scholarly journals Multigap superconductivity in the Mo5PB2 boron–phosphorus compound

2020 ◽  
Vol 22 (9) ◽  
pp. 093016
Author(s):  
T Shang ◽  
W Xie ◽  
D J Gawryluk ◽  
R Khasanov ◽  
J Z Zhao ◽  
...  
Keyword(s):  
2020 ◽  
Vol 15 ◽  
pp. 155892502090132
Author(s):  
Sang-Hoon Lee ◽  
Seung-Won Oh ◽  
Young-Hee Lee ◽  
Il-Jin Kim ◽  
Dong-Jin Lee ◽  
...  

To prepare flame-retardant epoxy resin, phosphorus compound containing di-hydroxyl group (10-(2,5-dihydroxyphenyl)-9,10-dihydro-9-oxa-10-phospha phenanthrene-10-oxide, DOPO-HQ) was reacted with uncured epoxy resin (diglycidyl ether of bisphenol A, YD-128) and then cured using a curing agent (dicyandiamide, DICY). This study focused on the effect of phosphorus compound/phosphorus content on physical properties and flame retardancy of cured epoxy resin. The thermal decomposition temperature of the cured epoxy resins (samples: P0, P1.5, P2.0, and P2.5, the number represents the wt% of phosphorus) increased with increasing the content of phosphorus compound/phosphorus (0/0, 19.8/1.5, 27.8/2.0, and 36.8/2.5 wt%) based on epoxy resin. The impact strength of the cured epoxy resin increased significantly with increasing phosphorus compound content. As the phosphorus compound/phosphorus content increased from 0/0 to 36.8/2.5 wt%, the glass transition temperature (the peak temperature of loss modulus curve) increased from 135.2°C to 142.0°C. In addition, as the content of phosphorous compound increased, the storage modulus remained almost constant up to higher temperature. The limiting oxygen index value of cured epoxy resin increased from 21.1% to 30.0% with increasing phosphorus compound/phosphorus content from 0/0 to 36.8/2.5 wt%. The UL 94 V test result showed that no rating for phosphorus compounds less than 19.8 wt% and V-1 for 27.8 wt%. However, when the phosphorus compound was 36.8 wt%, the V-0 level indicating complete flame retardancy was obtained. In conclusion, the incorporation of phosphorus compounds into the epoxy chain resulted in improved properties such as impact strength and heat resistance, as well as a significant increase in flame retardancy.


2003 ◽  
Vol 59 (11) ◽  
pp. m484-m486 ◽  
Author(s):  
Philip A. W. Dean ◽  
Donald C. Craig ◽  
Marcia L. Scudder ◽  
Ian G. Dance

The reported crystal structures of Ph4P+·I− and Ph4As+·I− have been re-examined. An apparent instance of substitutional dimorphism could not be reproduced and, contrary to an earlier report, tetraphenylarsonium iodide, [As(C6H5)4]I or Ph4As+·I−, was found to be isostructural with the phosphorus compound. The cation and anion are both located on \overline 4 symmetry sites. The crystal packing involves linear chains of cations in fourfold phenyl embraces.


ChemInform ◽  
2005 ◽  
Vol 36 (19) ◽  
Author(s):  
Zhi Gen Yu ◽  
Hao Gong ◽  
Ping Wu
Keyword(s):  

2015 ◽  
Vol 47 ◽  
pp. 290
Author(s):  
Hideyuki Takahashi ◽  
Takuya Osawa ◽  
Yasuhiro Suzuki ◽  
Kazushige Goto ◽  
Nobukazu Kasai ◽  
...  
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