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Indexed by:期刊论文

Date of Publication:2012-09-01

Journal:POLYMER DEGRADATION AND STABILITY

Included Journals:SCIE、EI、Scopus

Volume:97

Issue:9

Page Number:1807-1814

ISSN No.:0141-3910

Key Words:Polyamides; 1,3,5-Triazine; Synthesis; High performance polymers

Abstract:The syntheses and properties of phenyl-1,3,5-triazine functional aromatic polyamides are described. From 2,4,6-trichloro-1,3,5-triazine (1), an aromatic diacid, namely 4-(4,6-diphenyl-1,3,5-triazin-2-yl) benzoic acid (6), was prepared by a three-step reaction in satisfactory yields. A model reaction of 6 with aniline (7) was carried out to determine feasibility of amidization. Aromatic poly(phenyl-1,3,5-triazine amide)s (10a-10e) with inherent viscosities ranging from 0.28 to 1.26 dL/g were synthesized from Yamazaki phosphorylation polycondensation of 6 with aromatic diamines (9a-9e). The reactions were conducted in N-methyl-2-pyrrolidone (NMP) to yield high-molecular-weight amorphous polymers in essentially high yields. All polymers are readily soluble in NMP and N,N-dimethylacetamide (DMAc) at room temperature, and formed transparent films from their solution. The films exhibit good mechanical properties with tensile strengths of 71.5-94.7 MPa, elongations at break of 6.1-10.0%, and initial moduli of 2.3-2.8 GPa except that of 10a is slightly brittle. These polymers have high glass transitions from 311 to 330 degrees C, depending on the aromatic diamines used in the polycondensation, and they demonstrate excellent thermal stabilities in excess of 440 degrees C (5% weight loss in air). Isothermal TGA measurements reveal that the obtained benzene-1,3-diamine-based poly(phenyl-1,3,5-triazine amide) (10b) belongs to the most superior class of heat resistant polymers such as polyamide Kevlar (R). (C) 2012 Elsevier Ltd. All rights reserved.