Copolymers Obtained by Grafting Reaction of 2-Methyl-2-Oxazoline Onto Poly(4-Methylphenoxyphosphazene) and their Micelle Formation

Abstract

Poly(dichlorophosphazene) of a low molecular weight was prepared by the thermal polymerization of hexachlorocyclotriphosphazene in the presence of aluminum chloride (10 wt %). The chloro groups were replaced by 4-methylphenoxy groups to give [NP(OC₆H₄-p-CH₃)]_n. The methyl groups of the polymer were brominated with N-bromosuccinimide and benzoyl peroxide, resulting in [NP(OC₆H₄-p-CH₃)_x(OC₆H₄-p-CH₂Br)_y]_n. The brominated unit content was 5% – 20%. These polymers were employed in initiating polymerization of 2-methyl-2-oxazoline. The weight average molecular weight of the 5% grafted polymer measured by GPC in chloroform was 11,000. Their micelle formation in water was investigated by fluorescence spectroscopy and surface tension measurement.

Keywords::

• polyphosphazene
• graft copolymer
• micelle