Phosphorescent Oxygen Sensors Utilizing Sulfur−Nitrogen−Phosphorus Polymer Matrixes: Synthesis, Characterization, and Evaluation of Poly(thionylphosphazene)-b-Poly(tetrahydrofuran) Block Copolymers

Autor: Xiao-Hua Liu, Mitchell A. Winnik, Zhen Pang, Ian Manners, Peter Park, Ahmad Yekta, Yizeng Ni, Xin Lu, Christopher E. B. Evans, Xijia Gu, Andrew R. McWilliams, Raiph Ruffolo
Rok vydání: 2000
Předmět:
Zdroj: Analytical Chemistry. 72:1894-1904
ISSN: 1520-6882
0003-2700
Popis: We examine the use of thionylphosphazene-based block copolymers as matrixes for oxygen sensor applications. Poly(aminothionylphosphazene)-b-poly(tetrahydrofuran) (PATPy-PTHFx) block copolymers were prepared via reaction of ring-opened poly(chlorothionylphosphazene) with THF and subsequently with excess n-butylamine (to form PBATPy-PTHFx) or methylamine (to form PMATPy-PTHFx). The block copolymers were characterized by NMR, gel permeation chromatography, and differential scanning calorimetry. Films of PBATPy-PTHFx block copolymers containing platinum octaethylporphyrin or [Ru(dpp)3]Cl2 (dpp = 4,7-diphenyl-1,10-phenanthroline) as the oxygen-sensitive chromophore were prepared, and time-scan experiments were carried out to determine the diffusion coefficients, Do2, and solubilities, So2, of oxygen therein. Despite microphase separation, the data fit well to a simple Fick's law description of oxygen diffusion and gave Do2 values smaller than that for the n-butylamino-substituted PBATP635. For films freshly annealed above the melting point of PTHFx, the Do2 values were 35-50% (dye-dependent) larger than after aging 3 days at room temperature. Films with [Ru(dpp)3]Cl2 as the dye were evaluated as media for phosphorescent pressure-sensing. The dye-containing polymer films exhibit linear Stern-Volmer-like plots, even at high dye concentrations, as well as good photostability, and significantly higher sensitivity to oxygen quenching than simple mixtures of the analogous homopolymers.
Databáze: OpenAIRE
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