الفهرس 
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Abstract
Four series of nanosized polymers containing s-triazine moiety were prepared and characterized. Four different diacid chlorides namely 2-anilino-4,6-bis(phenoxy-4-carbonyl chloride)-s-triazine, 2-(N-1-naphthylamino)-4,6-bis(phenoxy-4-carbonyl chloride)-s-triazine,
2-anilino-4,6-bis(naphthoxy-2-carbonyl chloride)-s-triazine, 2-(N-1-naphthylamino)-4,6-bis (naphthoxy-2-carbonyl chloride)-s-triazine were prepared from their corresponding readily available diacids. Bulk production of the polymeric series were conducted by polycondensation of the appropriate diacid chloride with a number of commercially available diamines namely m-phenylene diamine, 2,6-diaminopyridine, benzidine, 4,4′-methylenedianiline, 4,4′-oxydianiline, 4,4′-sulfonedianiline, respectively, in DMAc at 0 °C. The polyamides were carefully characterized using infrared, ultraviolet, fluorescent emissions, elemental and thermal analyses. The polyamides were obtained in good yields and their inherent viscosities (ηinh) were in range 0.1-0.4 dL/g. The synthesis of nanosized aramides was conducted using nano-precipitation polymerization. The SEM analysis indicated that most of the polyamides were organized as well defined nanosized spheres, but in certain derivatives small amount of aggregated nanospheres were also observed. The formation of aggregate may be attributed to the molecular self-assembly via H-bond directed organization of molecular precursors.
Thermal analyses were studied up to 900 °C and results showed comparable thermal behavior based on the produced char yields. As expected, polymeric series derived from p-phenylenediamine moiety exhibited better thermal stability than their analogues containing m-phenylenediamine. While the naphthyl / phenyl interchange has no influence on thermal properties in some cases; the latter were dramatically improved upon this interchange in many other cases. Obviously, also the pyridine / phenylene interchange has no influence on the thermal properties of the addressed polymers and benzidine- and sulfone- containing polymers exhibited better thermal stabilities than their analogues containing ether or methylene flexible linkages. The LOI values indicated that twelve polymeric types are classified as slow burning while ten polymeric types are classified as self-extinguishing polymers.
The optical data of the prepared polymers demonstrated interesting structure-property correlations. The polymers exhibited emissions ranging from blue to orange wavelength depending on the nature of signaling unit. Additionally, while the introduction of a naphthyl moiety has no significant influence on the electronic properties in some cases, the naphthyl / phenyl interchange led to either red shifted absorptions or disrupt the conjugation and thus blue shifted absorptions in other analogues. Benzidine-containing polyamides exhibited the most red-shifted emission peaks compared to other analogues containing biphenyl systems and this could be attributed to the highly conjugated system.
In conclusion and to the best of our knowledge, we prepared for the first time a new series of well-defined nanosized spheres aramides- containing N- and O- aryl-s-triazine. Structure–properties were carefully studied and the results proved interesting correlations. Thermal analyses data up to 900 °C showed high thermal behavior and most polymers were classified either as slow burning or self-extinguishing polymers. The polymers exhibited.