| The chemical modification of several polyphosphazene surfaces was investigated. Phosphazene hydrogels were grafted onto organic polymer surfaces. Polyphosphazene surfaces were sulfonated and oxidized. Fluoroalkoxy polyphosphazene surfaces were modified by nucleophiles. The spreading behavior of some phosphazenes at the air/water interface was examined as a prelude to monolayer formation. Biological tests were conducted to determine toxicity, mutagenicity, and blood and cell compatibility. The surfaces were extensively characterized and had enhanced wettability and biocompatibility.; The water-soluble polyphosphazene, {dollar}rm lbrack NP(OCHsb2CHsb2OCHsb2CHsb2OCHsb3)sb2rbrack sb n{dollar}, was cross-linked when exposed to gamma rays to form hydrophilic, water-swellable membranes and hydrogels. The polymer was grafted onto the surfaces of organic polymer films by coating the surfaces and then treating them with {dollar}sp{lcub}60{rcub}{dollar}Co gamma rays.; Phosphazene compounds were sulfonated. Phosphazenes containing aromatic side groups were sulfonated for various reaction times and temperatures to yield a series of water-soluble polyelectrolytes and hydrophilic films.; The surfaces of poly (di-(4-methylphenoxy)phosphazene), ({dollar}rm NP(OCsb6Hsb4CHsb3)sb2rbrack sb n{dollar}, were chemically oxidized to yield surfaces with carboxylic acid groups. The extent of surface oxidation could be controlled by varying the reaction time and temperature.; Films of poly (bis(trifluoroethoxy)phosphazene), ({dollar}rm NP(OCHsb2CFsb3)rbrack sb n{dollar}, underwent surface modification when treated with either hydroxide or alkoxide anions. Aqueous sodium hydroxide, in the presence of a phase transfer agent, converted a highly hydrophobic surface to one with hydrophilic and adhesive character. The principal chemical reaction was found to be a replacement of trifluoroethoxy side groups at the polymer surface by either {dollar}rm -Osp-NBusb4sp+{dollar} or alkoxide units.; The spreading behavior of phosphazene compounds on an aqueous subphase was examined by obtaining the pressure vs. area isotherm with a Langmuir-Blodgett trough equipped with an electrobalance and a Wilhemy plate. Several of the compounds exhibited monolayer behavior.; The phosphazene compounds tested were neither toxic nor mutagenic, although several amphiphilic polymers did exhibit antibiotic activity. Preliminary screening by the Lindholm Test indicated that the sulfonated, oxidized, and hydrogel grafted surfaces had enhanced blood compatibility. The sulfonated surfaces also appear to be excellent substrates for cell adhesion and growth. |
