Narrow pore size distributed hydrophilic filtering membrane sensitive to temperature and pH and preparation method thereof

Abstract

For the problems that a large quantity of organic solvents and pore-foaming agents which are difficult to recycle are used in the traditional membrane preparing process, environmental contamination is caused, the pore size distribution of membranes is wide, and the membranes lack of responsiveness, the invention provides a narrow pore size distributed hydrophilic filtering membrane sensitive to temperature and pH on the basis of the idea of bionics by taking a metal chloride saline solution as the solvent. A preparation method of the membrane comprises the steps that fibroin is grafted with polyacrylonitrile and poly(N-isopropylacrylamide) in a homogeneous mode, and a membrane casting solution is obtained; the membrane casting solution is put into a water coagulating bath, metal ions and chloride ions are gradually scattered in water, an the fibroin grafted with poly(N-isopropylacrylamide) and polyacrylonitrile is subjected to phase transformation to form the membrane. The metal ions and the chloride ions play the role of hole forming, the fibroin, poly(N-isopropylacrylamide) and polyacrylonitrile are subjected to microphase separation, and water channels subjected to ion hole forming are formed in the interface. By means of the fibroin and poly(N-isopropylacrylamide), the pH value sensitivity and temperature sensitivity of the membrane are achieved. By means of the hole forming effect of the metal ions and the chloride ions, the hole size of the membrane is smaller, and the hole size distribution is narrow.

Description

technical field [0001] The invention relates to a temperature- and pH-sensitive narrow pore size distribution hydrophilic filter membrane and a preparation method thereof, belonging to the field of polymer materials and membranes. Background technique [0002] Membrane technology has been widely used in water treatment due to its advantages of high efficiency, low energy consumption and low investment cost. Membrane materials in the traditional sense that have been used in production cannot respond to changes in the environment, and the pore size of the membrane will not change with changes in the environment. When separating multi-component substances with different molecular weights, it is often necessary to use different pore sizes. Several types of filter membranes in China can only obtain the required components through multiple filtrations, which complicates the separation process, increases production costs, and affects the modernization process of separation. Theref...

AI Technical Summary

Problems solved by technology

[0006] Aiming at the deficiencies of the prior art, the technical problem to be solved by the present invention is that the use of organic solvents in the membrane making process inevitably causes environmental pollution, the membrane pore size distribution is wide, the membrane lacks responsiveness and is easy to pollute, etc.

[0007] The technical solution of the present invention to solve the problems of environmental pollution caused by the inevitable use of organic solvents in the membrane-making process, wide membrane pore size distribution, lack of responsiveness and easy pollution of the membrane is to design a temperature- and pH-sensitive narrow pore size distribution hydrophilic filter membrane