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The composite films of polydimethylsiloxane (PDMS) and cyanoethylsucrose (CR‐U) were prepared and investigated as an electroactive silicone actuator in the air. CR‐U is highly viscose and soluble in tetrahydrofuran (THF) and acetone (ACT). The composites showed a phase‐separation structure, in which the spherical CR‐U dispersed in the PDMS domain. The films from THF had an asymmetric cross‐sectional view, in which CR‐U large sphere dispersed with a thin skin layer of PDMS on one side. On the other hand, the films from ACT had a symmetric cross‐sectional structure, in which CR‐U small sphere dispersed uniformly without a PDMS thin skin layer. By applying DC electric field, the films from THF deformed by expanding the thin skin layer regardless of the electric field polarity. The films from ACT showed almost no deformation. The space‐charge distribution explained deformation behavior.

Asymmetric 1,3-dipolar cycloaddition reactions between N-methylindoles and several cyclic carbonyl ylides that were derived from diazodiketone or diazoketoester precursors in the presence of both achiral Rh and chiral lanthanoid metal catalysts are described. For the six-membered cyclic carbonyl ylides derived from 1-diazo-5-aryl-2,5-pentanedione precursors, the cycloaddition reactions were carried out using Rh2(OAc)4 (2 mol %) and the chiral Pybox-Ph2-Lu(OTf)3 complex (10 mol %) as catalysts, resulting in high enantioselectivities (83% to >98% ee (exo)) along with relatively good exo-selectivities (exo:endo = 65:35 to 94:6) and yields (63-85%). For the five-membered cyclic carbonyl ylide derived from 1-diazo-2,4-pentandione precursor, the cycloaddition reaction with 5-bromo-1-methylindole was carried out in the presence of Rh2(OAc)4 (2 mol %) and the chiral Pybox-Ph2-Er(OTf)3 complex (30 mol %) as catalysts, resulting in relatively good enantioselectivity (78% ee) and endo-selectivity (endo:exo = 81:19).

Asymmetric 1,3-dipolar cycloaddition reactions between N-methylindoles and several cyclic carbonyl ylides that were derived from diazodiketone or diazoketoester precursors in the presence of both achiral Rh and chiral lanthanoid metal catalysts are described. For the six-membered cyclic carbonyl ylides derived from 1-diazo-5-aryl-2,5-pentanedione precursors, the cycloaddition reactions were carried out using Rh2(OAc)4 (2 mol %) and the chiral Pybox-Ph2-Lu(OTf)3 complex (10 mol %) as catalysts, resulting in high enantioselectivities (83% to >98% ee (exo)) along with relatively good exo-selectivities (exo:endo = 65:35 to 94:6) and yields (63-85%). For the five-membered cyclic carbonyl ylide derived from 1-diazo-2,4-pentandione precursor, the cycloaddition reaction with 5-bromo-1-methylindole was carried out in the presence of Rh2(OAc)4 (2 mol %) and the chiral Pybox-Ph2-Er(OTf)3 complex (30 mol %) as catalysts, resulting in relatively good enantioselectivity (78% ee) and endo-selectivity (endo:exo = 81:19).

液相と平衡にある気相のトリハロメタンの濃度は温度の上昇とともに増大する。さらに, 河川水を原水とした水道水中のトリハロメタンの主成分であるCHCl3は90℃においては液相よりも気相での濃度が高くなった。湯沸かし器で加熱水中に空気を吹き込み, 気相と液相の接触面積を増加させると, トリハロメタンは液相から気相に速く移動した。トリハロメタンを効果的に除去するためには, トリハロメタンを含む気体を装置外へ排出することが必要である。使用初期の活性炭は, 加熱水中でトリハロメタンを吸着した。細孔径が広く分布している活性炭は, 吸着したトリハロメタンを完全には脱離できないが, 細孔径が1.4nm程度の分布の狭い活性炭は, 100℃程度でも吸着したトリハロメタンをほぼ100%脱離することができた。したがって, トリハロメタンの除去のために, 分布の狭い活性炭は長い寿命をもっていた。2-メチルイソボルネオールは加熱水中でも活性炭に吸着され, 100pg/l程度の濃度であれば, 活性炭はその吸着性能を長期間維持した。

