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

Journal of Environmental Science and Engineering A 1 (2012) 1036-1042
Formerly part of Journal of Environmental Science and Engineering, ISSN 1934-8932
D
DAVID
PUBLISHING
Environmentally Degradation of
r-PMMA/PMMA-Blend-PU/Ecoflex Sheet
Narumol Kreua-ongarjnukool, Kwankao Karnpakdee and Pensiri Rattanasupa
Department of Industrial Chemistry, Faculty of Applied Science, King Mongkut’s University of Technology North Bangkok, Bangkok
10800, Thailand
Received: July 30, 2012 / Accepted: August 15, 2012 / Published: August 20, 2012.
Abstract: Poly (methyl methacrylate) scrap was applied to prepare the impact modification of r-PMMA/PMMA-blend-PU/Ecoflex
sheet by casting process. The Ecoflex and polyurethane were used as biodegradable polymer and impact modified respectively. This
research was ascertained the way to reduce the processing cost of PMMA sheet and the industrial waste by recycled PMMA scrap into
the production process. The r-PMMA/PMMA-blend-PU/Ecoflex sheet was studied potential degradation by landfills for six months.
After degradation the percentage of weight loss of specimens was increasing depend on amount of Ecoflex content and degradation
period. While, the surface morphology of r-PMMA/PMMA-blend-PU/Ecoflex sheet after six months was damaged and demonstrated
that Ecoflex had an effect on PMMA-blend-PU sheet in potential biodegradation. The mechanical and physical properties of
r-PMMA/PMMA-blend-PU/Ecoflex sheet were described. Finally, the impact strength of r-PMMA/PMMA-blend-PU/Ecoflex sheet
from this research, it is possible to use r-PMMA and Ecoflex in the acrylic casting sheet product.
Key words: Ecoflex, casting process, PMMA/PU, IPNs (interpenetrating polymer networks), PMMA scrap.
1. Introduction
Presently, acrylic sheet was the trade name of poly
(methyl methacrylate) (PMMA) which was prepared
by bulk polymerization of MMA (methyl methacrylate
monomer) via casting process [1, 2]. PMMA are
utilized in almost every manufacturing. Owing to
qualification of hardness, transparent and high of heat
resistance poly (methyl methacrylate) is widely used
in many application fields, such as automobile parts,
lenses, transparency roofs, etc.. Whereas, poly (methyl
methacrylate) had inferior as brittleness and scratch.
PU (Polyurethane) was used in this research to
modified impact properties of poly (methyl
methacrylate) as mention earlier [1, 3]. The thermoset
of polyurethane was prepared from synthesis reaction
of diisocyanate and diol or triol, or polyol. Reasoning
Corresponding author: Narumol Kreua-ongarjnukool,
associate professor, main research fields: impact modification of
PMMA, mechanical characteristics of filled polymers and
blends, electrostatic spinning of polymers and applications.
E-mail: nkk@kmutnb.ac.th.
the advantage properties of polyurethane are
toughness on surface and high strength.
The advantage of polyurethane were improved the
impact and solved the brittle properties of the
poly(methyl methacrylate) by IPNs (interpenetrating
polymer networks) technique [4]. Moreover, in the
line PMMA sheet processing production observed the
garbage from cutting process, called PMMA scrap
(r-PMMA). The r-PMMA scrap in production plant
occurs about one ton per year. Therefore, PMMA
scrap was studied to recycle in this research by mixed
with methyl methacrylate monomer to decrease plastic
garbage in industry.
Furthermore, in this research was appreciated to the
problem on environment due to plastics are difficult to
degradation. The result of remarkable increasing
demand for environmentally friendly materials has
drawn most research attentions toward biodegradable
materials. Thus, the poly (butylenes adipate-coterephthalate),
trade name of EF (Ecoflex), was used in

