The Preparation and Polymerization of p-Alkylstyrenes.<sup>1</sup> Effect of Structure on the Transition Temperatures of the Polymers
作者:C. G. Overberger、Charles Frazier、Jerome Mandelman、Harry F. Smith
DOI:10.1021/ja01110a010
日期:1953.7
Syndiospecific Synthesis of Longer <i>p-n-</i>Alkyl<i>-</i>Substituted Polystyrenes Using Monocyclopentadienyl-Type Titanium Catalysts
作者:Roderic P. Quirk、Myung-Ahn Ok
DOI:10.1021/ma035947a
日期:2004.6.1
Substituted styrenes with linear alkyl substituents (C-6 to C-12) at the Para position on the ring were synthesized and polymerized using the (Me)(5)CpTi(OMe)(3)/MAO catalytic system. Increased polymerization activities were observed for longer alkyl group (>C-6) substituted styrenes; all resulting polymers were highly syndiospecific (>99% rr) regardless of alkyl chain lengths. Syndiotactic poly(p-alkylstyrene)s were characterized by SEC, H-1 and C-13 NMR, DSC, and X-ray diffraction. No melting transition was observed for polymers prepared from p-methyl-, p-n-hexyl, and p-n-octylstyrenes. Side-chain-induced crystallization was observed for linear C-10 and C-12 alkyl-substituted polystyrenes (T-m approximate to 90 degreesC). The T-g decreased with an increase in the length of alkyl side chain up to C-8 length; above C-10 side-chain length, the T-g slightly increased. The T-g's of syndiotactic poly(p-n-alkylsyrene)s were significantly higher than those reported for the corresponding nontactic analogues.
NOVEL METHOD FOR PREPARING STYRENIC OLEFINS
申请人:LG Chem. Ltd.
公开号:EP1673319B1
公开(公告)日:2014-09-03
Novel method for preparing styrenic olefins
申请人:Lee Min-hyung
公开号:US20070032669A1
公开(公告)日:2007-02-08
The present invention relates to a method for preparing a styrenic olefin. The method of the present invention comprises the steps of: adding a catalyst and a solvent in a reactor and heating the reactor to create a reflux state; adding an alcohol starting material to the reactor dropwise at a constant rate; removing water generated by adding the alcohol starting material from the reactor, and purifying the obtained styrenic olefin. The method of the present invention is advantageous in minimizing byproducts and preparing styrenic olefins having a variety of substituents in high yield.