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Title: Effect of interfacial chemical bonding and surface topography on adhesion in carbon fiber/epoxy composites

Abstract

A series of PAN-based IM6 carbon fibers having varying amounts of surface treatment were, pretreated with compounds representing the constituents encountered in epoxy composites to pre-react any groups on the fiber surface before composite fabrication in order to determine the effect of chemical bonding on fiber-matrix adhesion. Chemical bonding was quantified using XPS. Chemical bonding between reactive groups in amine cured epoxy matrices and the surface groups present on IN46 carbon fibers as a result of commercial surface treatments has been detected although the absolute amount of chemical bonding is low (1-3%). It was found that reaction with monofunctional epoxy groups having hydrocarbon functionalities blocked the surface from further reaction and reduced the adhesion that could be attained to its lowest value. Prereaction with difunctional amines had little effect on adhesion when compared to normal composite fabrication procedures. Prereaction with difunctional epoxy groups did enhance adhesion levels over the level attained in normal composite fabrication methods. These results showed that chemical bonding between epoxy and the carbon fiber surface could increases the adhesion between fiber and matrix about 25% while between the amino group and the carbon fiber surface about 15%. Quantitative measurements of the fiber surface microtopography were mademore » with scanning tunneling microscopy. An increase in roughness was detected with increasing surface treatment. It was concluded that surface roughness also accounted for a significant increase in fiber-matrix adhesion.« less

Authors:
; ;  [1]
  1. Michigan State Univ., East Lansing, MI (United States). Composite Materials and Structures Center|[Mitsubishi Rayon Co., Nagoya (Japan)
Publication Date:
OSTI Identifier:
89882
Report Number(s):
CONF-9409291-
ISBN 1-56676-220-0; TRN: IM9536%%312
Resource Type:
Conference
Resource Relation:
Conference: 9. technical conference of the American Society for Composites, Newark, DE (United States), 20-22 Sep 1994; Other Information: PBD: 1994; Related Information: Is Part Of Proceedings of the American Society for Composites: Ninth technical conference; PB: 1319 p.
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; COMPOSITE MATERIALS; INTERFACES; FABRICATION; CARBON FIBERS; ROUGHNESS; ADHESION; EPOXIDES; CHEMICAL BONDS; SAMPLE PREPARATION; CHEMICAL REACTIONS; OXYGEN; NITROGEN; MICROSCOPY; SURFACE TREATMENTS

Citation Formats

Drzal, L.T., Sugiura, N., and Hook, D. Effect of interfacial chemical bonding and surface topography on adhesion in carbon fiber/epoxy composites. United States: N. p., 1994. Web.
Drzal, L.T., Sugiura, N., & Hook, D. Effect of interfacial chemical bonding and surface topography on adhesion in carbon fiber/epoxy composites. United States.
Drzal, L.T., Sugiura, N., and Hook, D. 1994. "Effect of interfacial chemical bonding and surface topography on adhesion in carbon fiber/epoxy composites". United States. doi:.
@article{osti_89882,
title = {Effect of interfacial chemical bonding and surface topography on adhesion in carbon fiber/epoxy composites},
author = {Drzal, L.T. and Sugiura, N. and Hook, D.},
abstractNote = {A series of PAN-based IM6 carbon fibers having varying amounts of surface treatment were, pretreated with compounds representing the constituents encountered in epoxy composites to pre-react any groups on the fiber surface before composite fabrication in order to determine the effect of chemical bonding on fiber-matrix adhesion. Chemical bonding was quantified using XPS. Chemical bonding between reactive groups in amine cured epoxy matrices and the surface groups present on IN46 carbon fibers as a result of commercial surface treatments has been detected although the absolute amount of chemical bonding is low (1-3%). It was found that reaction with monofunctional epoxy groups having hydrocarbon functionalities blocked the surface from further reaction and reduced the adhesion that could be attained to its lowest value. Prereaction with difunctional amines had little effect on adhesion when compared to normal composite fabrication procedures. Prereaction with difunctional epoxy groups did enhance adhesion levels over the level attained in normal composite fabrication methods. These results showed that chemical bonding between epoxy and the carbon fiber surface could increases the adhesion between fiber and matrix about 25% while between the amino group and the carbon fiber surface about 15%. Quantitative measurements of the fiber surface microtopography were made with scanning tunneling microscopy. An increase in roughness was detected with increasing surface treatment. It was concluded that surface roughness also accounted for a significant increase in fiber-matrix adhesion.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 1994,
month =
}

Conference:
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