Allophane, synthesis

Alkali metal (haloarylsulfonyl)thio-phenoxides, 364 Alkaline hydrolysis of nylon-6,6, 568-569 of PET, 549-550 Alkyd resins, 18, 30-31, 59-60 synthesis and cure of, 102 Alkylphenolic resins, 376 Alkylphenols, 376, 400 Allophanates, 227... 

Ethyl allophanate, preparation of, for synthesis of allophanyl hydrazide and urazole, 6 48,... 

It is foimd that in spectra of polymers synthesized the bonds are present, typical of allophanate structures (1,310 cm ) [6], This testifies about high probability of the reaction between urethane group and isocyanate at temperature increase to 120 - 140°C during synthesis of polyurethane isoeyanurate materials under selected conditions. 

A new method for the synthesis of linear, film- and fibre-forming polyurethanes free of allophanate branches and cross-links, by reacting activated diol bis(carbonate)s with diamines, has also been reported [255]. 

The structural analysis of the samples PP ADMH = 2 1 obtained at 60 and 80°C in the absence of catalysts shows the formation of a branched structure at temperatures lower than those required for the formation of allophanate (120-140°C) and biuret (100°C) structures [1]. The ability of the ADMH to form hydrazinium cations leads to the assumption that the elastomer synthesis with the participation of ADMH involves formation of reactive centers of ionic nature, similarly to the Ritter reaction, where the synthesis of the N-substituted amides of carboxylic acids passes through a stage of carbonium ion formation... 

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