共查询到20条相似文献,搜索用时 468 毫秒
1.
2.
3.
4.
5.
6.
7.
8.
Xiaomei Fang Ronald Hutcheon Daniel A. Scola 《Journal of polymer science. Part A, Polymer chemistry》2000,38(8):1379-1390
Microwave irradiation was applied to synthesize poly(ε‐caprolactam‐co‐ε‐caprolactone) directly from the anionic catalyzed ring opening of two cyclic monomers, ε‐caprolactam and ε‐caprolactone using a variable frequency microwave furnace, programmed to a set temperature and controlled by a pulsed power on–off system. Dielectric properties of ε‐caprolactam, ε‐caprolactone, and their mixture were measured in the microwave range from 0.4 to 3 GHz, showing that both ε‐caprolactam and ε‐caprolactone exhibited effective absorption of microwave energy to induce a fast chemical reaction. The microwave induced anionic copolymerization of ε‐caprolactam and ε‐caprolactone generated copoly(amide‐ester)s in yields as high as 70%. Conventional thermal and microwave copolymerization studies were also conducted for comparison with the microwave results. These studies demonstrated that an effective and efficient microwave method to copolymerize ε‐caprolactam with ε‐caprolactone in higher yield, higher amide content, and higher Tg 's, relative to the thermal process, has been developed. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1379–1390, 2000 相似文献
9.
10.
11.
12.
Brette M. Chapin Lauren D. Hughs James A. Golen Arnold L. Rheingold Adam R. Johnson 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(7):m191-m193
The title complex, [Ti(C5H5)(C2H6N)2Cl], exhibits two nearly planar dimethylamide groups oriented approximately perpendicular to each other. The Ti→cyclopentadienyl centroid vector lies nearly in the plane of one of the dimethylamide groups. Long‐range contacts between Ti—Cl and cyclopentadienyl H—C groups give rise to geometric ordering in the extended solid. 相似文献
13.
5-(α-Fluorovinyl)tryptamines 4a, 4b and 5-(α-fluorovinyl)-3-(N-methyl-1′,2′,5′,6′-tetrahydropyridin-3′- and -4′-yl) indoles 5a, 5b were synthesized using 5-(α-fluorovinyl)indole ( 7 ). The target compounds are bioisosteres of 5-carboxyamido substituted tryptamines and their tetrahydropyridyl analogs. 相似文献
14.
Reijo Sillanp Jordi Llop Clara Vias Francecs Teixidor Raikko Kiveks 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(8):900-901
In the title compound, (η5‐2,5‐dimethylpyrrolyl)[(7,8,9,10,11‐η)‐7‐methyl‐7,8‐dicarba‐nido‐undecaborato]cobalt(III), [3‐Co{η5‐[2,5‐(CH3)2‐NC4H2]}‐1‐CH3‐1,2‐C2B9H10] or [Co(C3H13B9)(C6H8N)], the CoIII atom is sandwiched between the pentagonal faces of the pyrrolyl and dicarbollide ligands, resulting in a neutral molecule. The C—C distance in the dicarbollide cage is 1.649 (3) Å. 相似文献
15.
Karel Mach Jií Kubita Ivana Císaov Petr tpni
ka 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(2):m116-m118
Reacting stoichiometric amounts of 1‐(diphenylphosphino)ferrocenecarboxylic acid and [Ti(η5‐C5HMe4)2(η2‐Me3SiC[triple‐bond]CSiMe3)] produced the title carboxylatotitanocene complex, [{μ‐1κ2O,O′:2(η5)‐C5H4CO2}{2(η5)‐C5H4P(C6H5)2}{1(η5)‐C5H(CH3)4}2FeIITiIII] or [FeTi(C9H13)2(C6H4O2)(C17H14P)]. The angle subtended by the Ti/O/O′ plane, where O and O′ are the donor atoms of the κ2‐carboxylate group, and the plane of the carboxyl‐substituted ferrocene cyclopentadienyl is 24.93 (6)°. 相似文献
16.
17.
18.
19.