Water transport under an osmotic pressure difference across a cation-exchange membrane was measured in 0.005molkg-1 HCl+MCl(mc)/membrane/MCl(mc) system, where M in MCl represents alkali metal and mc is the molality of the electrolyte solutions ranging from 0 to 0.1molkg-1. Hydrocarbonsulfonic acid-type cation-exchange membrane Aciplex K-101 was used. The volume flux observed in the system at mc≠0 was always larger than that in the system at mc=0, although the apparent molality differences across the membrane of the systems were same. Bell-shaped dependence of the osmotic volume flux was observed on mc. In general, the order of the magnitude of the volume flux was LiCl>NaCl>KCl. Electroosmotic volume flux across the membrane was also measured at 0.01molkg-1 to estimate the reduced transport number of water τ0. The values of τ0F represent the amount of transported water followed by the flow of one mole of the monovalent cations. The values of τ0F were 1.7, 26.4, 18.0, and 12.8 for H+, Li+, Na+, and K+, respectively. The anomalous osmotic properties observed in the mixed aqueous solutions of HCl and alkali metallic halide would be due to the displacement of water caused by the counter transport of proton and alkali metallic ion across the membrane in addition to the normal osmotic volume flux.

To establish a method for removing residual chlorine and trihalomethanes from hot water effectively, an activated carbon column was placed in an electric pot. The variation in concentrations of those compounds was measured by altering the setting position of the activated carbon column and the flow rate of the test solution in the column.Activated carbon was found to act as a catalyst of the decomposition of residual chlorine. Removal capability based on decomposition decreased with increase in space velocity, and increased with temperature rise. Although activated carbon serves as adsorbent for the removal of trihalomethanes, the amount of trihalomethanes absorbed in activated carbon was quite small in hot water.The efficiency of residual chlorine removal was low when the activated carbon column was placed at the bottom of the pot. To realize a greater efficiency of the removal, a higher flow rate of test solution through the activated carbon column was required. When the column was placed at the outlet of solution circulation pipe, considerable part of residual chlorine was removed. As a consequence of removing residual chlorine the generation of trihalomethanes was prevented. The concentration of trihalomethanes in solution decreased when the solution was kept hot. The lifespan of activated carbon is very long since it acts as catalyst but not as adsorbent.

水道水中の残留塩素, トリハロメタン, かび臭などの成分を除去する方法を確立するために, 加熱, 沸騰, 保温の仕方による, pH値と残留塩素, トリハロメタン, かび臭の濃度変化を測定した。水道水を沸騰近くまで加熱するとpH値はアルカリ性となった。この条件下では, 残留塩素は不揮発性の次亜塩素酸イオン (ClO-) の状態で存在している。したがって, 水道水中の残留塩素は, 揮発よりも水道水中に溶解している前駆有機物との反応により減少すると推測される。水道水を沸騰まで加熱すると, トリハロメタンは, 残留塩素と前駆有機物との反応により増加するとともに, 揮発により減少する。トリハロメタンを除去する上で, 沸騰時に発生する泡の状態が重要な役割を果たしている。したがって, トリハロメタンを除去するために, もっとも効果的な泡の発生方法を検討することは重要と考えられた。残留塩素が溶液中に存在するときは, 水道水中のトリハロメタンを除去した後でも, トリハロメタンは増加した。沸騰は2-メチルイソボルネオールを除去するのにも有効であった。2-メチルイソボルネオールの量は沸騰エネルギーの増加とともに減少した。

A large amount of work of membrane phenomena has been published in the past. However, the most of them were due to a concentration gradient, a pressure gradient and an electric potential gradient, and membrane phenomena due to a temperature gradient were a little compared with the others. This is because heat flux is considerably high compared with mass fluxes and reliable measurements of the nonisothermal membrane phenomena were very difficult. In this review experimental method and typical data of thermal membrane potential are presented, and the analysis of them based on nonequilibrium thermodynamics is included.

