Ion-selective electrodes
First Claim
1. In a flow-through electrode assembly having as an element a tube for the passage of liquid sample through said assembly and a membrane comprising a membrane matrix of an organic plastic material containing a non-volatile solvent plasticizer and an ion-active material dissolved in said solvent plasticizer, the improvement to provide a structurally stable membrane of increased active area and a flow-through electrode assembly of increased operating life in which said tube comprises a porous tube in which the pores are impregnated with said membrane matrix, said porous tube comprising a material which is essentially nonreactive with a solution to be tested and in which pores are generally uniformly distributed throughout said tube, said pores communicating between the inside of said tube and the exterior of said tube and having a maximum diameter of about 100 microns, said plasticizer being essentially nonreactive with and a nonsolvent for said tube material.
5 Assignments
0 Petitions
Accused Products
Abstract
An electrode assembly of the flow-through type comprising as a key element a porous and a preferably microporous tubular material impregnated with a matrix of an organic plastic material containing a nonvolatile solvent plasticizer and an ion-active material dissolved in the plasticizer, the plasticizer not being a solvent for the tubular material. There is also disclosed an electrode assembly involving a membrane material in which the membrane material communicates electrically directly through a metal conductor.
5 Citations
21 Claims
- 1. In a flow-through electrode assembly having as an element a tube for the passage of liquid sample through said assembly and a membrane comprising a membrane matrix of an organic plastic material containing a non-volatile solvent plasticizer and an ion-active material dissolved in said solvent plasticizer, the improvement to provide a structurally stable membrane of increased active area and a flow-through electrode assembly of increased operating life in which said tube comprises a porous tube in which the pores are impregnated with said membrane matrix, said porous tube comprising a material which is essentially nonreactive with a solution to be tested and in which pores are generally uniformly distributed throughout said tube, said pores communicating between the inside of said tube and the exterior of said tube and having a maximum diameter of about 100 microns, said plasticizer being essentially nonreactive with and a nonsolvent for said tube material.
- 4. A flow-through electrode assembly comprising a tube having a generally cylindrical tube wall defining therewith a cylindrical liquid sample flow path through said electrode, characterized in that said tube comprises a porous material having pores generally uniformly distributed therethrough communicating between said inner flow path and the exterior of said tube, said pores impregnated with a membrane matrix material comprising an organic plastic material containing a solution of a nonvolatile plasticizer and an ion-active material, said plasticizer being a solvent for said ion-active material, but not for the material of said tube wall, further characterized in that the maximum pore size of the pores in said tube material is 100 microns, and further characterized by a direct electrode connection through a metallic conductor between the membrane material in said pores and the exterior of said flow-through electrode assembly.
Specification