Vinyltoluenes, preparation

Hydrocarbon resins (qv) are prepared by copolymerization of vinyltoluene, styrene, and a-methylstyrene in the presence of a Eriedel-Crafts catalyst (AlCl ). These resins are compatible with wax and ethylene—vinyl acetate copolymer (197). 

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. 

Seven polystyrene latexes prepared with persulfate initiator and bicarbonate buffer were characterized to demonstrate the efficacy of this method (6). Three were monodisperse latexes prepared using conventional emulsifiers four were prepared using sodium styrene sulfonate or sodium vinyltoluene sulfonate as canan-omeric emulsifiers. Each latex was subjected to serum replacement with... 

The application of ethylene in Heck reactions often shows different activities from other alkenes, because of Wacker-type side reactions. It was found, however, that iodo- and acceptor-substituted bromoarenes are cleanly converted in aqueous media to the corresponding styrenes utilizing a palladium-TPPMS complex [13], Furthermore, high purity o- and p-vinyltoluenes were prepared on a large scale (in... 

Similarly />-triphenylleadstyrene can be prepared and homo-or copolymerized (with vinyltoluene) [4]. 

In the pioneering work of Krieger and co-workers, monodisperse latices were prepared with mixtures of anionic and nonionic surfactants in the aqueous phase. Their mixtures of styrene (or vinyltoluene), water, surfactants, and initiator were stirred in a resin flask using a very large, specially designed stainless steel paddle. Stirring was at a very modest rate [76]. 

Two other triblock polymers were prepared in cyclohexane. Run no. 13 used polyisoprene in place of polybutadiene as the center block. Run no. 14 used vinyltoluene in place of styrene in the SAMS end block copolymer. The polymerization conditions and results are shown in Table 5. 

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