A theory for bi-ionic potential, especially for bi-co-ionic potential, which is a potential difference across a membrane due to the difference in co-ions, is proposed. A high water content interpolymer membrane of poly(ethyleneimine) and poly(vinyl alcohol) was prepared as a low-charged anion-exchange membrane. The potential difference Δψ for the system of KCl/membrane/1/2MgCl2 or 1/2CaCl2 was measured by changing the external electrolyte concentrations cs and analyzed according to the theory. The bi-co-ionic potential Δψ increased with increasing cs at low concentrations, and after the potential Δψ reached a maximum value, the potential Δψ decreased with increasing cs at high concentrations; that is, a bell-shaped dependence of Δψ was observed against cs. This is because the low mobility of co-ions with charge number +2 in the charged membranes increases with increasing cs and finally reaches the mobility in the free electrolyte solutions.

The thermal membrane potentials were measured across poly(styrene)-based copolymer anion-exchange membranes with 4.5 and 8% divinylbenzene having anion-exchange groups with different hydrophobicity for various electrolyte solutions. Linear relationships between the membrane potential (Δ ψ ) and the temperature difference (Δ T ) or the logarithmic temperature difference (Δ ln T ) were observed when the average temperature T av was kept at 308.2 K and Δ T varied from −10 to +10 K. The values of Δ ψ /Δ T against log a ± decreased with increasing hydrophobicity of the ion-exchange groups. The mean transported entropy of the counterions s − in the membrane was estimated by combining data for the thermal membrane potential, thermo-osmosis, and electro-osmosis. For hydrophilic IO − 3 -form membranes having relatively high water content, the water term (Δ ψ /Δ T ) 0 is predominant in Δ ψ /Δ T . The equation derived from a set of entropy and coupled absolute temperature difference was a good approximation in the range of small temperature differences.

The thermal membrane potential across anion-exchange membranes having various hydrophobic anion-exchange groups was measured for various electrolyte solutions. A good linear relationship between the thermal membrane potential (Δψ) and the logarithmic temperature difference (Δln T) was observed. The temperature coefficient of the thermal membrane potential (Δψ/Δln T) was found to be a function of the logarithmic activities of ions with a slope of RTc/F for 1-1 electrolytes and RTc/(2F) for 1-2 electrolytes, where Tc is the constant temperature of the solution on one side of the membrane. The absolute value of Δψ/Δln T decreased with increasing the molality of the external electrolyte solutions. The absolute value of Δψ/Δln T in KCl solutions was higher than that in KIO3 solutions. For halide ions the order of the absolute values of the thermal membrane potential (Δψ) was Cl− > Br− > I−, which corresponds to the order of the values of the B-coefficient in the Jones–Dole expression for the viscosity of the s...

Solvent transport across poly(styrene)-based anion-exchange membranes with various ion-exchange groups was measured under a temperature gradient to discuss the effect of hydrophobicity of the membranes on thermoosmosis. Two varieties of poly(styrene)-based copolymer membranes with 10 and 14% divinylbenzene as cross-linking agent were prepared as base membranes. Benzyltrimethylammonium, benzyltriethylammonium, benzyltripropylammonium, benzyltributylammonium, and benzyltripentylammonium were introduced in the base membranes as anion-exchange groups. The thermoosmotic volume flux toward the hot solution side decreased with increasing the length of alkyl groups (increasing hydrophobicity of the groups), and at last, for the membranes with benzyltripentylammonium, the direction of thermoosmosis reversed: from the hot to the cold solution side as is observed for usual hydrophobic membranes. The transported energy and the mean transported entropy of water in the membranes estimated from the data of thermoosmosis...

