Melamine and derivs

Melamine and Derivatives. See in Vol 8, M55-R to M56-L and the following Addnl Ref E.M. Smolin L. Rapoport, S-Triazines and Derivatives , Interscience, NY (1959), 374—75 [ ... Melamine has been suggested (C. Mannelli L. Bemardini, USP 1409963 (1922) CA, not found) as one component of a stable, easily handled explosive mixture, the other components of which are ammonium perchlorate or ammonium nitrate and carbon. When melamine is added to nitrocellulose or mixtures of nitroglycerin and nitrocellulose, the product is said (Anon, GerP 201215 (1908) CA, not found)... 

These are often melamine and derivatives or polyphosphate compounds such as APP. The mode of action of melamine appears to involve endothermic sublimation, acting as a heat sink, vapour-phase dissociation and also self-condensation under suitable conditions. APP achieves its flame retardant effect by intumescence and char formation acting as a barrier to combustion reactions. 

ATH) and magnesium hydroxide (MOH) as well as materials such as melamine and derivatives, ammonium polyphosphates (APPs), antimony oxide, and boron-containing materials such as zinc borate and others. 

A second logical approach to controlling pore size in self-assembled arrays, apart from steric crowding of pores through molecular functionalization (see above) is through the use of molecules of different dimensions. What may be viewed as the parent compound to the PTCDI-melamine array is the array formed between cyanuric acid and melamine (Figure 10a). The interaction formed between cyanuric acid and melamine, and derivatives of the two compounds, represents one of the most extensively studied structural motifs in supramolecular chemistry." ... 

Different behavior was found for SBS-MEL microcomposite, which had a TTI similar to that of pure SBS (85 s), but after 100-110 s a decrease in the HRR was observed, resulting in a delay in the PHRR (TTP = 239 than 204 s). Moreover, SBSMEL shows a PHRR similar to that for pure SBS. The mechanism of the fire retardant action of melamine derivatives is under investigation by many academic and industrial research groups however, it is well known that when exposed to heat and flames, melamine and derivatives decompose, absorbing heat and causing a cooling effect [46,47]. 

Combined condensation of melamine and of the acid residue is also shown by the phosphate and borate. In these cases however, the polymeric dehydrated compound derived from the acid is thermally stable up to above 500 C allowing chemical reactions with melamine condensation products simultaneously formed. The resulting material is stable to 950 C (phosphate, ca 30% of original salt) or to above 1100 C (borate, ca. 20% of original salt). 

Uses. IIic most important commercial use for benzonitiile is the synthesis of benzoguanamine, which is a derivative of melamine and is used in protective coatings and molding resins. See also Amino Resins and Cyanamides. 

Uses. The most important commercial use for benzonitrile is the synthesis of benzoguanamine, which is a derivative of melamine and is used in protective coatings and molding resins (see Amino RESINS Cyanamides). Other uses for benzonitrile are as an additive in nickel-plating baths, for separating naphthalene and alkylnaphthalenes from nonaromatics by azeotropic distillation (qv), as a jet-fuel additive, in cotton bleaching baths, as a drying additive for acrylic fibers, and in the removal of titanium tetrachloride and vanadium oxychloride from silicon tetrachloride. 

The complex between melamine and cyanuric acid (1 1) was reported in the literature in the late 1970s, but it was only in the early 1990s that the contributions from Whitesides and the concept of self-assembly popularized these systems [45]. Whitesides and co-workers reported the formation of tapes (Fig. 11.11), crinkled tapes and cyclic hexamers (rosettes) formed between barbituric acid and N,N -bis(p-substituted phenyl)melamine [46], In this they effectively blocked one face of melamine and, by manipulating substituents at the para position, different structures were obtained. Whiteside s putative suggestion that melamine/cyanuric acid formed an extended array (Fig. 11.12) was confirmed recently by Rao et al. with the crystal structure [47]. Hamilton and coworkers reported the crystal structure of a 5-substituted isophthalic acid derivative, which forms a cyclic aggregate held together with six pairs of hydrogen bonds, which in a way resembles the trimesic acid (Fig. 11.13) [48]. 

Flame retardants—Whereas halogen-containing Mannich bases arc mainly used as modifiers of macromolccular materials, as mentioned before, phosphorus derivatives arc employed as additives. These products arc obtained from phosphorous acid or phosphites 584 " and from other analogous phosphorus-containing compounds. N-Heterocyclcs, after reaction with melamine and formaldehyde (585), are also used as (lame retardants. -... 

It is finally worth mentioning that guanidine, melamine, and similar derivatives are frequently used as amine reagents or, sometimes, as preformed reagents.- " The above reactions are related to the analogous, even more commonly applied, amidomethylations (Chap. I, A.2) involving urea derivatives all these compounds have similar chemical features and applications. 

As far as the biocide properties are concerned, 0-Mannich bases containing extended hydrocarbon chains and used for their combined detcrgent/gcrmicidc action are worth mentioning. A good preserving function is also performed by plywood adhesives, based on urea, melamine, and formaldehyde, which are fixed by suitable iodo-derivatives presumably by amino- and amidomethylation reactions. 

N. Kimizuka, T. Kawasaki, K. Hirata, T. Kunitake, Supramolecular Membranes. Spontaneous Assembly of Aqueous BUayer Membrane via Formation of Hydrogen Bonded Pairs of Melamine and Cyanuric Acid Derivatives ,]. Am. Chem. Soc., 120,4094 (1998)... 

Whitesides et al. have prepared a series of large self-assembled structures containing multiple host-guest interactions. These assemblies were built around primary interactions between cyanuric acid (CA) and melamine (M) derivatives as illustrated by 18 (and were designated CA-M) where CA contains similar hydrogen... 

The results presented here demonstrate that a great variety of monomeric alkoxysilanes bearing 6-membered rings of melamine and cyclophosphazene is available. Thermal analysis of polysiloxanes derived from these precursor compounds exhibit remarkable stability. 

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