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Polyamides X.34: A New Class of Polyamides with Long Alkane Segments
Author(s) -
Ehrenstein Moritz,
Smith Paul,
Weder Christoph
Publication year - 2003
Publication title -
macromolecular chemistry and physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.57
H-Index - 112
eISSN - 1521-3935
pISSN - 1022-1352
DOI - 10.1002/macp.200350026
Subject(s) - polyamide , diamine , polymer chemistry , differential scanning calorimetry , materials science , thermogravimetric analysis , amide , polymer , condensation polymer , chemistry , organic chemistry , composite material , physics , thermodynamics
A new series of semi‐crystalline polyamides (PA), which comprise extended aliphatic segments between the amide moieties and which display an interesting amphiphilic character has been synthesized and characterized. The polymers PA‐2.34 , PA‐4.34 , PA‐8.34 , PA‐10.34 , and PA‐12.34 were prepared by melt‐polycondensation of salts of tetratriacontanedioic acid and the respective short‐chain diamine. The thermal properties of these polymers were investigated by differential scanning calorimetry, thermogravimetric analysis, and dynamic mechanical thermal analysis. The new polyamides exhibit melting temperatures that depend on the length of the diamine and range between 166 ( PA‐12.34 ) and 190 °C ( PA‐2.34 ). Solid transitions were observed between 38 and 57 °C. The materials displayed a rather limited solubility in common polyamide solvents, but readily dissolved in alkylsulfonic acids. All members of the series formed thermo‐reversible gels in the highly polar sulfuric acid and 1,2,3,4‐tetrahydronaphthalene, reflecting their interesting amphiphilic character. Young's moduli and tensile strengths of melt‐processed, isotropic films of the polyamides investigated were in the range of 0.5–0.7 GPa and 20.30 MPa, respectively, independent of the length of the diamine used.Melting temperatures of polyamides PA‐X.34 (x) and 1,2,3,4‐tetrahydronaphthalene/PA‐X.34 gels (37.5 wt.‐% polyamide, determined from the second DSC heating scans) (+).