A bilayered ion-exchange membrane consisting of poly(styrene-co-4-vinylpyridinium ion) (anion-exchange membrane) and a gel-like mixture of poly(vinyl alcohol) and poly(acrylic acid) (cation-exchange membrane) was prepared. The bilayered membrane strip, one end of which is fixed, is placed between two carbon electrodes in a cell which contains KCl solution of 0.01 mol kg−1 molality. If the electric field is applied from the cation-exchange layer side to the anion-exchange layer side, the cation-exchange layer becomes the K− form and is elongated. On the contrary, if the electric field is reversed, dissociation of water into H+ and OH− occurs at the interface between the two layers. Consequently, the carboxyl group becomes the acid form, resulting in contraction of the layer. The anion-exchange layer, which contains a strong base group, becomes either the Cl form or the OH form with changing the electric field, but there is no detectable change in volume. Thus, if the electric field applied to the membrane is periodically reversed, periodical bending of the bilayered membrane is observed.

Theoretical equations for the thermoosmosis and thermal membrane potential across a charged membrane were derived using a set comprising the energy flux and the coupled logarithmic temperature-difference force as a dissipation function of irreversible processes. In order to obtain phenomenological equations in discontinuous systems by integrating phenomenological equations in continuous systems, it was assumed that temperature and total chemical potential are continuous at the interface between the membrane and the external solution. The new equations were compared with approximate equations derived previously from a set comprising the entropy flux and the coupled temperature-difference force as the dissipation function. Moreover, an equation for the thermal membrane potential was also derived using an alternative method by summing two parts: the equilibrium potential differences between the membrane and the external solutions on both sides of the membrane (two Donnan potentials) and the thermal-diffusion...

Poly(4-vinylpyridine/styrene) and poly(N-vinyl-2-methylimidazole/styrene) type membranes (SA-14 and SA-15) were prepared as weak-base anion-exchange membranes, and strong-base anion-exchange membranes (SA-14(4) and SA-15(4)) were prepared by quaternizing them with CH3I. Solvent transport across the membranes was measured in electrolyte solutions under a temperature difference. Thermoosmosis toward the cold solution side was clearly observed for membranes SA-14 and SA-15 in KCl and HCl solutions. However, the direction of thermoosmosis was toward the hot side in H2SO4 solutions because the membrane is considerably ionized with H2SO4 and the water in the membrane is more stabilized than that in the external solutions. Thermoosmosis across the quaternized membranes SA-14(4) and SA-15(4) occurred toward the hot side in KCl and KIO3 solutions. The difference between the mean transported entropy of water in the membrane, ⁼s0, and the partial molar entropy of the external solution, s0, was estimated from the the...

The dependence of the electric potential difference on time under a pressure gradient across hydrogel membranes, obtained by esterification of poly(vinyl alcohol) and poly(acrylic acid), was measured. At the moment when a pressure difference was applied, a sharp spike of the electric potential difference was observed. The overall variation of the electric potential difference on time consisted of two different processes. One of them, which gradually increased with time, and finally reached a steady-state value, reflects a relaxation of polymer chains dissolved in the liquid phase of the gel membrane under the pressure difference. The other, which showed a sharp inverse spike just after applying the pressure difference, and reached zero immediately, may have been caused by a transformation of the membrane matrix due to a sudden change in pressure before the migration of the water, that is, by compaction of the membrane matrix. When hydrogen molecules of the carboxyl groups in the gel membrane were exchange...

