Various methods of toughening the bonding between the interleaf and laminate glass fiber reinforced polymer (GFRP) have been developed due to the increasing applications in industries. A polystyrene (PS) additive modified epoxy is used to improve the diffusion and precipitation region between polysulfone (PSU) interleaf and epoxy due to its influence on the curing kinetics without changing glass transition temperature and viscosity of the curing epoxy. The temperature-dependent diffusivities of epoxy, amine hardener, and PSU are determined by using attenuated total reflection–Fourier transfer infrared spectroscopy (ATR–FTIR) through monitoring the changing absorbance of their characteristic peaks. Effects of PS additive on diffusivity in the epoxy system are investigated by comparing the diffusivity between nonmodified and PS modified epoxy. The consumption rate of the epoxide group in the curing epoxy reveals the curing reaction rate, and the influence of PS additive on the curing kinetics is also studied by determining the degree of curing with time. A diffusivity model coupled with curing kinetics is applied to simulate the diffusion and precipitation process between PSU and curing epoxy. The effect of geometry factor is considered to simulate the diffusion and precipitation process with and without the existence of fibers. The simulation results show the diffusion and precipitation depths which match those observed in the experiments.

References

References
1.
Shetty
,
R. R.
,
Pavithra
,
G. K.
, and
Rai
,
S. K.
,
2013
, “
Studies on Mechanical and Fractographic Behavior of Polycarbonate-Toughened Epoxy-Granite Particle Hybrid Composites
,”
Polym.-Plast. Technol. Eng.
,
52
(
11
), pp.
1122
1126
.
2.
Pena
,
G.
,
Eceiza
,
A.
,
Valea
,
A.
,
Remiro
,
P.
,
Oyanguren
,
P.
, and
Mondragon
,
I.
,
2003
, “
Control of Morphologies and Mechanical Properties of Thermoplastic-Modified Epoxy Matrices by Addition of a Second Thermoplastic
,”
Polym. Int.
,
52
(
9
), pp.
1444
1453
.
3.
Xu
,
Y.
,
Liao
,
G.
,
Gu
,
T.
,
Zheng
,
L.
, and
Jian
,
X.
,
2008
, “
Mechanical and Morphological Properties of Epoxy Resins Modified by Poly(Phthalazinone Ether Sulfone Ketone)
,”
J. Appl. Polym. Sci.
,
110
(
4
), pp.
2253
2260
.
4.
Martines
,
I.
,
Martin
,
M. D.
,
Eceiza
,
A.
,
Oyanguren
,
P.
, and
Mondragon
,
I.
,
2000
, “
Phase Separation in Polysolfune-Modified Epoxy Mixtures. Relationships Between Curing Conditions, Morphology and Ultimate Behavior
,”
Polymer
,
41
(
3
), pp.
1027
1035
.
5.
Blanco
,
I.
,
Cicala
,
G.
, and
Faro
,
C. L.
,
2003
, “
Improvement of Thermomechanical Properties of a DGEBS/DDS System Blended With a Novel Thermoplastic Copolymer by Realization of a Semi-IPN Network
,”
J. Appl. Polym. Sci.
,
88
(
13
), pp.
3021
3025
.
6.
Heitzmann
,
M. T.
,
Hou
,
M.
,
Verdt
,
M.
,
Vandi
,
L.
, and
Paton
,
R.
,
2011
, “
Morphology of an Interface Between Polyetherimide and Epoxy Prepreg
,”
Adv. Mater. Res.
,
393–395
, pp. 184–188.
7.
Milliman
,
H. W.
,
Boris
,
D.
, and
Schiraldi
,
D. A.
,
2012
, “
Experimental Determination of Hansen Solubility Parameters for Select POSS and Polymer Compounds as a Guide to POSS—Polymer Interaction Potentials
,”
Macromolecules
,
45
(
4
), pp.
1931
1936
.
8.
