Preparation and properties of copolyamides-6,6F and copolyamides-4,8F containing oligo(tetrafluoroethylene)segments
✍ Scribed by Norbert Steinhauser; Rolf Mülhaupt
- Publisher
- John Wiley and Sons
- Year
- 1994
- Tongue
- English
- Weight
- 586 KB
- Volume
- 195
- Category
- Article
- ISSN
- 1022-1352
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
Two families of copolyamides‐6,6F and copolyamides‐4,8F containing various amounts of bis‐ and tris(tetrafluoroethylene) segments were prepared to study the influence of such fluorine‐containing segments on bulk and surface properties. In a solution polycondensation process telechelic aliphatic diamines, obtained by reacting dimethyl α,ω‐dicarboxylatooligo(tetrafluoroethylene)s with excess diamines, e. g., tetramethylenediamine and hexamethylenediamine, were polymerized with activated bis(4‐nitrophenyl) adipate and bis(4‐nitrophenyl) suberate. In the presence of various stoichiometric amounts of the aliphatic diamines, the fluorine content varied between 0 and 39 wt.‐% and the inherent viscosities between 0,27 and 1,02 dL/g. As content and segment length of the oligo(tetrafluoroethylene) segments increased, the polymer solubilities in organic solvents and the contact angles to water increased, whereas melting temperatures, crystallinities (as measured by means of differential scanning calorimetry and wide‐angle X‐ray scattering (WAXS)) and thermal stabilities (as determined by means of thermogravimetric analysis of the weight loss encountered at elevated temperatures) were reduced markedly. The WAXS measurements reflected changes of crystal structures with increasing fluorine content.
📜 SIMILAR VOLUMES
A new aminocarboxylic acid bearing an enamino nitrile segment was used as starting material for the preparation of modified homopolyamide and various copolyamides. The polycondensations were carried out by the phosphorylation method. Poly(benzamide) was also prepared under the same experimental cond
N,W-Bis(2-chloroethyI)-1,1,52-tetrafluoroethane-l,2-dicarboxamide (3a) was prepared by refluxing 15,80 g (57,2 mmol) 2 a in 120 mL thionyl chloride for 16 h. After distilling off the thionyl chloride, the white residue was recrystallized in methanol and dried at 120°C. Yield: 16,12 g (90%); m.p. 164
Copolyamides based on poly( m-phenylene isophthalamide) and poly-(p-phenylene terephthalamide), to which 1,6-diaminohexane units were regularly inserted every 3 or 5 phenylene monomer units, were synthesized. The copolymers were obtained by condensation of individually prepared diamino-and dicarboxy