Solvent transport across hydrocarbonsulfonic acid-type cation-exchange membranes was measured for aqueous electrolyte solutions under a temperature difference and an osmotic pressure difference. The hydrocarbonsulfonic acid-type cation-exchange membranes, Aciplex® K-181, Aciplex® K-182, and Neosepta® C66-5T with the H+, Li+, Na+, K+, NH4+, CH3NH3+, (CH3)2NH2+, (CH3)3NH+, (CH3)4N+, (C2H5)4N+, (n-C3H7)4N+, and (n-C4H9)4N+ forms were used. The direction of thermoosmosis across the membranes with the H+ and the Na+ forms was from the cold side to the hot side, as observed for various anion-exchange membranes. However, the direction was from the hot side to the cold side for the membranes with the ammonium and the alkylated ammonium ion forms, except for Neosepta® C66-5T with the (CH3)4N+, (C2H5)4N+, and (n-C3H7)4N+ forms. This is why the entropy of the water in the membranes will increase with increasing the number of hydrogens combining with the nitrogen of the alkylated ammonium counterions, because they ar...

Solvent transport across a hydrophobic PTFE membrane and the modified PTFE membranes was measured in water under a temperature difference. Moreover, thermoosmosis across the anion-exchange membrane, Neosepta AM-1, was measured for poly (acrylamide) and urea solutions. The direction of thermoosmosis across the PTFE and the modified PTFE membranes was from the hot side to the cold side, whereas that across anion-exchange membrane was from the cold side to the hot side. Thermoosmosis across the modified PTFE membranes decreased with increasing the hydrophilic groups in the membrane. For poly (acrylamide) and urea solutions the absolute values of volume fluxes decreased with increasing the concentration of the external solution, because of the decrease of the entropy difference of water between the membrane and the external solution.

The dependence of the streaming potential across hydrogel membranes on time was measured. The gel membranes used were obtained by blending various amounts of poly(vinyl alcohol) and poly(sodium L-glutamate), which have different average molecular weights per cross-linked unit. The streaming potential increased rapidly just after applying a pressure difference and then increased gradually up to a steady-state value. The time dependence of the streaming potential was analyzed as the relaxation of the polymer chains dissolved in the liquid phase of the membrane. The relaxation for all the gel membranes consisted of a single component. The relaxation time was long if the gel had a large average molecular weight per cross-linked unit. The effects of cross-linking and the concentration of the external solution on the relaxation time are discussed.

Thermal membrane potentials across the perfluorosulfonic acid-type membrane, Flemion S, were measured for HCl, alkali metal chlorides, and ammonium and methyl ammonium chlorides. The difference between the mean molar transported entropy of the counterions in the membrane and the partial molar entropy of the counterions in the external solution\(\left( \begin{gathered} = \hfill \\ s_ + ---s_ + \hfill \\ \end{gathered} \right)\) was determined from the experimental data on thermal membrane potential, thermoosmosis and electroosmosis. The sign of the thermal membrane potential in HCl solution varies from positive to negative with the concentration. In HCl and alkali metal chloride solutions, the order of their thermal membrane potentials (−Δψ/ΔT) is H+>Li+=Na+>K+ which is roughly the inverse of that of the crystallographic radii of the ions. However, the order of their entropy differences\(\left( \begin{gathered} = \hfill \\ s_ + ---s_ + \hfill \\ \end{gathered} \right)\) is H+>Na+>K+>Li+ which is just the inverse of that of their thermoosmotic coefficients (D) or the entropy difference of water\(\left( \begin{gathered} = \hfill \\ s_0 ---s_0 \hfill \\ \end{gathered} \right)\) in thermoosmosis. For the ammonium and methyl ammonium ion forms, the orders of both −Δψ/ΔT and\(\left( \begin{gathered} = \hfill \\ s_ + ---s_ + \hfill \\ \end{gathered} \right)\) increase with an increasing number of methyl groups: (CH3)4N+>(CH3)3NH+>(CH3)2NH2+> CH3NH3+>NH4+, which is also the inverse of that ofD or\(\left( \begin{gathered} = \hfill \\ s_0 ---s_0 \hfill \\ \end{gathered} \right)\).