Yun
,
N. G.
,
Won
,
Y. G.
, and
Kim
,
S. C.
,
2004
, “
Toughening of Epoxy Composite by Dispersing Polysulfone Particle to Form Morphology Spectrum
,”
Polym. Bull.
,
52
(
5
), pp.
365
372
.
9.
Vandi
,
L. J.
,
Hou
,
M.
,
Veidt
,
M.
,
Truss
,
R.
,
Heitzmann
,
M.
, and
Paton
,
R.
,
2012
, “
Interface Diffusion and Morphology of Aerospace Grade Epoxy Co-Cured With Thermoplastic Polymers
,”
28th International Congress of the Aeronautical Sciences
(
ICAS
), Brisbane, Australia, Sept. 23–28.
10.
Bulter
,
C. A.
,
McCullough
,
R. L.
,
Pitchumani
,
R.
, and
Gillespie
,
J. W.
,
1998
, “
An Analysis of Mechanisms Governing Fusion Bonding of Thermoplastic Composites
,”
J. Thermoplast. Compos. Mater.
,
11
, pp.
338
363
.
11.
Sorrentino
,
A.
,
Gorrasi
,
G.
,
Tortora
,
M.
, and
Vittoria
,
V.
,
2006
, “
Barrier Properties of Polymer/Clay Nanocomposites
,”
Polym. Nanocompos.
,
11
, pp.
273
292
.
12.
Bian
,
D.
,
Beeksma
,
B. R.
,
Shim
,
D. J.
,
Jones
,
M.
, and
Yao
,
Y. L.
, “
Interlaminar Toughening of GFRP, Part 1: Improved Diffusion and Precipitation
” (unpublished)
.
13.
Sanford
,
W. M.
,
1987
, “
Curing Behavior of Thermosetting Resin Composites
,” Ph.D. thesis, University of Delaware, Newark, DE.
14.
Skourlis
,
T. P.
, and
McCullough
,
R. L.
,
1994
, “
Measurement of Diffusivity of a Liquid Diamine in Solid Epoxies Using Attenuated Total Reflectance Infrared Spectroscopy
,”
J. Appl. Polym. Sci.
,
52
(
9
), pp.
1241
1248
.
15.
Rajagopalan
,
G.
,
Immordino
,
K. M.
,
Gillespie
,
J. W.
, and
McKnight
,
S. H.
,
2000
, “
Diffusion and Reaction of Epoxy and Amine in Polysulfone Studied Using Fourier Transfer Infrared Spectroscopy: Experimental Results
,”
Polymer
,
41
(
7
), pp.
2591
2602
.
16.
Hardis
,
R.
,
2012
, “
Cure Kinetics Characterization and Monitoring of an Epoxy Resin for Thick Composite Structures
,”
M.Sc. thesis
, Iowa State University, Ames, IA.
17.
Dibenedetto
,
A. T.
,
1987
, “
Prediction of the Glass Transition Temperature of Polymers: A Model Based on the Principle of Corresponding States
,”
J. Polym. Sci.
,
25
(
9
), pp.
1949
1969
.
18.
Rajagopalan
,
G.
,
Gillespie
,
J. W.
, and
McKnight
,
S. H.
,
2000
, “
Diffusion of Reacting Epoxy and Amine Monomers in Polysulfone: A Diffusivity Model
,”
Polymer
,
41
(
21
), pp.
7723
7733
.
19.
Rajagopalan
,
G.
,
Narayanan
,
C.
,
Gillespie
,
J. W.
, and
Mcknight
,
S. H.
,
2000
, “
Diffusion and Reaction of Epoxy and Amine in Polysulfone—Transport Modeling and Experimental Validation
,”
Polymer
,
41
, pp.
8532
8556
.
20.
Mangaraj
,
D.
,
Bhatnagar
,
S. K.
, and
Rath
,
S. B.
,
1963
, “
Cohesive-Energy-Density of High Polymers. Part III: Estimation of C.E.D by Viscosity Measurement
,”
Macromol. Chem. Phys.
,
67
(
1
), pp.
75
83
.
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