169
6
properties, size, and shape are important for processability. A table
showing the processability of reinforcement and matrices vis-á-vis
to the processing methods was presented in . Table 5.2 of 7 Chap.
5. The selection criteria for the reinforcement of thermosetting
composites are dependent on the processability factors of reinforcement as well as the processing technology. The processability factors for reinforcement are detailed next.
6.7.1 Properties Driven Selection Criteria
5 Form of Reinforcement—In thermoplastic composites, all forms
and shapes of reinforcements, as described in earlier sections,
are used. Usage of reinforcement depends upon the moulding
process described in . Table 6.10.
5 Wettability of Reinforcement—The surface of reinforcement
must have a high surface energy in order to allow the resin to
wet it. The wettability of the reinforcement ensures a good
interphase between the reinforcement and the matrix. This will
result in a good composite.
5 Chemical Interaction with Resin—The hydrophobic surface of
reinforcement will allow the formation of a chemical bond
with an organic matrix. This will yield into a good interphase.
The reinforcement must be selected based on its capability of
having a good chemical interaction with matrix.
5 Fire Resistance—This is an important parameter from the point of
view of safety. Mostly synthetic reinforcing fibres are fire safe—
except for UHMWPE, PP, and PEEK. Natural fibres are susceptible to fire hazards, so care must be taken that the processing
temperature must be less than their ignition temperature.
. Table 6.10 Processability of reinforcement and thermoplastic
matrices vis-á-vis their processing methods
Serial
No.
Reinforcement
Processing
method
Matrices
1.
Synthetic fibres
(glass/carbon/
aramid)
All thermoplastic
matrices
(a) Short fibres/
staples/whiskers
Injection
moulding
(b) Long fibres
Compression
moulding
2.
Natural fibres
All thermoplastic
matrices (except
high-temperature
matrices, such as
PEEK, PEI, PES, PEK,
or PAI)
(a) Short fibres/
staples
Injection
moulding
(b) Long fibres
Compression
moulding
6.7 · Selection Criteria for Reinforcement
6
properties, size, and shape are important for processability. A table
showing the processability of reinforcement and matrices vis-á-vis
to the processing methods was presented in . Table 5.2 of 7 Chap.
5. The selection criteria for the reinforcement of thermosetting
composites are dependent on the processability factors of reinforcement as well as the processing technology. The processability factors for reinforcement are detailed next.
6.7.1 Properties Driven Selection Criteria
5 Form of Reinforcement—In thermoplastic composites, all forms
and shapes of reinforcements, as described in earlier sections,
are used. Usage of reinforcement depends upon the moulding
process described in . Table 6.10.
5 Wettability of Reinforcement—The surface of reinforcement
must have a high surface energy in order to allow the resin to
wet it. The wettability of the reinforcement ensures a good
interphase between the reinforcement and the matrix. This will
result in a good composite.
5 Chemical Interaction with Resin—The hydrophobic surface of
reinforcement will allow the formation of a chemical bond
with an organic matrix. This will yield into a good interphase.
The reinforcement must be selected based on its capability of
having a good chemical interaction with matrix.
5 Fire Resistance—This is an important parameter from the point of
view of safety. Mostly synthetic reinforcing fibres are fire safe—
except for UHMWPE, PP, and PEEK. Natural fibres are susceptible to fire hazards, so care must be taken that the processing
temperature must be less than their ignition temperature.
. Table 6.10 Processability of reinforcement and thermoplastic
matrices vis-á-vis their processing methods
Serial
No.
Reinforcement
Processing
method
Matrices
1.
Synthetic fibres
(glass/carbon/
aramid)
All thermoplastic
matrices
(a) Short fibres/
staples/whiskers
Injection
moulding
(b) Long fibres
Compression
moulding
2.
Natural fibres
All thermoplastic
matrices (except
high-temperature
matrices, such as
PEEK, PEI, PES, PEK,
or PAI)
(a) Short fibres/
staples
Injection
moulding
(b) Long fibres
Compression
moulding
6.7 · Selection Criteria for Reinforcement