The thermal membrane potential cell with solution inlet channels was constructed from two blocks of poly(methyl methacrylate). Using the cell the thermal membrane potentials across anion-exchange membranes Aciplex A-201, A-211, and A-221, and Neosepta AM-1 were observed in inorganic electrolytes: KF, KCl, KI, KNO3, KClO3, and KIO3, and in organic electrolytes: HCOONa, CH3COONa, CH3COOK, and C6H5COONa. The thermal membrane potential Δψ across the anion-exchange membrane was always positive at the cold solution side. The temperature coefficient of the thermal membrane potential per unit temperature difference Δψ/ΔT is proportional to the logarithmic activities of the ions and the slope of this plot was R/F in the range of ideal permselectivity for the counterions except Aciplex A-221. The transported entropies of the counterions in the membrane were estimated by combining data for the thermal membrane potential, thermoosmosis, and electroosmosis. For all types of membranes, both terms of water and ions in t...

Solvent transports across the perfluorosulfonic acid-type membrane Flemion S were measured for aqueous electrolyte solutions under a temperature difference and under an osmotic pressure difference. H+, Li+, Na+, K+, NH 4 + , CH3NH 3 + , (CH3)2NH 2 + , (CH3)3NH+, (CH3)4N+, (C2H5)4N+, (n-C3H7)4N+ and (n-C4H9)4N+ were used as counterions. Water flux across the membrane in HCl solution is higher than that in the other electrolyte solutions because hydrogen ions can exchange with the hydrogen of the neighbor water molecules and contribute to the water transport across the membrane as a proton jump in conductivity. The direction of thermoosmosis across the membrane in HCl, NaCl, (CH3)4NCl and (C2H5)4NCl solutions was from the cold side to the hot side and that in LiCl, KCl, NH4Cl, CH3NH3Cl, (CH3)2NH2Cl and (n-C4H9)4NBr solutions was from the hot side to the cold side, although thermoosmosis across anion-exchange membranes always occurs toward the hot side.

Solvent transport across anion-exchange membranes was measured for aqueous KF, KCl, KNO 3 (or NaNO 3 ), KIO 3 , HCOONa, CH 3 COONa (or K), C 6 H 5 COONa, C 6 H 5 SO 3 Na and p -CH 3 C 6 H 4 SO 3 Na solutions under a temperature difference and an osmotic pressure difference. Hydrocarbon-type anion-exchange membranes Neosepta® AM-1, Aciplex® A-201 and A-221, test membranes STA-1 to STA-5, and fluorocarbon-type anion-exchange membrane Tosflex® IE-DF 17 were used. The water content is represented by the unit: g H 2 O per g dry membrane without the weight of anhydrous counterions. Plots of the volume flux against the temperature difference of both side solutions gave straight lines starting from zero. The direction of thermoosmosis was from the cold to the hot side. The order of water content of membranes is F − >IO − 3 >Cl − >NO − 3 for inorganic ions and CH 3 COO − >HCOO − >C 6 H 5 COO − > p -CH 3 C 6 H 4 SO − 3 (or C 6 H 5 SO − 3 ) for organic ions regardless of the type of membrane. The order of the absolute value of the entropy difference between transported entropy in membranes and partial molar entropy of water in the external solutions is IO − 3 >F − >Cl − >NO − 3 for inorganic ions and C 6 H 5 COO − >CH 3 COO − >HCOO − for organic ions for all membranes.

Thermal membrane potential across cation-exchange membranes was measured for various halide solutions. Linear relationships between thermal membrane potential (ΔΨ) and temperature difference (ΔT) were observed, and the temperature coefficient of thermal membrane potential (ΔΨ/ΔT) decreases with increase in the molality of the external solution as predicted by a theory reported. When counterions of membranes are hydrogen ions, the sign of the coefficients turns into minus near 0.01 mol/kg of the external solution for all membranes, although the coefficients are always positive for all the other forms. The dependence of the coefficients on the molality of the external solutions sometimes deviated slightly from the theory. This deviation is attributed to some change in water content of the membranes. A reproducible method of measuring water content of membranes was applied to discuss the change in the state of the membranes.

