groups. Choice of suitable monomers allows wide variation of the physical and chemical properties of the resulting polymer. Hydrophilicity, hydrophobic-ity, acid base properties as well as can be adjusted resins containing hydroxyl, amine, epoxy, or isocyanate groups can also be produced. 

DIN 53183 defines an alkyd resin as follows Alkyd resins are synthetic polyester resins produced by esterifying polyhydric alcohols with polybasic carboxylic acids. At least one of the alcohols must be trihydric or higher. Alkyd resins are always modified with natural fatty acids or oils and/or synthetic fatty acids. In order to obtain particular application technology properties, alkyd resins may be additionally modified with compounds such as resin acids, benzoic acid, styrene, vinyltoluene, isocyanates, acrylic, epoxy, or silicone compounds. ... 

Properties Styrene Vinyltoluene 2-Hydroxyethyl methacrylate Glycerol a-allyl ether... 

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