48174-52-3Relevant articles and documents
Catalytic synthesis of styryl-capped isotactic polypropylenes
Huang, Huahua,Cao, Chengang,Niu, Hui,Dong, Jin-Yong
, p. 3709 - 3713 (2010)
Bis-styrenic molecules, 1,4-divinylbenzene (DVB) and 1,2-bis(4-vinylphenyl) ethane (BVPE), were successfully combined with hydrogen (H2) to form consecutive chain transfer complexes in propylene polymerization mediated by an isospecific metallocene catalyst (i.e., rac-dimethylsilylbis(2-methyl-4- phenylindenyl)zirconium dichloride, I) activated with methylaluminoxane (MAO), rendering a catalytic access to styryl-capped isotactic polypropylenes (i-PP). The chain transfer reaction took place in a unique way where prior to the ultimate chain transfer DVB/H2 or BVPE/H2 caused a copolymerizationlike reaction leading to the formation of main chain benzene rings. A preemptive polymer chain reinsertion was deduced after the consecutive actions of DVB/H2 or BVPE/H2, which gave the styryl-terminated polymer chain alongside a metal-hydride active species. It was confirmed that the chain reinsertion occurred in a regio-irregular 1,2-fashion, which contrasted with a normal 2,1-insertion of styrene monomer and ensured subsequent continuous propylene insertions, directing the polymerization to repeated DVB or BVPE incorporations inside polymer chain. Only as a competitive reaction, the insertion of propylene into metal-hydride site broke the chain propagation resumption process while completed the chain transfer process by releasing the styryl-terminated polymer chain. BVPE was found with much higher chain transfer efficiency than DVB, which was attributed to its non-conjugated structure with much divided styrene moieties resulting in higher polymerization reactivity but lower chain reinsertion tendency.
Simultaneous determination of the micro-, meso-, and macropore size fractions of porous polymers by a combined use of fourier transform near-infrared diffuse reflection spectroscopy and multivariate techniques
Heigl,Greiderer,Petter,Kolomiets,Siesler,Ulbricht,Bonn,Huck
, p. 8493 - 8500 (2008)
Fourier transform near-infrared (FT-NIR) diffuse reflection spectroscopy was used in combination with principal component analysis and partial least-squares regression to simultaneously determine the physical and the chemical parameters of a porous poly(p-methylstyrene-co-1,2-bis(p-vinylphenyl) ethane) (MS/BVPE) monolithic polymer. Chemical variations during the synthesis of the polymer material can alter the pore volume and pore area distributions within the polymer scaffold. Furthermore, mid-infrared and near-infrared (NIR) spectroscopic chemical imaging was implemented as a tool to assess the uniformity of the samples. The presented study summarizes the comparative results derived from the spectral FT-NIR data combined with chemometric techniques. The relevance of the interrelation of physical and chemical parameters is highlighted whereas the amount of MS/BVPE (%, v/v) and the quantity (%) of micropores (diameter, d a suitable technique for the screening of samples with varying physicochemical properties and to quantitatively determine the parameters simultaneously within a few seconds.
Synthetic method of 1,2-bis(4-vinylphenyl)ethane
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Paragraph 0016-0027, (2019/12/02)
The invention relates to a synthetic method of an organic intermediate, in particular to a synthetic method of 1,2-bis(4-vinylphenyl)ethane. A phase transfer catalysis method is adopted, p-chloromethyl styrene, copper powder and iron powder are used as raw materials, water and methylbenzene are used as solvents, and a phase transfer catalyst is added to synthesize the 1,2-bis(4-vinylphenyl)ethane.According to the synthetic method, the risk in the production process is low, the yield is improved, side reactions are reduced, and a high-quality product is obtained.
Divinyl aromatic compounds and Di(methacrylates) prepared by acid-catalyzed transformations of bis[4-(1-hydroxyethyl)phenyl]alkanes
Zaitsev,Shvabskaya
, p. 1783 - 1794 (2012/02/15)
The mechanism of formation of divinyl aromatic monomers including p,p′-divinyldiphenylmethane and 1,2-p,p′-divinyldiphenylethane and of their dimerization via terminal vinyl groups was studied. The factors affecting the structure, composition, and propert
SYNTHESIS OF CYCLOBUTACYCLOPHANES CONTAINING GROUP 16 ELEMENTS BY INTRAMOLECULAR (2 ? + 2 ?) PHOTOCYCLOADDITION
Mizuno, Kazuhiko,Nakanishi, Kazuhisa,Otsuji, Yoshio
, p. 257 - 260 (2007/10/02)
The benzophenone-sensitized intramolecular (2 ? + 2 ?) photocycloaddition of bis(4-vinylphenylmethyl)sulfide and selenide in benzene afforded cyclobutacyclophanes containing sulfur and selenium in good yields.However, the photoreaction of bis(4-vinylpheny
Synthesis of ω-Unsaturated Acids
Mirviss, Stanley B.
, p. 1948 - 1951 (2007/10/02)
A short, high-yield method for the synthesis of ω-unsaturated acids have been developed that precludes any double-bond migration or hydrogenation.Key is the coupling reaction between Grignards of ω-unsaturated alkyl halides and the bromomagnesium salt of ω-bromo fatty acids.The reaction has been successfully extended to ω-bromo nitriles.The use of ω-chloro acids or α-bromo acids gives lower yields of heterocoupling products and substantial homocoupling.A catalyst study shows Li2CuCl4 to yield the most heterocoupling of several catalysts tried for the chloro acids, and Ni(II) or Cu(I) are best for the α-bromo acids.