JPS63291902A - Production of high polymer electrolytic composite - Google Patents

Abstract

PURPOSE:To produce a composite applicable in a wide range of uses even requiring chemical resistance and electrical conductivity, by reacting polyferric sulfate with polyvinyl sulfate in a specific acid concentration. CONSTITUTION:Polyferric sulfate, an inorganic high polymer electrolyte, is reacted with polyvinyl sulfate, an anionic high polymer electrolyte, in an acid concentration of pH1.2-2.3 usually at <=30 deg.C to give a high polymer electrolytic composite. The structure of the prepared composite is estimated as [Fe2(OH)2](polyvinyl sulfate)4 or [Fe2(OH)](polyvinyl sulfate)5. The composite shows not only ion selective permeability and active transporting properties but also chemical resistance which has not been found in an existing high polymer system and further is provided with electrical conductivity.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention utilizes polyferric sulfate (hereinafter referred to as PFS), which is an inorganic polymer electrolyte, and polyvinyl sulfate (hereinafter referred to as PvS), which is an anionic polymer electrolyte. Regarding the method of producing a polymer electrolyte complex (hereinafter referred to as PEC) by reacting with In addition, it exhibits chemical resistance not seen in conventional organic polymer systems, and is also electrically conductive, allowing it to be used in a wide range of applications that could not be used with conventional organic polymer systems. It is.

<Prior Art> PFS is a polybasic substance mainly used in general industrial wastewater treatment agents and has the general formula [Few(OR) n (S04) 3-n/2).

On the other hand, Pvs is a sulfate of polyvinyl alcohol, which is a synthetic polymer used for colloid titration, etc. This is, for example, its potassium salt, polyvinyl potassium sulfate (
It is also used as an alkali metal salt, such as PVSK.

By the way, PE has long been expected to have new uses such as biological membranes and various functional materials or biomaterials.
All of C were obtained by reacting an organic polycation and an organic polyanion. Examples include Japanese Patent Publication No. 53-41718, Japanese Patent Application Publication No. 60-156
There are techniques disclosed in Japanese Patent Publication No. 702, Japanese Unexamined Patent Publication No. 61-64701, and the like.

<Problem to be solved by the invention> Organic P as shown in the three patents cited above
EC is an excellent material for ultrafiltration membranes and dialysis membranes due to its unique properties such as active transport and permselectivity, but its durability against acids and alkaline solutions is poor. It is poorly suited for use in such an environment, and there is still room for improvement in terms of active transport and selective permeation, and there are still problems such as insufficient conductivity. Ta.

In the present invention, instead of the conventional organic-organic combination, P
The purpose of this invention is to synthesize EC and use the synthesized product to solve the problems that remain with the conventional PEC.

Means for Solving the Problems> The means for achieving the above object of the present invention are as follows. That is, PFS and pvs are reacted at a pH of 2 to 2.3, and PEC is obtained as a precipitated product.

Since the alkali metal salt of PvS of the present invention is easier to handle, commercially available polyvinyl potassium sulfate (hereinafter referred to as PVSK), which is a potassium salt, was used in the present invention.

The structure of PEC produced from commercially available PFS and the same PVSK varies depending on P' and other conditions, so it cannot be determined, but it is either (Few (OH) z) (PVS) 4 or [Fe, 2 (
OR)] (PVS)5.

In the above method of the present invention, the concentration of the PFS aqueous solution is Fe2
It is desirable that O3 be 5 g/I or less; if it exceeds 5 g/L, the yield of the product I'EC will be poor (and the reproducibility will also be poor).
Concentrations below g/l are preferred. In addition, the pit of the acid aqueous solution of PFS and PVSK was set in the range of 1.2 to 2.3 because
This is because if the pH is less than 1.2, PEC will dissolve and no precipitate will be formed, whereas if the pH exceeds 2.3, Fe(OH)3 will precipitate and PEC will not be able to be formed. Further, the type of acid used at this time is not particularly limited, and may be an inorganic acid or an organic acid as long as it does not react with PFS or PVSK.

