92747-74-5Relevant academic research and scientific papers
Space environmentally durable polyimides and copolyimides
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, (2008/06/13)
Polyimides displaying low color in thin films, atomic oxygen resistance, vacuum ultraviolet radiation resistance, solubility in organic solvents in the imide form, high glass transistion (Tg) temperatures, and high thermal stability are provided. The poly(amide acid)s, copoly(amide acid)s, polyimides and copolyimides are prepared by the reaction of stoichiometric ratios of an aromatic dianhydride with diamines which contain phenylphosphine oxide groups in polar aprotic solvents. Controlled molecular weight oligomeric (amide acid)s and imides can be prepared by offsetting the stoichiometry according to the Carothers equation using excess diamine and endcapping with aromatic anhydrides The polyimide materials can be processed into various material forms such as thin films, fibers, foams, threads, adhesive film, coatings, dry powders, and fiber coated prepreg, and uses include thin film membranes on antennas, second-surface mirrors, thermal optical coatings, and multi-layer thermal insulation (MLI) blanket materials.
ORGANIC PHOSPHORUS COMPOUNDS 82. PREPARATION, PROPERTIES AND HERBICIDAL ACTIVITY OF 2-SUBSTITUTED 5-PHENOXY- AND 5-PYRIDYLOXY PHENYL PHOSPHONIC AND PHOSPHINIC ACID DERIVATIVES
Maier, L.,Duerr, D.,Rempfler, H.
, p. 19 - 36 (2007/10/02)
In the Cadogan reaction of 1,2-dinitro-4-chlorobenzene with phosphites and phosphonites the 2-nitro group is substituted but in 1,2-dinitro-4-alkoxycarbonylbenzenes the 1-nitro group is replaced exclusively.Extension of the Cadogan reaction to 4-phenoxy and 4-pyridyloxy substituted 1,2-dinitrobenzenes produced mainly 5-phenoxy and 5-pyridyloxy substituted 2-nitrophenylphosphonates and -phosphinates some of which show high herbicidal and plant growth regulating activity. 4- and 6-phenoxy or pyridyloxy substituted 2-nitrophenylphosphonates are herbicidally inactive.The herbicidal activity decreases from the phenoxy-phenylphosphonates to -phosphinates to pyridyloxy-phenylphosphonates when the same substitution pattern is present.The methyl esters 3a, 4a and 5a are the most active compounds in all three series.
