JPS6057898B2 - Cation exchanger having inclusion effect and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cation exchanger having an inclusion effect and a method for producing the same, and more specifically, the present invention relates to a cation exchanger having an inclusion effect and a method for producing the same. The present invention relates to an ion exchanger for dextrin resin and a method for producing the same.

Cyclodextrin has six or more glucose molecules α-1,
It is a 4-linked cyclic oligosaccharide that has a cylindrical cavity within its molecule, and forms clathrate compounds by incorporating various substances into the cavity. In order to form this clathrate, the shape and size of the molecule of the clathrate must fit into the cavity of the cyclodextrin, and depending on the degree of compatibility, there is a gap between the clathrate and the cyclodextrin. Because there are differences in the working affinity, it is possible to separate and divide various substances by utilizing these differences. Attempts are being made to use it as a filler in graphics. However, since the clathrate compound-forming effect of cyclodextrin mainly depends on the size and shape of the clathrated substances, when separating substances using polycyclodextrin resin obtained by polymerizing cyclodextrin, The more similar the sizes and shapes, the more difficult it is to separate them.

Therefore, in such a case, the mere effect of inclusion is insufficient for separation, and it is necessary to introduce some effect effective for separation. In view of these circumstances, the present inventors have conducted extensive research into improving polycyclodextrin resins, and have found that by introducing carboxymethyl groups into polycyclodextrin resins, polycyclodextrin resins can be simply clathrated. It not only has the function of an ion exchanger, but also has the effect of electrostatic interaction in addition to the size and shape of the substance, and therefore has the ability to separate substances due to the difference in charge distribution. The present invention was completed based on this knowledge.

The polycyclodextrin used in the present invention is α-
Cyclodextrin, β-cyclodextrin, γ-cyclodextrin, and mixtures thereof are crosslinked into polymers or bonded to polymers,
Any material that can withstand the reaction conditions for introducing a carboxymethyl group can be used.

In particular, polycyclodextrin resin crosslinked with epichlorohydrin or a diepoxy compound is suitable because it not only has high resistance to heat and alkali but also has a large number of hydroxyl groups for reacting with monohalogenoacetate. In order to introduce carboxymethyl groups into polycyclodextrin resin, monohalogenoacetate is added to polycyclodextrin dispersed in an alkaline aqueous solution.

The shape of the resin used includes pulverized solid polycyclodextrin resin and bead-shaped resin, but bead-shaped is preferable because the strength of the resin weakens when it swells in an alkaline aqueous solution. It will be done. The alkaline aqueous solution preferably has a concentration of 20 to 5 percent by volume of sodium hydroxide or potassium hydroxide, and is added in an amount of 3 to 1 part by volume per 1 part by weight of the polycyclodextrin resin. . As the monohalogenoacetate, alkali metal salts and alkaline earth metal salts of monochloroacetic acid, monobuteptamoacetic acid, and monoiodoacetic acid are used, and the amount is 0.0% per part by weight of the polycyclodextrin resin.
The amount is preferably in the range of 5 to 5 parts by weight, but may be less than 0.5 if the introduction rate of carboxymethyl groups is to be reduced. The monohalogenoacetate is used in powder form or as an aqueous solution.
In the case of an aqueous solution, if the concentration is low, the introduction rate of carboxymethyl groups decreases, so it is preferably 2% by weight or more. While stirring the polycyclodextrin resin dispersed in the alkaline aqueous solution, a monohalogenoacetate is added thereto, and the reaction is then carried out while maintaining the temperature at 40 to 60°C.

The stirring speed is preferably 100 to 500 rpm, and vigorous stirring is not preferred since it may crush the resin. The temperature may be outside the range of 40-6C), but 60C
If the temperature is higher than 'C, the resin will be colored, and if it is lower than 40°C, the introduction rate of carboxymethyl groups will be poor. The appropriate reaction time is 5 hours to 1 day. The obtained product is washed with distilled water until the pH of the washing water becomes neutral, dehydrated with acetone or alcohol, and dried to obtain an alkali metal salt or an alkaline earth metal salt. By washing this with dilute sulfuric acid, the cations are replaced with hydrogen ions, and it can be used as a cation exchanger. A feature of the present invention is that a cation exchanger having an inclusion effect can be obtained by introducing a carboxymethyl group into a polycyclodextrin resin, and the obtained resin can be used as an ion exchanger, a separating agent, and Can be used as an adsorbent.

Next, the present invention will be explained in more detail with reference to Reference Examples and Examples. Reference Example 12.5 Mt of water was added to 25 y of powdered β-cyclodextrin and kneaded, followed by 37.5 ml of 30% aqueous sodium hydroxide solution and 1 ml of sodium borohydride.
00mg to make a homogeneous solution and keep it at 50℃ for 20 minutes.
7.5 ml of epichlorohydrin was added dropwise while stirring at a speed of 0 rpm, and after stirring for 3 minutes, the mixture was kept at 50° C. for 30 minutes to eliminate bubbles.

Claims (1)

[Scope of Claims] 1. A cation exchanger having an inclusion effect, which is made of a polycyclodextrin resin having a carboxymethyl group. 2. A method for producing a cation exchanger having an inclusion effect, which comprises reacting a polycyclodextrin resin with a monohalogenoacetate.