Unlock instant, AI-driven research and patent intelligence for your innovation.

Method for producing polyvinylidene fluoride porous membrane

A polyvinylidene fluoride, porous membrane technology, applied in the field of material science, can solve the problems of loose packing of polyvinylidene fluoride pellets, poor strength, uneven membrane pore structure, etc., to improve elongation and toughness, and high mechanical strength. , The effect of good water permeability

Inactive Publication Date: 2008-10-29
TSINGHUA UNIV
View PDF1 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

By adopting the method of the present invention, the problems of loose accumulation of polyvinylidene fluoride spheres, uneven membrane pore structure, and poor strength can be solved, and the polyvinylidene fluoride prepared within the concentration range of the polymer solution commonly used in membrane separation technology is realized. The polyvinylidene fluoride porous membrane can still maintain a uniform and continuous sponge-like structure, which greatly broadens the application range of polyvinylidene fluoride porous membrane in membrane separation technology

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for producing polyvinylidene fluoride porous membrane
  • Method for producing polyvinylidene fluoride porous membrane
  • Method for producing polyvinylidene fluoride porous membrane

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0022] a. The polyvinylidene fluoride diphenyl carbonate mixture with a polymer concentration of 30wt.%, sealed in a test tube filled with argon, placed in an oven at 200°C, fully dissolved for 24 hours, stopped heating, degassed for 30s, and statically Place, and make casting solution;

[0023] b. Form the above-mentioned casting liquid into a film on a glass sheet at the same temperature, with a film thickness of 200 μm;

[0024] c. Place the glass flake in tap water at 0°C for 2 hours, so that the liquid-liquid phase separation occurs first in the casting solution, and then polyvinylidene fluoride crystallizes to fix the membrane structure;

[0025] d. Put the glass slice carrying the film into absolute ethanol at 60° C. to extract diphenyl carbonate. Ethanol was changed every 12 h for two changes.

[0026] e. Remove the polyvinylidene fluoride film from the glass sheet in a wet state, place it in the air, and let it dry.

[0027] The fracture surface (liquid nitrogen fr...

Embodiment 2

[0029] a. The polyvinylidene fluoride diphenyl carbonate mixture with a polymer concentration of 40wt.%, sealed in a test tube filled with argon, placed in an oven at 180°C, fully dissolved for 24 hours, stopped heating, degassed for 30s, and statically Place, and make casting solution;

[0030] b. Form the above-mentioned casting liquid into a film on a glass sheet at the same temperature, with a film thickness of 200 μm;

[0031] c. Place the glass flake in tap water at 50°C for 2 hours, so that the liquid-liquid phase separation occurs first in the casting solution, and then polyvinylidene fluoride crystallizes to fix the film structure;

[0032] d. Put the glass slice carrying the film into absolute ethanol at 90° C. to extract diphenyl carbonate. Ethanol was changed every 12 h for two changes.

[0033] e. Remove the polyvinylidene fluoride film from the glass sheet in a wet state, place it in the air, and let it dry.

[0034] The fracture surface (liquid nitrogen freez...

Embodiment 3

[0036] a. The polyvinylidene fluoride diphenyl carbonate mixture with a polymer concentration of 60wt.%, sealed in a test tube filled with argon, placed in an oven at 160°C, fully dissolved for 24 hours, stopped heating, degassed for 60s, and statically Place, and make casting solution;

[0037] b. Form the above-mentioned casting liquid into a film on a glass sheet at the same temperature, with a film thickness of 200 μm;

[0038] c. Place the glass flake in tap water at 0°C for 2 hours, so that the liquid-liquid phase separation occurs first in the casting solution, and then polyvinylidene fluoride crystallizes to fix the membrane structure;

[0039] d. Put the glass flake carrying the film into methanol at 90° C. to extract diphenyl carbonate. Ethanol was changed every 12 h for two changes.

[0040] e. Remove the polyvinylidene fluoride film from the glass sheet in a wet state, place it in the air, and let it dry.

[0041] The fracture surface (liquid nitrogen freeze bri...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
pore sizeaaaaaaaaaa
pore sizeaaaaaaaaaa
pore sizeaaaaaaaaaa
Login to View More

Abstract

The present invention provides a preparation method of a PVDF porous membrane. The method includes the following steps: a composite solvent with 30wt.percent to 60wt.percent of PVDF, 70wt.percent to 40wt.percent of diphenyl carbonate or 30wt. percent to 60wt.percent of PVDF and 70wt.percent to 40wt.percent of diphenyl carbonate / benzophenone is added into a high-temperature container and heated under argon protection; after the solution is homogeneous and the heating is ceased, the solution is statically placed for deforming and prepared into a casting solution; the casting solution is poured onto a surface plate for molding and dipped in tap water for quenching so as to cause phase separation; PVDF crystal can fix the membrane structure; the formed membrane is put into an extracting agent for extracting the solvent, thus obtaining the PVDF porous membrane. The cross section structure of the PVDF porous membrane prepared by the present invention is an evenly communicated sponge structure.

Description

technical field [0001] The invention belongs to the field of material science and relates to a method for preparing polyvinylidene fluoride porous membrane. Background technique [0002] Membrane separation technology has attracted increasing attention due to its energy saving, simple equipment, convenient operation, and no pollution, and has become an effective technology to replace traditional separation methods. Membrane materials in membrane separation technology involve polymer chemistry and polymer physics, and the development of membrane materials is a key aspect of membrane separation technology. [0003] Polyvinylidene fluoride is a thermoplastic semi-crystalline high polymer, which is formed by homopolymerization of vinylidene fluoride or copolymerization of vinylidene fluoride and hexafluoropropylene. Its molecular chain is regular and easy to crystallize. Polyvinylidene fluoride has outstanding characteristics of solvent resistance, oxidation resistance, ultravi...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): B01D71/34B01D69/06
CPCB01D71/34B01D2323/12B01D67/002
Inventor 王晓琳林亚凯唐元晖杨健尚伟娟
Owner TSINGHUA UNIV
Features
  • R&D
  • Intellectual Property
  • Life Sciences
  • Materials
  • Tech Scout
Why Patsnap Eureka
  • Unparalleled Data Quality
  • Higher Quality Content
  • 60% Fewer Hallucinations
Social media
Patsnap Eureka Blog
Learn More

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2025 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com