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

Modified expanded polytetrafluoroethylene, its preparation method, composite ion exchange membrane and its application

A polytetrafluoroethylene and composite ion technology, applied in the field of its preparation, modified expanded polytetrafluoroethylene, and composite ion exchange membrane, can solve the problems of e-PTFE stability and poor uniformity, and achieve good uniformity, good stability

Active Publication Date: 2022-02-22
STATE POWER INVESTMENT CORP HYDROGEN ENERGY CO LTD
View PDF15 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] The main purpose of the present invention is to provide modified e-PTFE, its preparation method, composite ion exchange membrane and its application, to solve the problems of poor stability and uniformity of e-PTFE in the prior art

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
  • Modified expanded polytetrafluoroethylene, its preparation method, composite ion exchange membrane and its application
  • Modified expanded polytetrafluoroethylene, its preparation method, composite ion exchange membrane and its application
  • Modified expanded polytetrafluoroethylene, its preparation method, composite ion exchange membrane and its application

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0032] In another typical embodiment of the present application, a preparation method of modified e-PTFE is provided, the preparation method includes: Step S1, impregnating and filling the freezing medium into the pores of e-PTFE to obtain wet material ; Step S2, crystallize at least part of the freezing medium in the wet material to obtain a solid material; Step S3, freeze-dry the solid material to obtain modified e-PTFE.

[0033] In this application, the freezing medium is impregnated and filled into the pores of e-PTFE. After the freezing medium is solidified into a solid, the crystals are highly oriented and the volume expands, and the e-PTFE also expands. The freeze-drying method is then used to remove the freezing medium, which can maintain the structural size of the porous material, thereby maintaining a structure similar to that in the filling state of the freezing medium after removing the freezing medium. The modified e-PTFE prepared by the method of the present appl...

Embodiment 1

[0062] 9 parts by mass of dimethyl sulfoxide and 1 part by mass of water were mixed at 25° C. to form a liquid freezing medium. Use a scraper to scrape the above-mentioned freezing medium, soak 0.05 parts by mass of e-PTFE-1 in the above-mentioned liquid freezing medium for 6 hours, make the liquid completely infiltrate and fill the pores of e-PTFE-1, and obtain wet material e-PTFE-1 . The wet material e-PTFE-1 was ice-crystallized at -30°C for 0.5 h to obtain a solid material. Put the solid material into the freeze-drying equipment, freeze-dry at 0.1Pa ~ 20Pa for 12 h. The initial freeze-drying temperature is -40°C, and the temperature rises slowly during the freeze-drying process at a rate of 5°C / h. After freeze-drying, the modified e-PTFE-1 is obtained. The contact angle between the modified e-PTFE-1 and the perfluorosulfonic acid resin solution at 16s is as follows: figure 2 shown. The properties of modified e-PTFE-1 are shown in Table 1.

Embodiment 2

[0064] The difference from Example 1 is that 1 part by mass of e-PTFE-1 is soaked in the above-mentioned liquid freezing medium.

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
porosityaaaaaaaaaa
thicknessaaaaaaaaaa
pore sizeaaaaaaaaaa
Login to View More

Abstract

The invention provides modified expanded polytetrafluoroethylene, its preparation method, composite ion exchange membrane and application thereof. The average pore diameter of the modified expanded polytetrafluoroethylene is 0.05 μm to 0.5 μm, and the porosity is 50% to 95%. The pore diameter of the modified expanded polytetrafluoroethylene exceeds 99% of the pores. Within ±10%, the dispersion coefficient of the modified expanded polytetrafluoroethylene is less than 10%. In this application, the pore size distribution of the modified e-PTFE is narrow, and the dispersion coefficient of the gram weight is less than 10%, so its uniformity is better, and when the average pore size and porosity are controlled within the above range, the modified expanded polytetrafluoroethylene Ethylene can still maintain good mechanical properties, so the stability is better.

Description

technical field [0001] The invention relates to the technical field of modified expanded polytetrafluoroethylene, in particular to modified expanded polytetrafluoroethylene, a preparation method thereof, a composite ion exchange membrane and applications thereof. Background technique [0002] At present, the ion exchange membranes of all vehicle fuel cells are prepared on the basis of perfluorosulfonic acid resin (PFSA), which is mainly determined by two factors: safety, reliability and full life cycle cost. DuPont took the lead in developing the first generation of PFSA ion exchange membrane commercial products in the 1990s, including Nafion112, Nafion115 and Nafion117. This generation of products adopts the melt extrusion process and has good stability and mechanical properties. The second-generation Nafion membrane adopts the solution casting membrane process to reduce the cost, such as Nafion211, Nafion212. In order to solve the problem of the large thickness of the io...

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 Patents(China)
IPC IPC(8): C08J9/40C08J9/26C08J5/22C08L27/18B01J47/00
CPCC08J9/40C08J9/26C08J5/2237B01J47/00C08J2327/18C08J2201/0482C08J2201/0484
Inventor 贾雯迪张泽天刘昊董天都刘一晨李道喜李丹周朝毅
Owner STATE POWER INVESTMENT CORP HYDROGEN ENERGY CO LTD