| 摘要 |
Aqueous dispersions of polyphosphazene polymers are prepared by dissolving the polymer in a volatile organic solvent, then combining with water under agitation and heat to evaporate solvent leaving the aqueous dispersion for use in coatings and impregnations. Nonionic or anionic dispersing agents improve stability, preferably phosphate esters of polyoxyethylene for fire-retardancy. Halogen-free polyphosphazene copolymers having a phenoxy group and either a phenyl phenoxy or naphthoxy group or both are provided as aqueous dispersions for coatings on metal or glass with superior adhesion and freedom from halogen fumes when subject to burning. Preferred copolymers have molecular weight of 100, 000 or more, ratio of phenoxy groups to the other groups of 30:70 to 95:5 and up to 10% of the groups being such as methoxy phenoxy, vinyl phenoxy or allyl phenoxy, and are mostly amorphous with Tg of at least O` C. |
