A kind of polytetrafluoroethylene microfiber membrane

Abstract

Polytetrafluoroethylene ultra-fine fiber tubular membrane comprising a polytetrafluoroethylene material body; the polytetrafluoroethylene has a fiber shape and the fiber has a diameter of 30-200 nm; the body has pore cavities of a pore diameter of 10-1000 nm and cavity walls formed by three-dimensional spaces surrounding the pore cavities; the pore cavities are uniformly distributed and each pore cavity is three-dimensionally open; the porosity is ≥75%, the tensile strength is 15 N / mm2 or higher, and the water resistance pressure is 3 kg / cm2 or higher.

Description

technical field [0001] The invention relates to a porous material, in particular to a polytetrafluoroethylene fiber membrane, which is especially suitable for membrane distillation. Background technique [0002] A solid containing a certain number of holes is called a porous material, which is a material with a network structure composed of through or closed holes. Compared with continuous medium materials, porous materials generally have the advantages of low relative density, high specific strength, high specific surface area, light weight, sound insulation, heat insulation, and good permeability. According to the different pore size, porous materials can be divided into microporous (pore size less than 2 nm) materials, mesoporous (pore size 2-50 nm) materials and macroporous (pore size greater than 50 nm) materials. [0003] Porous materials can be divided into metallic porous materials and non-metallic porous materials according to their material. Non-metallic porous m...

AI Technical Summary

Problems solved by technology

However, due to the randomness and irregularity of the pore structure, it still cannot meet the performance requirements of many applications.

[0004] In many applications, it is required that the porous material itself is uniform, the pore size and the distribution of the pores are uniform, so that the performance is uniform, but in fact, many porous materials do not meet this requirement, and their uniformity complements; although some materials claim to be Higher uniformity has been achieved, but its uniformity is still the uniformity at the large volume scale. If it is measured with a small volume scale, for example, a plurality of three-dimensional bodies whose volume is not larger than one cubic centimeter are randomly selected on the material, and their volumes are measured respectively. Quality, the difference in uniformity is still very large, so the various properties of PTFE porous membrane materials such as strength, elastic modulus, flux, etc. are not uniform, which seriously affects its function.