Polish version

Login form

register


Print

E. Witek, A. Kochanowski, E. Bortel

A new method of the synthesis of hydrofobically modified poly(acrylic acid)

Polimery 2004, No 1, 3


Summary

A new method of the synthesis of hydrofobically modified poly(acrylic acid) (HMPAA) (Scheme A) is based on a dissolution of initial poly(acrylic acid) (PAA) in thionyl chloride, which at temp. 60°C reacts with COOH groups so the chloroyl groups COCl create. Chloroyl groups were subjected to partial amidation with dodecylamine and then the unreacted COCl groups were hydrolized to the carboxyl groups. HMPAA obtained this way contained 2.55% of nitrogen and in aqueous solutions (0.1 M NaCl) showed, in viscometric measurements, the behavior being characteristic for amphiphylic polymers. It means the dependence ηsp/c = f(c) significantly deviates from a straight line in contrast to the initial PAA. Further confirmation of an amphiphylic character of HMPAA is the decrease in surface tension of water from 72.7 mN/m (just water) to 42 mN/m (1% solution of HMPAA), at temp. 25°C. 13C NMR spectra of PAA and HMPAA were interpreted. In HMPAA spectrum there are additional signals coming from carbon atom of CONH group and from C atoms of aliphatic chain from dodecylamine. An explanation of the differences of the courses of curves of potentiometric titration of PAA and HMPAA is also given.


Keywords: amphiphylic polymers, hydrophobically modified poly(acrylic acid), synthesis, amphiphylicity characteristics


E. Witek, A. Kochanowski, E. Bortel

A new method of the synthesis of hydrofobically modified poly(acrylic acid)