Pentene Vinyl chloride

Investigation of the kinetics of the reaction of 4-chloro-2-pentene, an allylic chloride model for the unstable moiety of polyfvinyl chloride), with several thermal stabilizers for the polymer has led to a better understanding of the stabilization mechanism. One general feature of the mechanism is complexing of the labile chlorine atom by the metal atom of the stabilizer. A second general feature is substitution of the complexed chlorine atom by a ligand (either carboxylate or mercaptide) bound to the metal. Stabilization requires that the new allylic substituent (ester or sulfide) be more thermally stable than the allylic chlorine. The isolation of products from stabilizer-model compound reactions supports the substitution hypothesis of poly(vinyl chloride) stabilization. 

The reaction half-time for 4-chloro-2-pentene, the allylic chloride model, with dibutyltin -mercaptopropionate is about 1/20 that for 2-chloro-2-methylbutane, a tert-chloride model, with the same stabilizer. This result supports the choice of an allylic chloride as the most important unstable functionality of poly (vinyl chloride). 

Allylic Chloride vs. tert-Chloride Reactivity. There is some question in the literature as to whether the allylic chloride moiety or ferf-chloride group is more responsible for the thermal instability of poly (vinyl chloride) (I, 2). To shed some light on this problem we compared the relative reactivities at 100 °C. in chlorobenzene of 4-chloro-2-pentene and 2-chloro-2-methylbutane with dibutyltin -mercaptopropionate. Data are summarized in Table I. The half-time for the reaction of the allylic chloride with the stabilizer mercaptide group was less than 15 minutes, whereas the half-time for the tert-chloride was nearly 20 times longer. The greater reactivity of the allyl chloride suggests that it is the more important functionality in polymer degradation. However, these results on rates of chlorine substitution are not necessarily an exact measure of thermal instability. 

Continuous homogeneous catalysis is achieved by membrane filtration, which separates the polymeric catalyst from low molecular weight solvent and products. Hydrogenation of 1-pentene with the soluble pofymer-attached Wilkinson catalyst affords n-pentane in quantitative yield A variety of other catalysts have been attached to functionalized polystyrenes Besides linear polystyrenes, poly(ethylene glycol)s, polyvinylpyrrolidinones and poly(vinyl chloride)s have been used for the liquid-phase catalysis. Instead of membrane filtration for separating the polymer-bound catalyst, selective precipitation has been found to be very effective. In all... 

In small pore zeolite systems, the polymerization of propylene (118), isobutylene (120), vinyl chloride (121), and styrene (121) over Linde 5A, the polymerization of propylene and isobutylene over chabazite (19), and the double bond isomerization of 2-methyl-l-pentene over Linde 5A (122) have been reported. Since most of these reactants and the products derived from them cannot pass through the 4-5 A entry pores, it is assumed that these reactions occurred on the external surface of the zeolite. 

Poly(4-methyl-l-pentene) 298 15.3 Vinyl acetate/vinyl chloride copolymer ... 

A simple synthesis of a glycoside of DL-daunosamine has been devised by Matsumoto and his co-workers. In this approach 1-chloro-l, 4-hexadiene-3-one (77, obtained from crotonyl chloride and vinyl chloride) was converted into 1,1-ethylenedioxy-4 -hexen-3-one (78). cw-Hydroxylation of 78 afforded threo-A o-lon (79). Oximation of 79 and reduction of the oxime gave a single stereoisomeric aminodiol (80) which, after treatment with methanolic hydrogen chloride, yielded methyl a-DL-daunosaminide (74, R = H, R = Me) in 84% yield. Makin and co-workers described two methods leading to both stereoisomeric 2-deoxy-DL-pentoses in the form of their diethyl acetals. In the first method, the readily available 1,l-diethoxy-3-penten-5-ol (81) was directly cri-hydroxylated furnish-... 

Mesityl oxide[141-79-7] (4-methyl-4-penten-2-one) has a strong, peppermint-like odor. It is insoluble in water, but miscible with organic solvents. It has a good solvency for cellulose nitrate, vinyl chloride and vinyl ether copolymers, polyacrylates, and many resins. 

