Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Electroconductive aramid paper

Inactive Publication Date: 2006-11-30
EI DU PONT DE NEMOURS & CO
View PDF15 Cites 26 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

[0011] This invention relates to aramid paper comprising 5 to 65 parts by weight aramid fiber, 30-90 parts by weight aramid fibrids, and 1-20 parts by weight of conductive fille

Problems solved by technology

However, it has been found that this paper does not have adequate tensile strength for automated tape winding of conductors, resulting in breakage and tearing of aramid tapes when wrapped using the under the tensions normally used by automatic winding devices.
The hot calendered version of this paper has an improved tensile strength of about 35 N / cm (a tensile index about 90 N*m / g) and is strong enough for the automated tape winding; however, this calendered paper is less saturable and less formable, because after calendering the resulting paper is denser (about 0.64 g / cm3).
At the same time, calendering or hot compression significantly changes the electrical properties of the paper, as well as reducing its free volume and ability to be saturated and impregnated by a resin.

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

Examples

Experimental program
Comparison scheme
Effect test

example 1

[0047] An aqueous dispersion was made of never-dried poly (metaphenylene isophthalamide) (MPD-I) fibrids at a 0.5% consistency (0.5 weight percent solid materials in water). Carbon fiber was added to this dispersion. After about ten minutes of continued agitation, additional water and meta-aramid floc were added with additional agitation of about ten minutes to completely blend the materials and to yield a slurry having a final consistency of 0.35%. The final slurry was comprised of the following solids by weight: 39% MPD-I floc, 50% MPD-I fibrids, and 11% carbon fiber.

[0048] The MPD-I fibrids were made using the general method as disclosed and described in U.S. Pat. No. 3,756,908. The MPD-I floc had a linear density of 0.22 tex (2.0 denier), a cut length of 0.64 cm, and an initial modulus of about 800 cN / tex (sold by DuPont under the trade name NOMEX®). The carbon fiber was FORTAFIL fiber type 150 (length of 0.32 cm), available from FORTAFIL Inc.

[0049] The slurry was pumped to a ...

example 2

[0050] A slurry was prepared as in Example 1, however the final slurry was comprised of the following solids by weight: 40% MPD-I floc, 50% MPD-I fibrids, and 10% carbon fiber. A paper with a basis weight of 50.2 g / m2 was formed on a Fourdrinier and additionally heat-treated as in Example 1. A 2 cm wide tape from this paper was successfully wrapped without breakage or tearing on a coil using an automated winding process.

example 3

[0051] A slurry was prepared as in Example 1, however the final slurry was comprised of the following solids by weight: 44% MPD-I floc, 50% MPD-I fibrids, and 6% carbon fiber. A paper with a basis weight of 53.9 g / m2 was formed on a Fourdrinier and additionally heat-treated as in Example 1. A 2 cm wide tape from this paper was successfully wrapped without breakage or tearing on a coil using an automated winding process.

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
Percent by massaaaaaaaaaa
Percent by massaaaaaaaaaa
Percent by massaaaaaaaaaa
Login to View More

Abstract

This invention relates to aramid papers, and a process for making such papers, the papers comprising 5 to 65 parts by weight aramid fiber, 30-90 parts by weight aramid fibrids, and 1-20 parts by weight of conductive filler, based on the total weight of the aramid fiber, fibrids, and filler; the papers having an apparent density of not more than 0.43 g / cm3 and a tensile index not less than 60 Nm / g.

Description

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] This invention relates to electroconductive aramid paper suitable for electrostatic discharge interference and / or electromagnetic interference shielding. [0003] 2. Description of Related Art [0004] NOMEX® Type 843 Conductive Carbon Blend aramid paper consists of NOMEX® brand floc and fibrids blended with conductive carbon fibers. This paper has been available in both hot calendered and uncalendered versions. The uncalendered version of this paper has a basis weight of about 40 g / m2, a density of about 0.29 g / cm3, and a tensile strength of about 16 N / cm, which corresponds to tensile index of 40 N*m / g, and can be easily saturated with polymer resins. However, it has been found that this paper does not have adequate tensile strength for automated tape winding of conductors, resulting in breakage and tearing of aramid tapes when wrapped using the under the tensions normally used by automatic winding devices. The hot cal...

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
IPC IPC(8): D21H13/26D21H13/36
CPCD21H13/50D21H13/26
Inventor LEVIT, MIKHAIL R.
Owner EI DU PONT DE NEMOURS & CO
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com