Synthesis of Poly(Benzyl- eugenol) and Its Application as an Ionophore for a Potassium Ion-Selective Electrode

[摘要] Poly(benzyl eugenol)(PBE) as novel ionophores for a K+ ion selective electrode was  synthesized by acid catalyzed polymerization of benzyl eugenol. The polymerization product was characterized by IR and 1H NMR. The electrode membranes based on the polymer were prepared in the composition of 3 wt% of PBE, (67-n) wt% of 2-nitrophenyl octyl ether (o-NPOE) as a membrane plasticizer, n wt% of oleic acid as a lipophilic anionic additive (which n were varied from 0-10) and 30 wt% of PVC as a membrane matrix. Each membrane electrode was characterized for their performance as an ion-selective electrode membrane, that was selectivity, Nernst factor, limit of detection (l.o.d.), response time, and lifetime. Experimental results showed that the electrode membrane based on PBE with 3 wt% of oleic acid exhibited the best selectivity for K+ ion relative to other alkali and alkali earth metal ion. The K+-ISE based on PBE with the membrane composition of 3 wt% PBE, 3 wt% oleic acid, 64 wt% o-NPOE and 30 wt% PVC exhibited potentiometric selectivity toward NH4+, Na+, Mg2+, Ca2+, Ba2+ and Al3+ of  -0.6; -1.3; -3.2; -2.5, -2.2 and -2.5; respectively. This electrode gave a sub-Nernstian response with a slope of 56.3 mV/decade; the response time of c.a. 30 s; the dynamic range of 10-4 – 10-1 M and limit of detection of 10-4.7 M. The electrode may be used for continuous measurement at least up to two weeks. 

[学科分类] 分析化学

[关键词] : poly benzyl eugenol;ion-selective electrode;potassium ion;oleic acid