• Bulletin of the Korean Chemical Society
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• v.33 no.11
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• pp.3701-3705
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• 2012

A simple method has been developed for four-component synthesis of disubstituted 1,3,4-oxadiazoles using (N-isocyanimino)triphenylphosphorane, a primary amine, a carboxylic acid and biacetyl in $CH_2Cl_2$ by the Ugi-4CR/aza-Wittig sequence at room temperature in excellent yields.

• The International Journal of Costume Culture
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• v.6 no.2
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• pp.134-146
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• 2003

Polyester of linear homopolymer poly(ethylene terephthalate)(PET) was chemically modified through the formation of branched copolymer to improve the undesirable properties of fiber. Photo-induced graft copolymerization of the acrylic monomers acrylic acid (AA) and methyl acrylate (MA) in the liquid and vapor phase, respectively, onto N,N-dimetylformamide (DMF)-pretreated PET fibers was carried out. The effect of various synthesis conditions and DMF pretreatment of the PET on the graft yield was investigated. Grafting mechanism was analysed. The grafting was promoted by increasing DMF pretreatment temperature and amount of DMF retention in the fiber. The increasing biacetyl and monomer flow time, and irradiation time enhanced the grafting up to a certain amount and thereafter it decreased.