An improved thermal membrane potential cell was constructed with blocks of poly (vinyl chloride). In the new cell the membrane was used as a ribbon with the two contacts to the external solutions on opposite sides and separated by 0 to 10 mm. Thermal membrane potentials across test anion-exchange membranes Aciplex STA-1 to 5, of which the thickness is about 0.1 mm, were measured using the new cell. The transported entropy of counterions in the membranes was estimated from experimental data for thermal membrane potential, electroosmosis and thermoosmosis. Thermal membrane potentials across STA-2 to 5 were nearly equal to each other regardless of the differences in the water content, the ion-exchange capacity and the DVB content. However, the difference between the mean molar transported entropy of counterions and the partial molar entropy of the ions in the external solutions (s_-s_), which reflects to the stability of counterions in the membrane, decreases roughly with decrease in the water content or with increase in the molality of fixed charges in the membrane. The absolute values of thermal membrane potentials across STA-3 increased in the order of I->Cl-≈Br->IO3->F-≈CH3COO- ion forms.

Solvent transport across anion-exchange membranes was measured for water and aqueous KCl, KF, KIO 3 , KClO 3 , HCOONa, CH 3 COOK, C 2 H 5 COONa, C 6 H 5 COONa, C 6 H 5 SO 3 Na solutions under a temperature difference and an osmotic pressure difference. Anion-exchange membranes Neosepta® AFN and modified porous AFN(P) were used. The porous membrane AFN(P) was prepared by treating Neosepta® AFN with NaOH solution. Plots of the volume flux against the temperature difference between the solutions on both sides give straight lines starting from zero. The direction of thermoosmosis was from the cold side to the hot side. Solvent transport across anion-exchange membranes under a temperature difference and an osmotic pressure difference is proportional to the water content of the membranes that is represented by the weight of absorbed water per one gram of dry membrane matrix without counterions, and is almost independent of the counterion species.

The time dependence of the streaming potential across collodion membranes, oxidized collodion membranes and interpolymer membranes of collodion and poly (acrylic acid) was measured and analyzed in detail as relaxation phenomena with plural components. The number of components of the relaxation varies with the membrane: one for collodion membranes, two for oxidized collodion membranes, and three components for collodion-poly(acrylic acid) membranes, respectively. Each relaxation component was assigned to the chemical component of the membrane: relaxation times are approximately 200, 50 and 10 sec for poly(acrylic acid), collodion and oxidized collodion, respectively. The effects of cross-linking, concentration of the external solution and temperature on each relaxation component were also explored.

The dependence of streaming potential on time was measured by applying a pressure difference across collodion-poly(acrylic acid) membranes, collodion-poly(acrylic acid) membranes partially complexed with Fe(II), and poly (styrenesulfonic acid) -type cation-exchange membranes. It has become apparent that the time dependence of the streaming potential reflects the relaxation phenomena of the polymer chains dissolved in the liquid phase of the membranes. The relaxation time becomes longer, the more flexible and longer are the polymer chains dissolved in the liquid phase.

Electrochemical analysis is considered to be applicable to the transport phenomena across a membrane which accompanies ionic reactions in the system where two solutions on both sides of the membrane are acidic and basic, respectively. Transport of halide ions across poly (vinylpyridine-co-styrene) membranes was analyzed by measuring the time dependence of the membrane resistance and bi-ionic potential. As a result, it becomes clear that poly (2-vinylpyridine-co-styrene) membranes are permselective for Cl- because HCl forms more easily pyridinium salt than HBr, and also that poly (4-vinylpyridine-co-styrene) membranes are permselective for Br- because the mobility of Br- is higher than that of Cl- in the membranes.