Civil Engineering Reference
In-Depth Information
the N
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atmosphere. h e single cantilever mode at a frequency of 1 Hz was used with a
dynamic mechanical analyzer (DMA Q 800, TA Instruments). h e instrument was cali-
brated to have the correct clamp position and compliance before each measurement.
h e specimen dimension was 3.5 mm × 1.2 mm × 1.7 mm.
7.2.3.4
Tensile Properties
h e tensile properties of the nanobiocomposites were measured at room tempera-
ture using a Universal Testing Machine (UTM, Tinius Olsen Ltd., H50K-S T, Redhill,
England) according to ASTM D 638 standard with a gauge length of 5 mm. h e speci-
mens were molded in a size of 3.18 mm × 63.66 mm × 3.00 mm with a crosshead speed
of 10 mm/min. Each value obtained represented the average of i ve samples.
7.2.3.5
Flexural Properties
h e l exural properties of the nanobiocomposites were measured at room tempera-
ture using a Universal Testing Machine (UTM, Tinius Olsen Ltd., H50K-S T, Redhill,
England) according to ASTM D 790M test method I. h e specimens were tested in
three-point bending with a crosshead speed of 1 mm/min and loading span-to-depth
ratio at 16. h e specimen dimension was 50 mm × 25 mm × 2 mm. Each value obtained
represented the average of i ve samples.
7.2.3.6
Impact Properties
Izod impact strength of notched and unnotched samples was carried out using a
Pendulum Impact Tester (Tinius Olsen, Model - IT 504, Redhill, England) instrument
according to ASTM D 256 standard. h e specimens were notched by an automatic
specimen notcher (Model-899, Tinius Olsen Ltd., Redhill, UK). h e specimen dimen-
sion was 12.5 mm × 63.5 mm × 5.0 mm. h e measurements were performed at ambient
conditions, and samples were tested in replicates of i ve each. h e impact energy was
divided by the width of the specimens to yield impact strength (J/m).
7.2.3.7
Surface Morphology (SEM & EDX)
h e surface morphologies of fractured surfaces of nanobiocomposites were observed
with scanning electron microscope (SEM, S-4800, Hitachi, Japan) and energy disper-
sive X-ray (EDX). h e fractured surface of biocomposites was prepared with impact
test specimens. Prior to the observation, all the specimens were coated with Au in order
to prevent electrical discharge. h e acceleration voltage used was 15-25 kV.
7.3
Results and Discussion
7.3.1
h
ermal Properties (TGA)
Figure 7.1 shows the thermogravimetric (DTG) curves as thermal stability of PP matrix,
PP/KE biocomposites and PP/KE/nanoclay nanobiocomposites. As shown in Figure 7.1,
the PP matrix shows the single maximum decomposition peak at 449.6°C, and the PP/
