Phenolic triazine

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

Cyanate Esters of Poly Phenols and Phenolic Triazines (PT Resins)... 

Scheme 9. Synthesis of imido-phenolic-triazine net work polymers...

Scheme 10. Synthesis of maleimide-modified cyanate ester and imido-phenolic-triazine...

Cyanuric chloride has three chlorine substituents and a stable aromatic triazine ring. Different substituents can be introduced onto the triazine because the chlorines have different reactivities. Cyanuric chloride is used in pesticides, herbicides, dyes, detergent brighteners, and so on [48], Cyanuric chloride also is used in the manufacture of hindered-phenol triazines as antioxidants for polyolefin resins. Cyanuric chloride production is more than 100,000 ton/yr [49]. American Cyanamid, Nilok, and Geigy are three U.S. producers of cyanuric chloride [50]. 

Modified phenolics may be applied as matrix resins in composites. Cyanate esters of phenolics have the potential to replace conventional phenolics in thermo-structural applications. Thermal curing of the cyanate esters [149, 150] provide thermally stable phenolic-triazine networks, as shown at the bottom of Scheme 18. 

Currently available products are Aro-Cy from Ciba Speciality Chemicals, Primaset PT resins (phenolic triazines via cyanation of phenolic novalacs) from Allied Signal and a cyanate ester based on dicyclopentadiene phenol novalac marketed by Dow. The PT resins have superior thermal performance with thermo-oxidative stability comparable to BMI and PMR resins, coupled with excellent fire resistance. The triazine resin is soluble in ketones, esters, THF and chlorinated solvents. 

Cyanate ester and phenolic triazine (PT). The cyanate ester resins have shown superior dielectric properties and much lower moisture absorption than any other structural resin for composites. The physical properties of cyanate ester resins are compared to those of a representative... 

Nair and co-workers [203] reported polycyanate esters of an imide-modified novolac of different maleimide content. The resins underwent a two-stage independent thermal curing through trimerisation of the cyanate groups, as well as addition polymerisation of maleimide moieties. On heating, cyanate esters were transformed into an imido-phenolic-triazine network polymer. The cured resins exhibited a higher initial decomposition temperature compared with the cured maleimide novolacs. However, the thermal stability was found to be inferior to the conventional phenolic-triazine resin. 

Cyanate ester resins have shown superior dielectric properties and much lower moisture absorption than other structural resins for composites. Phenolic triazine... 

Many matrix choices are available, and each type has an impact on the processing techniques, physical and mechanical properties, and enviromnental resistance of the finished part. Thermoplastic and thermoset materials can be resin matrices. Thermoplastic matrices have been developed to increase hot/wet use temperature and the fracture toughness of composites. Thermosetting resins, however, are more common. The common thermoset matrices for composites include polyester and vinyl esters, epoxy, bismaleimide, polyimide, and cyanate ester and phenolic triazine resins. 

Table 10. Thermokinetic Properties of PMMA, PE, and Phenolic Triazine...

Das, S. et al. Phenolic-Triazine Resins Yield High-Performance Thermoset Composites. Modern Plastics, pp. 72-79, Feb. 1990. 

Cyanate ester and phenolic triazine (PT). The cyanate ester resins have shown superior dielectric properties and much lower moisture absorption than any other structural resin for composites. The physical properties of cyanate ester resins are compared to those of a representative BMI resin in Table 2.33. The PT resins also possess superior elevated-temperature properties, along with excellent properties at cryogenic temperatures. They are available in several viscosities, ranging from a viscous liquid to powder, which facilitates their use in applications that use liquid resins such as filament winding and transfer molding. 

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 ... 

Paracyclophane 93, 97, 101-102 Percolation theory 140-142 Phenol formaldehyd resins 72-75, 77, 78 Phenol maleimide resins 75 Phenolic triazine 87 Piezoelectricity 159-160 Poisson ratio 153, 179 Polyacrylates 19, 21, 22, 23 Polyamide, aromatic, linear 2, 30, 31, 127, 170-174, 184... 

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