نتایج جستجو برای: ethylene1 hexene copolymerization

تعداد نتایج: 3269  

Journal: :Journal of the American Chemical Society 2006
Claudio De Rosa Finizia Auriemma Paolo Corradini Oreste Tarallo Stefania Dello Iacono Eleonora Ciaccia Luigi Resconi

Propene-hexene copolymers crystallize in a new polymorphic form of isotactic polypropylene when the concentration of hexene is higher than nearly 10-15 mol %. The hexene units are included in the crystals, inducing an increase of density that allows crystallization of 3-fold helical chains in a trigonal unit cell according to the space group R3c or Rc, where the helical symmetry of the chains i...

2010
Joseph Zakzeski Hae Ryun Lee Yi Ling Leung Alexis T. Bell

The one-pot synthesis of butanol and heptanol from propene and 1-hexene, respectively, was performed using Ru3(PPh3)Cl2 and Rh(CO)2(acac) in the presence of triphenylphosphene. The effects of various reaction parameters, including catalyst concentration, gas partial pressures, and temperature, were investigated. Two methods for performing the one-pot synthesis were developed and are discussed. ...

Journal: :Chemical communications 2015
Shyeni Paul Yunqing Zhu Charles Romain Rachel Brooks Prabhjot K Saini Charlotte K Williams

Controlled routes to prepare polyesters and polycarbonates are of interest due to the widespread application of these materials and the opportunities provided to prepare new copolymers. Furthermore, ring-opening copolymerization may enable new poly(ester-carbonate) materials to be prepared which are inaccessible using alternative polymerizations. This review highlights recent advances in the ri...

2016
Zhongyuan Wu Manfred T. Reetz Klaus Harms

In the title compound, C16H14O, the cyclo-hexene ring has a half-chair conformation. The mean plane, calculated through all non-H atoms of the mol-ecule, except for the central CH2 atoms of the cyclo-hexene ring, which deviate by 0.340 (3) and -0.369 (3) Å from this mean plane, has an r.m.s. deviation of 0.012 Å. In the crystal, there are C-H⋯π contacts present, resulting in the formation of zi...

2012
Shaaban K. Mohamed Mehmet Akkurt Antar A. Abdelhamid Phillip E. Fanwick Herman Potgeiter

In the xanthene ring system of the title compound, C(23)H(25)BrO(4), the 4H-pyran ring is almost planar [maximum deviation = 0.040 (3) Å] and the cyclo-hexene ring adopts a sofa conformation. The cyclo-hexene ring attached to the xanthene system is puckered [Q(T) = 0.427 (3) Å, θ = 55.0 (4) ° and ϕ = 164.4 (6) °]. In the crystal, mol-ecules are linked to each other by O-H⋯O and C-H⋯O hydrogen b...

2006
Shiro KOBAYASHI

Enzymatic ring-opening copolymerization of lactones was carried out by using Pseudomonas f luorescens lipase in bulk. In the copolymerizaton of r-caprolactone (E-CL) and b-valerolactone at 60°C for 10 days a copolymer with molecular weight of 3.7 x 103 was obtained and its structure was found to be of random structure having both units from 13C NMR anlaysis. Effects of the feed ratio, the react...

2016
Martin S. Engler Kerstin Scheubert Ulrich S. Schubert Sebastian Böcker

For many years, copolymerization has been studied using mathematical and statistical models. Here, we present new Markov chain models for copolymerization kinetics: the Bernoulli and Geometric models. They model copolymer synthesis as a random process and are based on a basic reaction scheme. In contrast to previous Markov chain approaches to copolymerization, both models take variable chain le...

2009
Yan Wang Jin-Long Wu

In the title compound, C(28)H(27)NO(2), the oxazinone ring adopts a twist-boat conformation and the cyclo-hexene ring has a twisted envelope conformation. The crystal structure is stabilized by weak non-classical inter-molecular C-H⋯O hydrogen bonds.

2008
S. Murugavel P. S. Kannan A. SubbiahPandi T. Surendiran S. Balasubramanian

In the title compound, C(12)H(13)N, two methyl-ene C atoms of the cyclo-hexene ring are disordered over two sites with occupancies of 0.591 (10) and 0.409 (10); both disorder components adopt half-chair conformations. The crystal structure is stabilized by inter-molecular N-H⋯π and C-H⋯π inter-actions.

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید