用于基于离子孔的离子选择电位计的性聚合物膜:Teflon AF是多么惰性的?
Chun-Ze Lai1, Secil S Koseoglu, Elizabeth C Lugert
1Department of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, USA.
Journal of the American Chemical Society
|January 13, 2009
概括
这项研究引入了性无形完聚合物作为离子选择性电极 (ISE) 膜的新型矩阵材料,提高了选择性和强度. 该研究详细介绍了这些新的pH测量电极的组成和性能.
科学领域:
- 电化学 电化学 电化学
- 材料科学 材料科学 材料科学
- 分析化学 分析化学
背景情况:
- 媒介提供独特的特性,如低极性,低极化相.
- 离子选择性电极 (ISE) 从坚固和选择性膜材料中受益.
- 像Teflon AF2400这样的多聚合物有可能成为ISE的新型矩阵材料.
研究的目的:
- 首次研究使用性无形 perfluoropolymer (Teflon AF2400) 作为离子选择性电极膜的矩阵.
- 为了评估ISEs的电位性能,选择性和稳定性,使用这种新的化膜组成.
- 了解聚合物矩阵对传感器选择性和膜电阻的影响.
主要方法:
- 使用Teflon AF2400作为聚合物矩阵,一个 perfluorooligoether塑化剂,一个特定的酸盐用于离子位点,以及一个新的H+离子体,制造ISE膜.
- 电位测量测量以评估Nernstian反应,在广泛的pH范围内的选择性和长期稳定性.
- 谱分析以确定聚合物矩阵中的功能组及其相互作用.
主要成果:
- ISEs表现出极好的电位选择性,Nernstian H+反应,以及增强的机械稳定性,保持了超过4周的选择性.
- 龙AF2400显著影响了传感器选择性,并在度超过15%时增加了膜电阻,归因于COOH功能组.
- 这些COOH组对各种离子 (Na+,K+,Ca2+) 和无质子离子体表现出结合亲和力,影响传感器性能.
结论:
- 含的无形完聚合物是强壮和选择性的ISE膜的有效基质材料.
- 在Teflon AF2400中存在COOH功能组,影响ISE性能,但它们的作用可以通过更高的离子体度来减轻.
- 在Teflon AF2400中对COF组的化学修饰提供了一条进一步定制ISE属性的途径,并引入新的功能.
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