Preparation method of super-hydrophobic PVDF (polyvinylidene fluoride) membrane with micro-nano structure

A microstructure and super-hydrophobic technology, which is applied in the field of super-hydrophobic PVDF membrane preparation, can solve the problems such as the decline of system operation effect, achieve the effect of improving anti-wetting performance, simple preparation method and low cost

Inactive Publication Date: 2018-06-05
TIANJIN POLYTECHNIC UNIV
View PDF6 Cites 9 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In the process of membrane distillation, membrane absorption, etc., membrane wetting is a process that gradually evolves from the surface to the inside Rapid development, resulting in a sharp decline in system performance

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
  • Preparation method of super-hydrophobic PVDF (polyvinylidene fluoride) membrane with micro-nano structure
  • Preparation method of super-hydrophobic PVDF (polyvinylidene fluoride) membrane with micro-nano structure
  • Preparation method of super-hydrophobic PVDF (polyvinylidene fluoride) membrane with micro-nano structure

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0024] A preparation method of superhydrophobic PVDF membrane with micro-nano double microstructure, including the following steps:

[0025] (1) Configure casting solution: 1.7g of dried TiO 2 The nanoparticles were put into 73mL of N-methylpyrrolidone, 0.86mL of PEG-400 was added, and stirred to make TiO 2 Disperse the nanoparticles to obtain a suspension, put 17g of dry PVDF (polyvinylidene fluoride) powder into the suspension, stir in a 60°C constant temperature water bath for 12 hours to make it uniform, and stand for 12 hours to defoam to obtain a casting liquid;

[0026] (2) Put the casting liquid obtained in step (1) on a glass support plate and scrape it with a film scraper to make a nascent flat film with a thickness of about 200μm. It will stay in the air at 28°C and a relative humidity of 60% for 60s. Into a methanol aqueous solution with a volume concentration of 75% to complete the phase inversion; wash with tap water, soak in tap water for 72 hours, replace the tap wat...

Embodiment 2

[0029] A preparation method of superhydrophobic PVDF membrane with micro-nano double microstructure, including the following steps:

[0030] (1) Configure casting liquid: 1.95g dried SiO 2 The nanoparticles were put into 81mL of N,N-dimethylformamide, 4.3mL of PEG-600 was added, and stirred to make SiO 2 Disperse the nanoparticles to obtain a suspension, put 13g of dry PVDF powder into the suspension, stir for 8h in a constant temperature water bath at 70°C for 8h, and let stand for 8h to defoam to obtain a casting liquid;

[0031] (2) Place the casting liquid obtained in step (1) on a glass support plate and scrape it with a film scraper to produce a nascent flat film with a thickness of about 200 μm. Leave it in the air at 30°C and a relative humidity of 70% for 30 seconds. Into the ethanol aqueous solution with a volume concentration of 95% to complete the phase inversion; wash with tap water, soak in tap water for 72 hours, replace the tap water every 12 hours during the period,...

Embodiment 3

[0034] A preparation method of superhydrophobic PVDF membrane with micro-nano double microstructure, including the following steps:

[0035] (1) Configure casting solution: 0.5g dried TiO 2 The nanoparticles were put into 75mL N,N-dimethylformamide, 1mL PVP was added, and stirred to make TiO 2 Disperse the nanoparticles to obtain a suspension, put 10g of dry PVDF powder into the suspension, stir in a 60°C constant temperature water bath for 12 hours for uniformity, and stand for 12 hours to defoam to obtain a casting liquid;

[0036] (2) Place the casting liquid obtained in step (1) on a glass support plate and scrape a nascent flat film with a thickness of about 200 μm with a film scraper, and stay in the air at 25°C and 40% relative humidity for 60 seconds, Into a 50% volume concentration of n-propanol (isopropanol) aqueous solution to complete the phase conversion; wash with tap water, soak in tap water for 24 hours, during which time the tap water is replaced every 12 hours, and...

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

No PUM Login to view more

Abstract

The invention discloses a preparation method of a super-hydrophobic PVDF (polyvinylidene fluoride) membrane with a micro-nano structure. The preparation method comprises the steps of: (1) preparing membrane casting liquid: putting hydrophobic inorganic nano particles in a polar aprotic solvent, adding a pore-foaming agent for stirring to form a suspension, adding PVDF powder into the suspension, performing uniform stirring in a thermostatic waterbath, standing and defoaming to form the membrane casting liquid, and (2) performing membrane casting liquid striking-up to form a nascent flat sheetmembrane or spinning to form a nascent hollow fiber membrane yarn, remaining in air, putting in an alcohol aqueous solution for phase inversion and performing water cleaning, soaking and drying. The surface and internal walls of pore channels of the membrane prepared have the micro-nano structures, so that super-hydrophobicity of the surface and the internal walls of pores of the membrane is achieved; the wettability resistance of the membrane is improved entirely; and the membrane is applicable to the fields of membrane distillation, support liquid membranes, permeation distillation, membraneabsorption and the like. In addition, the preparation method of the super-hydrophobic membrane is simple, flexible, low in cost and applicable to the preparation of flat sheet membranes and hollow fiber membranes.

Description

Technical field [0001] The invention relates to the technical field of membranes, in particular to a method for preparing a superhydrophobic PVDF (polyvinylidene fluoride) membrane with a micro-nano double microstructure. Background technique [0002] A superhydrophobic surface is a surface with a contact angle with water greater than 150° and a rolling angle less than 10°. Its anti-pollution, anti-adhesion, and anti-wetting properties have attracted widespread attention. The materials used to prepare superhydrophobic surfaces generally have low surface energy chemical components. Commonly used hydrophobic materials include polypropylene (PP), polyethylene (PE), polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE) and polyethersulfone (PES). The critical surface tension of fluorine-containing compounds is significantly smaller than other compounds, so PVDF and PTFE have obvious advantages as hydrophobic materials. However, PTFE is not soluble in any solvent, and curr...

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): B01D67/00B01D69/08B01D71/34D01F1/08
CPCB01D67/0011B01D67/0013B01D67/0016B01D69/08B01D71/34B01D2325/38D01F1/08
Inventor 王亮赵斌张朝晖李振兴吴晓娜王虹利李君敬张宏伟冉沁灵
Owner TIANJIN POLYTECHNIC UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products