Environmentally Degradation of r-PMMA/PMMA-Blend-PU/Ecoflex ...

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Environmentally Degradation of r-PMMA/PMMA-Blend-PU/Ecoflex Sheet
where :
W a is weight of sample after extraction;
W b is weight of sample before extraction.
2.3.2 Mechanical Tests
The impact strength both Izod and Charpy types
were determined according to ASTM D256 [9] and
ASTM D6110 [10] respectively. The specimens were
tested by using impact strength machine and the energy
of hammer was 7.5 J (Impact tester: Italy Cast Type
695700).
2.3.3 The Ultraviolet Degradation
The ultraviolet degradation was examined according
to QUV-A cabinet from PAN ASIA Industry Co., Ltd.
Thailand standard by detecting the total change in color
from Gretag Macbeth Model COLOR iMATCH,
before and after located in QUV test for 14 days
(according to PAN Asia Industrial Co. Ltd., the 7 days
in QUV-A cabinet was equal to one year). After
ultraviolet degradation r-PMMA/PMMA-blend-PU/
Ecoflex sheet was determined the impact strength to
compare the r-PMMA/PMMA-blend-PU/Ecoflex sheet
before testing.
2.3.4 Degradation of r-PMMA/PMMA-Blend-PU/
Ecoflex Sheet by Landfills
The specimens of r-PMMA/PMMA-blend-PU/
Ecoflex sheet were taken landfills for six months. The
specimens were buried in covered soil under naturally
condition for biodegradability. After the expiry of the
time, the specimens used methods for monitoring in
vitro such as the percentage of weight loss and the
surface morphology of SEM micrographs. The results
are discussed in more detail below.
2.3.5 Surface Morphology of r-PMMA/PMMA-
Blend-PU/Ecoflex Sheet
A JEOL JSM-5410LV scanning electron
microscope was used to examine the surface
morphology of r-PMMA/PMMA-blend-PU/Ecoflex
sheet. The specimens were prepared by fracture in
cryogenically in liquid nitrogen.
3. Results and Discussion
3.1 Mechanical Properties of r-PMMA/PMMA-Blend-
PU/Ecoflex Sheet
The impact strength property of the
r-PMMA/PMMA-blend-PU/Ecoflex sheet were
modified poly (methyl methacrylate) sheet with
polyurethane by using IPNs technique (by Izod and
Charpy type) are shown in Table 1. It shows that the
highest impact was observed at MMA:r-PMMA:PU
(72:3:25)/3 EF and (71:4:25)/3 EF, but the impact
strength of MMA:r-PMMA:PU (71:4:25)/3 EF is
higher than MMA:r-PMMA:PU (72:3:25)/3 EF. This is
probably due to structure of EF was ester bond that was
interacted with -NHCOO group on PMMA/PU
polymer networks. This behavior was led EF particle
embedded between polymer networks of PMMA/PU
[4]. However, the comparing impact strength of
r-PMMA/PMMA-blend-PU/Ecoflex sheet without EF
was slightly more than r-PMMA/PMMA-blend-PU/
Ecoflex sheet with EF. It can be concluded that
r-PMMA did not affect impact strength of PMMA.
Hence, r-PMMA has been possible to recycle into
production process, by dissolves within MMA.
3.2 Surface Morphology and Percentage of IPNs of
Impact Modified PMMA Sheet
The percentage of IPNs that were estimated by
solvent extraction to determine grafted MMA
monomer and uncross-linking PMMA in the final
product are shown in Table 1, shown
MMA:r-PMMA:PU (71:4:25)/3 EF was the highest
percentage of IPNs when compared with other amount
of EF monomer in casting process.
The results of surface morphology by SEM
(scanning electron microscope) of r-PMMA/PMMAblend-PU/Ecoflex
sheet were shown in Fig. 2.
The r-PMMA/PMMA-blend-PU/Ecoflex sheet
consists of the previously polymer from r-PMMA