Vinylbenzene

A process of polymerization of isomerized a-pinene or turpentine with vinylbenzenes has been disclosed (105). a-Pinene or turpentine is isomerized by flash pyrolysis at 518 5° C in a hot tube reactor to yield a mixture of predominantly dipentene and i7t-alloocimene... 

A partially cross-linked, isobutylene—isoprene—divinylbenzene terpolymer containing some unreacted substituted vinylbenzene appendages is commercially available from Polysar Division, Bayer AG. Because of the residual reactive functionality, it can be cross-linked by peroxides that degrade conventional butyl mbbets. It is employed primarily in the manufacture of sealant tapes and caulking compounds (31). 

Chemical Designations - Synonyms Phenethylene Phenylethylene Styrol Styrolene Vinylbenzene Chemical Formula C6HjCH=CH2. 

UV irradiation of hexafluorobenzene with indene or cycloalkenes gives high yields of 2+2 adducts, which undergo further intramolecular cycloaddition to form hexafluoropolycycloalkanes [754] (equation 38) Photolysis of fluormated deriva tives of vinylbenzenes afford benzocyclobutenes, whereas allyl benzenes yield Dewar benzene-type products [755]... 

Vinyl-benzol, n. vinylbenzene. -cyaniir, n. vinyl cyanide, acrylonitrile, -harz, n. vinyl resin. 

Styrene (vinylbenzene) is a liquid (b.p. 145.2°C) that polymerizes easily when initiated by a free radical or when exposed to light. The 1998 U.S. production of styrene was approximately 11 billion pounds. 

Styrene (Phenyl Ethylene, Ethenylbenzene or Vinylbenzene). HsCH2,mw 104.16,... 

Resin bead polymer composition Either acrylic resins or, more generally, styrene (vinylbenzene, VB) are cross-linked with typically 4 to 20% divinylbenzene (DVB) in a copolymer network or matrix. 

Common chemistries include tannins and lignins but also more modem polyacrylates and derivatives, which often act as carriers for specific functional groups and provide novel chemistry molecules. The polyacrylates may also be copolymerized, perhaps with maleates [maleic anhydride, cis-butenedioic anhydride (OCOCHrCHCO) is the usual starting point material], styrene (vinylbenzene, phenylethylene,... 

Chain reactions carried out on one type of monomer give rise to homopolymers when using two types of monomer the situation is more complicated. For example, polymerising mixtures of vinyl chloride with acrylate esters gives rise to a range of molecules, the first of which are relatively rich in acrylate molecules formed later, when the amount of acrylate monomer is relatively depleted, are richer in vinyl chloride. In a number of instances, reactions of this kind can be used to prepare polymers containing monomers which will not homopolymerise, e.g. maleic anhydride and stil-bene (vinylbenzene). 

In addition to the crosslinks already mentioned, there exist a number of possibilities for secondary reactions, so that the final resin may consist of a number of crosslinks whose origin is not immediately clear. For example, this is evidence that some resins contain units that are effectively derivatives of stilbene (vinylbenzene), implying that there are units in the cured resin corresponding to that illustrated (4.1). 

The nonionic monomer can be acrylamide, N,N-dimethylacrylamide, N-vinyl-2-pyrrolidone, N-vinyl acetamide, or dimethylamino ethyl methacrylate. Ionic monomers are AMPS, sodium vinyl sulfonate, and vinylbenzene sulfonate. The terpolymer should have a molecular weight between 200,000 to 1,000,000 Dalton. 

N-vinyl acetamide, or dimethylamino ethyl methacrylate, 2-acrylamido-2-methylpropane sulfonic acid, sodium vinyl sulfonate, and vinylbenzene sulfonate... 

One of the monomers used in the manufacture of styrene-butadiene mbber. It is vinylbenzene, a liquid boiling at 146 °C and having the formula... 

Synonym phenylethene, styrol, styrolene cinnamene, cinnamol, phenylethylene, vinylbenzene, ethenylbenzene... 

The aryl rings of acetophenone and methyl benzoate are preferentially hydrogenated, with only minor reduction of the substituents. In contrast, hydrogenation of nitrobenzene, under essentially the same conditions, produces aniline and nitro-cyclohexane in ca. 9 1 ratio, with an overall conversion of >79%. This observation has additional significance when compared with the hydrogenation of the nitro derivative of vinylbenzene (Table 11.25). In all cases, it is the C=C bond which is hydrogenated and, only after a prolonged reduction time, is 1-nitro-2-phenylethene completely reduced to the aminoethane [4],... 

Synonyms Vinylbenzene phenylethylene styrene monomer cinnamene... 

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