Trimethyl cyanurate

Trimethyl isocyanurate [827-16-7] can be synthesized in 60% yield by the reaction of CA with dimethyl sulfate in alkaline medium (13) or with diazomethane (63) and in essentially quantitative yield by thermal rearrangement of trimethyl cyanurate [877-89-4]. Isomerization of alkyl cyanurates to the corresponding isocyanurates is frequendy observed (11,64). 

The alkyl cyanurates are thermally stable, although they decompose on passing over red hot platinum metal to yield cyanic acid and alkenes. (Trimethyl cyanurate is exceptional it decomposes to methyl isocyanate.)... 

Table 2 The trimethyl-cyanurates and -thiocyanurates and their C chemical shifts.

The thiocyanurates are readily hydrolyzed in acid to cyanuric acid and a thiol. Trimethyl trithiocyanurate reacts with sodium sulfide to give the trisodium salts. Melamine is formed on treatment of the thiocyanurates with aqueous ammonia at high temperatures the alkylthio groups are replaced sequentially <59HC(l3)l,p.lll), and can be removed using Raney nickel (equation 25) . 

The formation of keto-phosphonate structure within macromolecule leads to the removal of internal unsaturation. Triallyl cyanurate and ionizing irradiations [210] made a E-P block copolymer-PE blend thermally stable. Triallyl cyanurate increases the crosslinking density probably due to addition reactions between polymeric and allyl radicals produced by ionizing radiation. The addition of 2,2,4-trimethyl-l,2-di-hydroquinoline and bis[4(l-methyl-1-phenylethyl)pheny 1]-amine stabilized a PE-EPDM blend against heat [211]. Popov et al. [212] studied the ozone effect on PE-iPP blend. The oxidation rate was detected in relation to... 

Reactive admixture for free radical induced cro linking include pcdyfunctimial monomers for an increase in the crosslinking eflidency of polyalkenes, trimethyl propane trimethacrylate, pentaerythritol tetraallyl ether, pentaerythritol trtramdh-acrylate, triallyl cyanurate [24,25] etc. are used. An optimum concentraticn of polyfunctional monomer depends on various fat ors and for a certain cro inkable system can only be found empirically. 

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