Hostname: page-component-745bb68f8f-l4dxg Total loading time: 0 Render date: 2025-01-15T06:42:52.274Z Has data issue: false hasContentIssue false
  • English
  • Français

Film Formation by Electrodeposition of Ionized Aramids

Published online by Cambridge University Press:  26 February 2011

Motowo Takayanagi  and
Keiko Koga
Motowo Takayanagi
Affiliation:
Faculty of Engineering, Kyushu Sangyo University, Matsukadai, Fukuoka 813, Japan
Keiko Koga
Affiliation:
Faculty of Engineering, Kyushu Sangyo University, Matsukadai, Fukuoka 813, Japan
Get access

Abstract

Poly(p-phenylene terephthalamide) (PPTA) recognized as rigid-rod polymer is converted into polyanion by the reagent of sodium methylsulfinylcarbanion in dimethylsulfoxide (DMSO), which is dissolved in DMSO to form a dark red colored homogeneous solution. The electrolysis of PPTA polyanion in DMSO, which has also rigid-rod shape due to resonance effect, gives a PPTA gel swollen by DMSO on the anode. The gel is easily converted to a PPTA film. The structural change during the process was followed by the Xray diffraction. The PPTA film neutralized with acidic water and dried has the hydrogen-bonded sheet in crystal standing perpendicular to the film surface, whereas the same film annealed at temperatures above 300°C has the hydrogen-bonded sheet parallel to the film surface. The latter form is the stable structure. The orientational transition was energetically discussed by taking into the activation energy of the crystalline relaxation. A uniform and homogeneous film was prepared by using a coaxial rotating electrode cell. The modulus was 11 GPa and the strength was 150 MPa. The addition of polyacrylonitrile to the electrolytic solution as the frictionproviding polymer which was removed from the gel after electrolysis, provided the mechanical anisotropy, especially after annealing at 350°C: the modulus along the orientation direction was 14 GPa and the strength was 370 MPa.

The PPTA film unannealed or annealed below 200°C in an unstable orientational tate was used as a matrix of electropolymerization of electroconductive polymers such as polypyrrole, polyaniline and polythiophene, resulting in the electroconductive composite film of PPTA with improved mechanical properties. The PPTA/polyyyrrole with p-toluenesulfonate as a dopant had the conductivity of 50 Scm−1, the modulus of 6.2 GPa and the strength of 140 MPa. The conductivity was stabilized as high as 150°C. The SEM observation and the analysis of dynamic viscoelasticity proved the composite film being composed of two-phase structure.

A novel aramid, poly(p-phenylene[2,5-bis(4-carboxyphenyl)pyrazine]amide) (PPPA), was synthesized. PPPA is soluble in pure sulfuric acid to form liquid crystal. The X-ray diffraction pattern of the oriented PPPA film predicts that the conformation of the PPPA chain in crystal takes all-trans form, giving the good agreement of the fiber period with the calculated one. It is noticeable that PPPA is dissolved into DMSO with formation of polyanion by the reagent of sodium methylsulfinylcarbanion and the electrolysis of the solution is conducted, resulting in a PPPA film on the anode like PPTA. The aramid copolymer of PPTA forming a molecular coil was unable to be electrodeposited. Thus, it is believed that only the rigid-rod polyelectrolytes are capable of film formation by electrolysis.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 134: Symposium J – Materials Science and Engineering of Rigid-Rod Polymers , 1988 , 283
Copyright
Copyright © Materials Research Society 1989

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Arpin, M. and Straziell, C., Compte Rend. Sci.(C) 280, 1293 (1975); Makromol. Chem. 177, 581 (1976); Polymer 18, 591 (1977).Google Scholar
2. Erman, E., Flory, P.J. and Hummel, J.P., Macromolecules 13, 484 (1980).Google Scholar
3. Tashiro, K., Kobayashi, M., and Tadokoro, H., Macromolecules 10, 413 (1977)CrossRefGoogle Scholar
4. Weyland, H.G., Polym. Bull. 3, 331 (1980).Google Scholar
5. Flood, J.E., White, J.L., and Fellers, J.F., J. Appl. Polym. Sci. 27, 2965 (1982).CrossRefGoogle Scholar
6. Takayanagi, M. and Katayose, T., J. Polym. Sci.:Polym. Chem. Ed. 19, 1133 (1981).Google Scholar
7. Koga, K., Ueta, S., and Takayanagi, M., Polym. J. 20, 639 (1988).CrossRefGoogle Scholar
8. Koga, K., Shuto, K., Ueta, S., and Takayanagi, M., Rep. Progr. Polym. Phys. Japan 31, 365 (1988).Google Scholar
9. Northolt, M., Eur. Polym. J. 10, 799 (1974).Google Scholar
10. Hasegawa, R., Chatani, Y., and Tadokoro, H., Preprints of Soc. Crystallography, Japan 1973, p. 21.Google Scholar
11. Haraguchi, K., Kajiyama, T., and Takayanagi, M., J. Appl. Polym. Sci. 23, 915 (1979).CrossRefGoogle Scholar
12. Xu, D.-F., Okuyama, K., Kumamaru, F., and Takayanagi, M., Polym. J. 16, 31 (1984).CrossRefGoogle Scholar
13. Haraguchi, K., Kajiyama, T., and Takayanagi, M., Sen-i Gakkaishi 23, T–535 (1977).Google Scholar
14. Koga, K., lino, T., Ueta, S., and Takayanagi, M., Rep. Progr. Polym. Phys. Japan 31, 445 (1988); submitted to Polym. J.Google Scholar
15. Buckley, L.J., Royland, D.K., and Wnek, G.E., J. Polym. Sci.: Polym. Phys. Ed. 25, 2179 (1987).Google Scholar
16. Ueta, S., Fukuda, Y., Koga, K., and Takayanagi, M., Reports of Faculty of Engineering, Kyushu Sangyo Univ., 1988, in press.Google Scholar