Homogeneous anion-exchange membrane and preparation method thereof

Abstract

The invention discloses a homogeneous anion-exchange membrane and a preparation method thereof. The preparation method is characterized by comprising the following steps: performing a reaction to obtain a uniform membrane liquid by taking chloromethylated vinyl benzene, vinyl benzene or / and alkyl vinyl benzene as a monomer, divinylbenzene as a crosslinking agent, benzoyl peroxide or azodiisobutyronitrile as an initiator, and quaternized bromomethylated poly(1, 4-dimethyl-2, 6-phenylene oxide) or quaternized chloracetylated poly(1, 4-dimethyl-2, 6-phenylene oxide) as a high molecular enhancer; carrying out a reaction to obtain a uniform membrane liquid and drying the membrane to obtain the anion-exchange membrane. The anion-exchange membrane is high in exchange capacity, good in electrochemical property, uniform in structure and good in heat resistance. As a previous functionalized reaction process is adopted without post-treatment steps, the membrane liquid is uniform and easy to coat, so that the membrane-forming property is good. The anion-exchange membrane obtained is high in mechanical strength, and the ion exchange radicals are uniformly distributed. Products in different structural forms and functions can be obtained by adjusting the content of polymers, types of solvents, quaterisation temperature and time and degree of crosslinking and changing the types of supporters.

Description

technical field [0001] The invention belongs to the technical field of membranes, and in particular relates to a homogeneous anion exchange membrane and a flow casting method preparation route thereof. Background technique [0002] Anion exchange membranes are widely used in electrodialysis, diffusion dialysis, membrane electrolysis, fuel cells, electrochemical sensors, etc., and their development and improvement have always attracted the attention of the theoretical and industrial circles. Homogeneous anion exchange membranes are more widely used in electrodialysis and proton exchange membranes because of the chemical bonds between the fixed groups and the main body of the membrane phase, which have the advantages of uniform structure and low resistance. [0003] Chinese patent ZL90103412.6 discloses a paste method for preparing anion exchange membranes, which consists of alkylene acrylates or alkylene oxides (monomers), divinylbenzene, etc. (crosslinking agent), Polyvinyl...

AI Technical Summary

Problems solved by technology

The steps of this method are complicated, and the quaternization process of soaking trimethylamine and ethylenediamine aqueous solution will destroy the original structure of the base membrane, resulting in low strength of the ionic membrane, and there may be small cracks that affect the membrane performance.

Moreover, this quaternization reaction by soaking is a solid-liquid heterogeneous reaction, which is carried out through the erosion and penetration of amines, which will cause uneven distribution of ion groups in the obtained membrane.

[0005] The above methods for preparing anion-exchange membranes all use the post-functionalization route of forming the basement membrane and then soaking in the aqueous solution of amine for quaternization. This method will destroy the structure of the basement membrane and also make the distribution of ion-exchange groups in the membrane uneven. In turn, it affects the performance of the membrane, which greatly limits the application of the membrane in diffusion dialysis, electrodialysis and other applications.

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