Next, the temperature of the solution when reacting PFS and PVSK is preferably as low as possible; if the temperature exceeds 30°C, it will decompose and the desired PEC will not be obtained. Therefore, in order not to raise the temperature too much during dehydration and drying of the PEC, which is the precipitate, it is washed with an alcohol system that easily evaporates, and dried in a low temperature range.

<Example> Hereinafter, the present invention will be described in more detail while showing examples thereof.

In this example, aqueous solutions of PFS and PVSIC were prepared with a pH of 5 using an aqueous hydrochloric acid solution, and one solution was mixed with the other solution at 50 mj/30 at a constant temperature of 23°C.
, min to obtain a precipitate.

Immediately after generation, PEC is unstable, so it is left standing for 30 minutes, centrifuged, washed with methanol, and dried under reduced pressure at room temperature until it reaches a constant weight. Only those with an error in the amount produced within 3% of the average value are It was used in the following experiments.

Next, the film properties and conductivity of the obtained PEC were measured.

That is, the PEC obtained by the method of the present invention was mixed with 18±3% hydrochloric acid.
100g in a solvent of 40% 1,4-dioxane-balance water
The solution was dissolved to a concentration of 7/J, cast on a Teflon sheet, and dried at a temperature of 30° C. and 51° C. 50% to form a film. The thickness of the obtained film was 100±20 μm.

The membrane thus obtained had an active transport rate of 10% and a selective permeation of 1.1.

Note that the active transport rate is O, IN NaCJ + O, IN I (CI and O
, IN NaOH (lNa"1max-INm"
lo)/fNa" loX 100 (%), the selective permeation was performed using Q, lN1 (CJ and 0.05N KOH+0) on both the left and right sides of the PEC membrane, respectively.
, 05N NaOH was added and determined from . However, 9.0 is the initial concentration on the right side, L and O are the initial concentrations on the left side, I2. Ltj is the right after each e time.

This is the concentration on the left.

Comparing this with conventional organic PEC, the active transport rate of 2-poly(3-vinyl-1,4-butyllactone-acrylonitrile l) is 10-12%, and the selective permeation is 1.4.
, glycol chitosan (hereinafter referred to as GC) + PVSK has an active transport rate of 10.2% and a selective permeation of 1.2, whereas the PEC obtained by the method of the present invention has an active transport rate that is not much different from that of the conventional method. It can be seen that it has a selective transmission function.

Moreover, PEC1191 obtained in the above-mentioned example of the present invention! The specific conductivity K (cm −'·fl−') of the material was 9.5×10 −′ when dry, and it was confirmed that the material had a property of considerably conducting electricity.

Next, in order to investigate the acid resistance and alkali resistance of the above PEC film,
p[(Fe9.2% generated under the conditions of 1,5, S 1
As a result of immersing PEC with a composition of 7.5% in hydrochloric acid and sodium hydroxide solution, it was stable for more than 72 days in INHC4 and stable for 2 days in fN NaOH, which was conventionally considered to have high chemical resistance. Organic PEC Teal GC + PVSK Ka, Q, IN HC
It was found that the chemical resistance was greater than that of I TE, which was stable within 351 days, and O, IN NaOH, which was stable within 1 day.

<Effects of the Invention> As described above, according to the present invention, it is possible to obtain an electrolyte complex consisting of a novel inorganic-organic combination that is completely different from conventional organic polymer electrolyte complexes. The product has the same active transport properties and permselectivity as conventional organic materials, and has particularly strong acid and alkali resistance, as well as electrical conductivity. It can be used in a wide range of new applications, such as applications that require chemical resistance and conductivity, as well as applications for various functional substances that previously used organic materials. be.

Claims (1)

[Claims] 1. Polyferric sulfate and polyvinyl sulfate at pH 1
．． A method for producing a polymer electrolyte complex, characterized by carrying out the reaction at an acid concentration of 2 to 2.3.