Page 61 - Polymer-based Nanocomposites for Energy and Environmental Applications

Preparation and properties of nanopolymer advanced composites: A review 39

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40
Short beam shear strength (MPa) 30
35

25
20

15
10

5
0
0.1% SWNTs
No SWNTs (control) No SWNTs 0.2% SWNTs 0.1% F-SWNTs 0.1% Ally-SWNTs
0.1% Bn SWNTs
0.1% Silane-SWNTs
Formulation of nanotubes
Fig. 2.12 Short-beam shear strength comparison of composites with nanotubes [27].

are shown in Fig. 2.12. The interlaminar shear strengths of glass fabric/vinyl ester
composites treated with various SWNTs are significantly improved with respect to
that of the composite control samples.
Woven glass fiber-reinforced laminates using CNT/PA6 nanocomposite as the
matrix were manufactured with glass fiber volume fraction of 30 2 vol% through
film stacking and fiber impregnation in a hot press by Shen et al. [28]. A suitable
processing ability of CNT/PA6 nanocomposites has been achieved by choosing a
commercial CNT/PA6 nanocomposite (20% CNT in low viscosity PA6) diluted with
an extrusion grade PA6, that is found to provide the suitable processing characteristics
for extrusion of uniform and defect free PA6 nanocomposite films containing up to
4 wt% of CNT. These films were subsequently used in the laminate fabrication. Flex-
ural modulus and strength of the laminate, contain as low as 0.5 or 1 wt% CNT in PA6
and they have been shown to improve by over 17% and 32%, respectively. HDT of the
laminates are not affected by incorporation up to 4 wt% CNT in PA6, while the ther-
mal stability of CNT/PA6 nanocomposites is increased with CNT loadings. The ther-
mal conductivity of the laminate samples increased is by 42% with 2 wt% CNT. The
thermal conductivities of the different CNT/PA6 nanocomposites and the
corresponding laminates are summarized in Table 2.5.
Also, this study demonstrates the feasibility of producing advanced thermoplastic
laminates with enhanced thermal stability, thermal conductivity, mechanical proper-
ties, and delayed ignition time and peak HRR time by incorporating a small amount
CNT (up to 2 wt%).