Pyrograf III Carbon Nanofibers: Properties and Applications of Type PR-19 Nanofibers

By AZoNano

Table of Contents

Introduction
PR-19-XT-PS Data Sheet
     Product nomenclature
PR-19-XT-LHT Data Sheet
     Product Nomenclature
PR-19-XT-HHT Data Sheet
     Product Nomenclature
About Pyrograf

Introduction

Pyrograf-III is a very fine, patented, inexpensive, highly graphitic carbon nanofiber. Pyrograf-III is offered in two fiber types having diameters ranging between 70 and 200 nm and length of the as-produced fiber is 50 – 200 µm. Nanofibers are much smaller in diameter when compared to conventional milled or continuous carbon fibers but definitely larger than carbon nanotubes, which lie between 1 and 10 nm.

Figure 1 shows that PR-19 has an average diameter of 150 nm, chemically vapor deposited carbon layer on the fiber surface over a catalytic layer as shown in Figure 1. Since the fibers are obtained in a vapor phase they get entwined during growth resulting in a mesh-like configuration. Debulking of this raw form is then done to offer the customer a uniform bulk density product enabling precise compounding into the final product. Pyrograf-III is presently offered in a debulked form termed as XT. This form has a bulk density of 1-3 lb/ft3.

Figure 1. Transmission electrom micrograph showing catalytic layer

PR-19-XT-PS Data Sheet

Product nomenclature

PR-19 has an average diameter of about 150 nm and has a chemically vapor deposited (CVD) layer of carbon on the fiber surface over a graphitic tubular core fiber. It is available in three grades designated as PS, LHT and HHT. The PS grade carbon nanofiber is obtained by pyrolytically stripping the as- produced fiber to remove polyaromatic hydrocarbons from the fiber surface.

Table 1. Carbon nanofiber properties

Fiber diameter, nm (average): 150
CVD carbon overcoat present on fiber: yes
Surface area, m2/gm: 20-30
Dispersive surface energy, mJ/m2: 120-140
Moisture, wt%: <5
Iron, ppm: <14,000
Polyaromatic hydrocarbons, mg PAH/gm fiber: <1

PR-19 XT-PS finds applications in mechanical, and electrical (for ESD applications)

PR-19-XT-LHT Data Sheet

Product Nomenclature

Heat treatment of the fiber at 1500°C helps obtain the LHT grade. By this, any chemically vapor deposited carbon present on the fiber surface is converted to a short-range ordered structure. There is an increase in the fiber’s inherent conductivity.

Table 2. Carbon nanofiber properties

Fiber diameter, nm (average): 150
CVD carbon overcoat present on fiber: no
Surface area, m2/gm: 20-30
Dispersive surface energy, mJ/m2: 120-140
Moisture, wt%: <5
Iron, ppm: <14,000
Polyaromatic hydrocarbons, mg PAH/gm fiber: <1

PR-19 XT-LHT finds applications in mechanical, and electrical fields.

PR-19-XT-HHT Data Sheet

Product Nomenclature

Heat-treatment of the as-produced carbon nanofiber to 3000°C produces the HHT grade. The fiber is thus converted to a fully graphitized form and creates a highly conductive carbon nanofiber. The iron content that is the catalyst is also reduced to very low levels.

Table 3. Carbon nanofiber properties

Fiber diameter, nm (average): 150
CVD carbon overcoat present on fiber: no
Surface area, m2/gm: 15-25
Dispersive surface energy, mJ/m2: 265-285
Moisture, wt%: <5
Iron, ppm: <100
Polyaromatic hydrocarbons, mg PAH/gm fiber: <1

PR-19 finds applications in Electrical, Thermal, and Electronic Devices.

About Pyrograf

Pyrograf Products, Inc. (PPI) is one of the leading producers of carbon nanofibers worldwide.

Pyrograf Products focuses on manufacturing high- quality, low-cost carbon nanofibers utilizing the proprietary and patented vapor grown carbon fiber (VGCF) process. Pyrograf-III, developed Applied Sciences, Inc. (ASI), is a versatile vapor grown carbon nanofiber with a wide range of applications.

This information has been sourced, reviewed and adapted from materials provided by Pyrograf.

For more information on this source, please visit Pyrograf.

Date Added: Aug 17, 2012 | Updated: Jun 11, 2013
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