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91.
92.
Two oligomeric polyaryl ether-ketone-sulfones with acetylenic end groups have been prepared. These materials which are low melting and readily soluble in organic solvents on heating undergo reactions which are presumably trimerizations of the terminal acetylenic groups to give cured polymers which do not soften until about 200°C and which are stable in circulating air at 300°C with less than 10% weight loss in 10 days.  相似文献   
93.
94.
Several homopolymers and copolymers of the title compounds have been prepared by radical initiation with potassium persulfate or diethyl azobisisobutyrate. The copolymers exhibit a combination of the properties of the homopolymers of the monomers. The homopolymers are adhesive, very slightly elastic, and show cold flow. Several of the copolymers show possible promise for use as adhesives.  相似文献   
95.
New processable polyaromatic esters were prepared from 2,2′-diiododiphenyl-4,4′-dicarbonyl dichloride (I), isophthaloyl chloride (II), and/or terephthaloyl chloride (III) with 4,4′-isopropylidene diphenol (IV), 4,4′-sulfonyldiphenol (V), or resorcinol by interfacial condensation. In these polymers phenylacetylenyl groups were introduced by replacing the iodine. This process led to soluble and curable polymers. Polymer films can be prepared. After curing the polymers were insoluble and showed excellent thermal and chemical resistance. The curing process increased the polymers' softening temperature about 20°C.  相似文献   
96.
Polyaromatic ether–ketones and polyaromatic ether–keto–sulfones were sulfonated by suspending the polymer powders in dichloroethane containing liquid sulfur tiroxide and trialkyl phosphate at room temperature. It was found that more than one sulfonic group can be introduced per each repeating unit of the polymers without degradation. The sulfonated polymers were soluble in various organic solvents, and solubility and mechanical properties depended on the initial molecular weight of polymers as well as the degrees of sulfonation. Strong films can be cast from their dimethylformamide solutions.  相似文献   
97.
The monomer 4-bromo-4′-ethynyl biphenyl was synthesized and subsequently polymerized utilizing a bis (triphenylphosphine) palladium (II) chloride, copper (I) iodide, triphenylphosphine catalyst system in an organic amine solvent(s). The polymers produced were predominantly insoluble materials with reasonable thermal stability.  相似文献   
98.
Hollandite with Cr(III) in both tunnel and framework sites has been prepared hydrothermally from layered manganese oxide precursors.  相似文献   
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