COOH -> CO C C CrC C6H5COCH2CH2CH = CH2 A soln. of benzoic acid in tetrahydrofuran added at room temp, to a soln. in the same solvent of vinylmagnesium chloride prepared from Mg and gaseous vinyl chloride, agitated 4 hrs. at room temp. 5-oxo-5-phenyl-l-pentene. Y 84%. F. e. s. K. Suga et al.. Synthesis 1970, 189. 

Measurements of Brillouin scattering using a Fabry-Perot interferometer have been made on poly(methyl methacrylate) and poly(vinyl chloride) as a function of temperature through the glass transition (175). Only longitudinal measurements were obtained with this arrangement shear waves could not be detected. Improved measurement methods using multiple-pass Fabry-Perot interferometry have been demonstrated for polystyrene (176), poly(4-methyl-l-pentene) (177), and several other amorphous polymers (178). 

Figure 1 Polymer interpretation chart. PAI, polyamideimide PC, polycarbonate UP, unsaturated polyester PDAP, diarylate phtalate resin VC-VAc, vinyl chloride-vinyl acetate copolymer PVAc, polyvinyl acetate PVFM, polyvinyl formal PUR, polyurethane PA, polyamide PMA, methacrylate ester polymer EVA, ethylene-vinyl acetate copolymer PF, phenol resin EP, epoxide resin PS, polystyrene ABS, acrylonitrile-butadiene-styrene copolymer PPO, polyphenylene oxide P-SULFONE, poly-sulfone PA, polyamide UF, urea resin CN, nitrocellulose PVA, polyvinyl acetate MC, methyl cellulose MF, melamine resin PAN, polyacrylonitrile PVC, polyvinyl chloride PVF, polyvinyl fluoride CR, polychloroprene CHR, polyepichlorohydrin SI, polymethylsiloxane POM, polyoxy-methylene PTFE, polytetrafluoroethylene MOD-PP, modified PP EPT, ethylene-propylene terpolymer EPR, ethylene-propylene rubber PI, polyisoprene BR, butyl rubber PMP, poly(4-methyl pentene-1) PE, poly(ethylene) PB, poly(butene-l). (Adapted from Ref. 22, p. 50.)...

Particular studies of the IR spectra of polymers include isotactic poly(l-pentane), poly(4-methyl-l-pentene), and atactic poly(4-methyl-pentene) [18], chlorinated PE [19], aromatic polymers including styrene, terephthalic acid, isophthalic acid [20], PS [21, 22], styrene-glycidyl-p-isopropenylphenyl ether copolymers [23], styrene-isobutylene copolymers [24], vinyl chloride-vinyl acetate-vinyl fluoride terpolymers [25], vinyl chloride-vinyl acetate copolymers [26], styrene copolymers [27], ethylene-vinyl acetate copolymers, graft copolymers, and butadiene-styrene [28] and acrylonitrile-styrene copolymers [29]. 

Other ethylene copolymers that have been studied include those with vinyl alcohol [64], acrylates [65] tetrafluoroethylene [66], 4-methyl pentene [67, 68], propylene - vinyl chloride [69], ethylene vinyl cyclohexane [70] and ethylene - vinyl acetate [71]. 

Ethylene-propylene Ethylene-propylene 4-mediyl-isopentene-1 -pentene Butene-propylene 4-methylpentene-1 -pentene Propylene-butene Propylene-vinyl chloride... 

Indeed, simple monomers, snch as styrene, ethylene, propylene, hexene, vinyl chloride, acrylonitrile and caprolactam, nsnally do occur in the corresponding polymers. In addition to unreacted monomer, any non-polymerisable impnrities in the original monomer feed to the polymerisation conld occur in the final prodnct. Thns, styrene monomers can contain low concentrations of numerous saturated and nnsatnrated hydrocarbons, ethyl benzene being particnlarly prevelent and these, particnlarly the saturated compounds which do not polymerise, will occur in the finished polymer and have implications in the nse of the polymer food packaging. It is not nnknown for compounds as toxic as benzene to occnr at very low concentrations, nsnally less than 10 parts per million in styrene monomer, and this could, therefore, also occur in the polymer. For foodgrades of polystyrene, the monomer content is nsnally nowadays limited to 0.2% maximum. Acrylonitrile monomer may be fonnd in amonnts up to 0.1 % in finished polymer, whilst negligible amounts of monomer are fonnd in polyamide and polymethyl-1-pentene. With thermosets, phenol and formaldelyde are likely to be found even in the most carefully manufactured grades. 

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