Check patentability & draft patents in minutes with Patsnap Eureka AI!

Microporous membrane made from polyolefin

A polyolefin microporous membrane, membrane thickness technology, applied in membrane, membrane technology, semi-permeable membrane separation and other directions, to achieve the effect of excellent strength and safety, high capacity

Active Publication Date: 2007-01-17
ASAHI KASEI KK
View PDF6 Cites 14 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0016] As described above, microporous membranes for electronic parts that are high in strength and safety and have high permeability when the separator becomes thinner, methods of producing such microporous membranes, and the use of separators having these characteristics have not yet been obtained. A non-aqueous electrolyte battery with high capacity, long life and high safety

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
  • Microporous membrane made from polyolefin
  • Microporous membrane made from polyolefin
  • Microporous membrane made from polyolefin

Examples

Experimental program
Comparison scheme
Effect test

example

[0048] (a) mixing polyolefin resin, plasticizer, inorganic powder and additives in a Henschel mixer or the like and granulating the mixture;

[0049] (b) melt-kneading the mixture obtained in step (a) on an extruder having a T-die mounted on its leading edge;

[0050] (c) forming the kneaded material obtained in step (b) into a sheet by extruding the kneaded material from a T-die, rolling the extruded material from both sides with a hot roller, and then cooling;

[0051] (d) extracting and removing plasticizer and inorganic powder from said shaped article in sheet form, followed by drying; and

[0052] (e) stretching said shaped article in sheet form at least uniaxially and subjecting it to heat treatment.

[0053] Examples of inorganic powders that can be used in step (a) of the production method of the present invention include: silicon dioxide, calcium silicate, aluminum silicate, alumina, calcium carbonate, magnesium carbonate, kaolin, talc, titanium oxide, carbon black ...

Embodiment 1

[0138] 20% by weight of silica powder A (prepared by a dry method, the average dispersed particle size is 0.25 μm, the cumulative dispersed particle size of 95% by volume is 0.45 μm, the cumulative dispersed particle size of 5% by volume is 0.15 μm, the cumulative dispersed particle size The particle diameter ratio is 3.0, the oil absorption is 240ml / 100g, and the primary particle diameter is 12nm (see Table 1)), 19.2% by weight of ultra-high molecular weight polyethylene ([η] is 7.0dl / g), 12.8% by weight of High-density polyethylene ([η] of 2.8 dl / g) and 48% by weight of dioctyl phosphate (DOP) were mixed and pelletized. The granulated mixture was then kneaded and extruded into a 90 μm thick sheet using a twin-screw extruder equipped with a T-die. From this molded sheet, DOP was extracted and removed with dichloromethane, and silica powder was additionally extracted and removed with sodium hydroxide, thereby preparing a microporous membrane. Two microporous membrane sheets w...

Embodiment 2

[0140] Two film sheets obtained in the same manner as in Example 1, in which the silica powder has been extracted, were stacked, stretched 5.0 times longitudinally while heating at 115°C, and stretched transversely while heating at 133°C. Stretch 2.2 times. The physical properties of the obtained films are shown in Table 2.

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
thicknessaaaaaaaaaa
pore sizeaaaaaaaaaa
strengthaaaaaaaaaa
Login to View More

Abstract

Disclosed is a microporous membrane made from a polyolefin wherein the thickness is 1-30 µm, the porosity is 30-60%, the air permeability is 50-250 sec / 100 cc, the puncture strength is 3.5-20.0 N / 20 µm, the maximum pore diameter determined by a bubble point method is 0.08-0.20 µm, and the ratio between the maximum pore diameter and the average pore diameter (maximum pore diameter / average pore diameter) is 1.00-1.40. Since this microporous membrane made from a polyolefin is highly safe while maintaining a high permeability, it is useful especially as a separator for recent small-sized, high-capacity nonaqueous electrolyte batteries.

Description

technical field [0001] The present invention relates to a polyolefin microporous membrane with good permeability as well as excellent strength and safety and a method for preparing the membrane. Specifically, the present invention relates to a polyolefin microporous membrane useful as a separator for electronic parts, particularly high-capacity, long-life nonaqueous electrolyte batteries, a method for producing the membrane, and a nonaqueous electrolyte battery. Background technique [0002] Polyolefin microporous membranes have hitherto been widely used as microfiltration membranes, battery separators or capacitor separators. Especially in recent years, it has been frequently used as a separator for lithium ion secondary batteries. Currently, as power consumption increases, lithium ion secondary batteries with high capacity, high power, and long life have been required. [0003] In this case, separators for lithium ion secondary batteries need to have high permeability in...

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): C08J9/00C08J9/26H01M2/16H01M10/40C08L23/00B01D67/00B01D69/02B01D71/26H01M4/131H01M4/133H01M10/0525H01M10/36H01M50/417H01M50/489
CPCH01M4/133B01D2323/20H01M4/131H01M10/0525B01D2325/04H01M2/1653B01D67/003B01D67/0018B01D67/0027B01D2325/02Y02E60/122B01D67/0011B01D71/26B01D69/02B01D2325/20Y10T428/249978Y02E60/10H01M50/417H01M50/489B01D71/261B01D2325/02834B01D71/262C08J9/00C08J5/22C08F10/00H01M4/13
Inventor 池本贵志河添慎也
Owner ASAHI KASEI KK
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