Triazine polymers

Keywords. Cyanate ester, Polycyanurates, Phenolic-triazine, Polymer matrix composite, Cure kinetics, Polymer blends, Cyanate-epoxy blend, Bismaleimide-triazine resins, Aerospace structure... 

Scheme 4. Synthesis of cyanato phosphazene and crosslinked phosphazene-triazine polymer...

A significant research effort has been directed toward fluorinated triazine polymers,208,218-221 and examples of the formation of these interesting elastomers of very high thermal stability are given (Eqs. 67218 and 68219). 

Ren S, Dawson R, Layboum A et al (2012) Eunctional conjugated microporous polymers from 1,3,5-benzene to 1,3,5-triazine. Polym Chem 3 928-934... 

Longer pendant groups which encompass diphenylether moieties have been incorporated into the quinoxaline and as-triazine polymer systems. No increase in solubility was described however, a substantial decrease in glass transition temperatures was obtained from the diphenylether pendant when compared to the phenyl pendant polymer systems. 

These three monomers, and oligomeric pre-polymers made from them, are being produced and marketed by several companies. Among them one finds Hi-Tek Polymers [538], Rhone-Poulenc [539], Mobay [458] and Mitsubishi [458]. Triazine polymers with shorter average distance between the trifunctional branchpoints are the phenolic triazine (PT) resins currently in the process of commercialization by Allied-Signal Inc. [540, 541], Their generic structure is ... 

Melamine - formaldehyde polymers. Melamine (2 4 6-triamino-1 3 5-triazine), obtained by heating dicyandiamide under pressure, condenses with formalin to give melamine - formaldehyde polymers (Beetle - Melamine), which have similar uses, but better stability to heat... 

A series of compounded flame retardants, based on finely divided insoluble ammonium polyphosphate together with char-forming nitrogenous resins, has been developed for thermoplastics (52—58). These compounds are particularly useful as iatumescent flame-retardant additives for polyolefins, ethylene—vinyl acetate, and urethane elastomers (qv). The char-forming resin can be, for example, an ethyleneurea—formaldehyde condensation polymer, a hydroxyethylisocyanurate, or a piperazine—triazine resin. 

A large number of hindered phenoHc antioxidants are based on the Michael addition of 2,6-di-/ f2 -butylphenol and methyl acrylate under basic catalysis to yield the hydrocinnamate which is a basic building block used in the production of octadecyl 3-(3,5-di-/ f2 butyl-4-hydroxyphenyl)propionate, [2082-79-3], tetrakis(methylene-3(3,5-di-/ f2 butyl-4-hydroxylphenyl)propionate)methane [6683-19-8], and many others (63,64). These hindered phenolic antioxidants are the most widely used primary stabilizers in the world and are used in polyolefins, synthetic and natural mbber, styrenics, vinyl polymers, and engineering resins. 2,6-Di-/ f2 -butylphenol is converted to a methylene isocyanate which is trimerized to a triazine derivative... 

Oligomeric hindered amine light stabilizers are effective thermal antioxidants for polypropylene. Thus 0.1% of A[,Af-bis(2,2,6,6-tetramethyl-4-piperadinyl)-l,6-hexanediamine polymer, with 2,4,6-trichloro-l,3,5-triazine and 2,4,4-trimethyl-2-pentaneainine [70624-18-9] (35) (Fig. 5), protects polypropylene multifilaments against oxidation when exposed at 120°C in a forced-air oven (22) for 47 days. 3,5-Di-/ l -butyl-4-hydroxytoluene [128-37-0] (0.1%) affords protection for only 14 days. 

Instead of using thermal energy to trigger the hydrogen abstraction mechanism, photo-induced reactions can be also be used to successfully crosslink acrylic PSAs [74-76], In this case, photoactive compounds, such as for example those containing benzophenone, anthraquinone or triazine nuclei are compounded with the polymer or copolymerized as one of the monomers. After drying, the adhesive... 

UV absorbers have been found to be quite effective for stabilization of polymers and are very much in demand. They function by the absorption and harmless dissipation of the sunlight or UV-rich artificial radiation, which would have otherwise initiated degradation of a polymer material. Meyer and Geurhart reported, for the first time in 1945 [10], the use of UV absorber in a polymer. They found that the outdoor life of cellulose acetate film was greatly prolonged by adding phenyl salicylate (salol) [10]. After that, resorcinol monobenzoate, a much more effective absorber, was introduced in 1951 [11] for stabilization of PP, but salol continued to be the only important commercial stabilizer for several years. The 2,4-dihydroxybenzophenone was marketed in 1953, followed shortly by 2-hydroxy-4-methoxybenzophenone and other derivatives. Of the more commonly known UV absorbers, the 2-hydroxybenzophenones, 2-hy-droxy-phenyl-triazines, derivatives of phenol salicylates, its metal chelates, and hindered amine light stabilizers (HALS) are widely used in the polymer industry. 

The efficacy of RF in stabilizing small rings is well illustrated by the fact that the azete from trifluoro-l,2,3-triazine is considerably more reactive. Trapping experiments were unsuccessful and a polymer was isolated at room temperature. The dimer (41) forms an observable anion with CsF, which confirmed the endo structure [87CC1699 90JCS(P1)975, 90JCS(P1)983], In contrast, trifluoro-l,2,4,-triazine is resistant to vapor phase photoysis and flow pyrolysis [87JCS(P1) 1251]. 

The synthesis of comb-like polymers with regular branching (in contrast to random branching) has been performed in the following way 91) A linear polystyrene precursor fitted with carbanionic sites at both ends is reacted first with 1,1-diphenylethylene (to decrease the nucleophilicity of the sites) and then with a calculated amount of triallyloxytriazine to get chain extension. Each triazine residue still carries one allyloxy... 

The most widely employed techniques for the extraction of water samples for triazine compounds include liquid-liquid extraction (LLE), solid-phase extraction (SPE), and liquid-solid extraction (LSE). Although most reports involving SPE are off-line procedures, there is increasing interest and subsequently increasing numbers of reports regarding on-line SPE, the goal of which is to improve overall productivity and safety. To a lesser extent, solid-phase microextraction (SPME), supercritical fluid extraction (SEE), semi-permeable membrane device (SPMD), and molecularly imprinted polymer (MIP) techniques have been reported. 

---