A method is described, that allows a quick and simple testing of the burning behaviour of plastics. It takes into account ignition time as well as afterflame time;properties that are characteristic for the burning beh...A method is described, that allows a quick and simple testing of the burning behaviour of plastics. It takes into account ignition time as well as afterflame time;properties that are characteristic for the burning behaviour of a particular plastic material. The procedure is easy to perform, it does neither require injection-moulded samples nor expensive equipment. The method provides a classification of the burning behaviour. It is especially suitable for a screening of plastic materials complementing established methods like UL-94, GWFI and LOI, and may find application in the development of flame retardants.展开更多
Catalytic amounts of cesium carbonate are sufficient to initiate the “silyl method”-type step-growth polymerization of phenylene-bis-TMS-ethers and -thioethers with activated aryl fluoride monomers, and can thus be ...Catalytic amounts of cesium carbonate are sufficient to initiate the “silyl method”-type step-growth polymerization of phenylene-bis-TMS-ethers and -thioethers with activated aryl fluoride monomers, and can thus be used instead of ce-sium fluoride or potassium carbonate. Cesium fluoride is very hygroscopic and potassium carbonate is generally used in equimolar amounts. The efficiency of catalytic amounts of cesium carbonate is demonstrated by the synthesis of poly(phenylene ether ether ketone) and poly(phenylene sulfide sulfone) examples.展开更多
文摘A method is described, that allows a quick and simple testing of the burning behaviour of plastics. It takes into account ignition time as well as afterflame time;properties that are characteristic for the burning behaviour of a particular plastic material. The procedure is easy to perform, it does neither require injection-moulded samples nor expensive equipment. The method provides a classification of the burning behaviour. It is especially suitable for a screening of plastic materials complementing established methods like UL-94, GWFI and LOI, and may find application in the development of flame retardants.
文摘Catalytic amounts of cesium carbonate are sufficient to initiate the “silyl method”-type step-growth polymerization of phenylene-bis-TMS-ethers and -thioethers with activated aryl fluoride monomers, and can thus be used instead of ce-sium fluoride or potassium carbonate. Cesium fluoride is very hygroscopic and potassium carbonate is generally used in equimolar amounts. The efficiency of catalytic amounts of cesium carbonate is demonstrated by the synthesis of poly(phenylene ether ether ketone) and poly(phenylene sulfide sulfone) examples.