Environmentally Degradation of r-PMMA/PMMA-Blend-PU/Ecoflex Sheet 1037
this research as a biodegradable polymer. The
molecular structure of EF is shown in Fig. 1. Also the
interesting property of EF is able biodegradable in
environment [5]. Moreover, structure of EF might be
contributed to increase the impact property of poly
(methyl methacrylate).
The objective of this research was to prepare
r-PMMA/PMMA-blend-PU/Ecoflex sheet by bulk
polymerization via casting process. The mechanical
and physical properties of r-PMMA/PMMAblend-PU/Ecoflex
sheet were also investigated. Finally,
r-PMMA/PMMA-blend-PU/Ecoflex sheet was studied
an effect of biodegradable polymer, EF on potential
biodegradation to r-PMMA/PMMA- blend-PU sheet,
which can use for industry.
2. Experiment
2.1 Materials
Methyl methacrylate monomer (MMA monomer),
linear glycol adipate polyester polyol (T2000),
Aliphatic hexamethylene diisocyanate, Azo-bis-2,4-
dimethyl valeronitrile, EGDM (ethylene glycol
dimethacrylate) and dibutyl tin laurate (DBTL) were
supplied by PAN ASIA Industry Co., Ltd., Chloroform
and petroleum ether were purchased from Labscan
Asia Co., Ltd and Fisher Scientific respectively.
Ecoflex F BX 7011: (BASF Co., Ltd) was obtained
from National MTEC (Metal and Materials
Technology Center). All of these chemicals were used
without further purification.
2.2 Preparation of r-PMMA/PMMA-Blend-PU/Ecoflex
Sheet
The radical bulk polymerization of
r-PMMA/PMMA-blend-PU/Ecoflex sheet was
prepared from r-PMMA dissolved in MMA monomer.
The ratio of MMA:r-PMMA:PU was used to prepared
r-PMMA/PMMA-blend-PU/Ecoflex sheet were
72:3:25 and 71:4:25 [6] under viscous agitation. The
EF was dissolved in chloroform and added to MMA
monomer, variable amount of EF 1, 2, 3, 4 and 5 phr.
The reaction was carried out at room temperature with
continuous stirring. After stirring, the polymerization
of polyurethane was started by agitation of mixture the
diisocyanate and polyol. After that MMA solution was
added into the polyurethane prepolymer. The mixture
was stirred to get well homogenous solution at room
temperature for 30 minutes. The solution was degassed
using a vacuum pump, and then poured into
polymerization casting mould and left into water bath
at 60 o C for 3 hour. Finally, the polymerization casting
cells were placed in the oven at 100 o C for 2 hours in
order to complete free radical polymerization. The
r-PMMA/PMMA-blend-PU/Ecoflex sheet was taken
from the glass-mold after cooling at room temperature.
2.3 Characterization of r-PMMA/PMMA-Blend- PU/
Ecoflex Sheet
2.3.1 IPNs (Interpenetrating Polymer Networks)
Determination
In order to estimate the amount of unreacted starting
material which was grafted MMA monomer and
uncross-linked PMMA in the final product. The
efficiency of cross-linking reactions, a known weight
of the product was extracted by soxhlet extraction with
dichloromethane for a period of 72 hours. After
extraction, the sample was dried in a vacuum oven. The
percentage of IPNs (%IPNs) [7, 8] was calculated in Eq.
(1):
W (%) IPNs = 100 -
a
W
b
W b
× 100 (1)
Fig. 1 Chemical structure of poly (butylenes adipate-co-terephthalate), EF (Ecoflex).

1038
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

Environmentally Degradation of r-PMMA/PMMA-Blend-PU/Ecoflex Sheet 1039
Table 1 Percentage of IPNs and impact strength of r-PMMA/PMMA-blend-PU/Ecoflex.
MMA:r-PMMA:PU
(%wt)
72:3:25
71:4:25
Amount of ecoflex
Impact strength (kJ/m 2 )
%IPNs
(phr)
Izod
Charpy
GP - 8.16 ± 0.14 13.96 ± 0.21
0 98.50 ± 0.46 23.39 ± 0.41 29.31 ± 1.32
1.0 96.43 ± 0.38 13.26 ± 0.77 17.58 ± 0.09
2.0 96.97 ± 0.10 12.05 ± 0.07 15.40 ± 0.61
3.0 97.39 ± 0.28 15.16 ± 1.68 21.87 ± 0.45
4.0 96.08 ± 0.46 13.57 ± 0.16 17.60 ± 1.83
5.0 94.75 ± 0.12 11.96 ± 1.12 16.13 ± 1.64
0 99.21 ± 0.05 19.51 ± 0.73 24.11 ± 0.57
1.0 96.96 ± 0.66 16.25 ± 1.38 21.07 ± 1.90
2.0 96.98 ± 0.89 14.47 ± 0.14 18.10 ± 0.09
3.0 98.25 ± 0.24 17.06 ± 1.74 23.80 ± 1.34
4.0 97.33 ± 1.80 14.78 ± 0.11 18.12 ± 0.44
5.0 95.98 ± 0.80 14.75 ± 0.29 19.58 ± 1.18
GP = general purpose of PMMA from PAN ASIA Industry Co., Ltd..
(a)
(b)
(c)
(d)
Fig. 2 SEM micrographs of r-PMMA/PMMA-blend-PU/Ecoflex sheet (× 1,000: scale bar = 10 m). (a) 3%
r-PMMA/PMMA-blend-PU; (b) 3% r-PMMA/PMMA-blend-PU + EF 3 phr; (c) 4% r-PMMA/PMMA-blend-PU; (d) 4%
r-PMMA/PMMA-blend-PU + EF 3 phr.
distributed in the PMMA matrix correspond to
compatibility of MMA, PU and EF.
3.3 The Ultraviolet Degradation
The ultraviolet degradation of r-PMMA/PMMAblend-PU/Ecoflex
sheet was examined by monitoring
the change of impact strengths. The results are shown
in Table 2. The impact strength of specimens were
slightly decreased due to the ultraviolet was activated
PMMA to form methyl methacrylate free radical.
However, the impact strength of r-PMMA/
PMMA-blend-PU/Ecoflex sheet were less changed
both of Izod and Charpy type. These results
demonstrated
that

1040
Environmentally Degradation of r-PMMA/PMMA-Blend-PU/Ecoflex Sheet
r-PMMA/PMMA-blend-PU/Ecoflex sheet can be
usable in authentic environment over two years.
3.4 Degradation of r-PMMA/PMMA-Blend-PU/
Ecoflex Sheet by Landfills
In Table 3, the potential biodegradation of the
r-PMMA/PMMA-blend-PU/Ecoflex sheet was shown
in term of percentage of weight loss. After degradation
for six months, the percentage of weight loss of
specimens were increasing depend on amount of EF
content and degradation period.
Considerably to the chemical structure of EF was an
ester group that has effect with humidity during
embedded in soil [5]. The microbial organisms
digested carbon structure of EF on ester bond position,
then used carbon residues to produce their food source.
Consequently, humidity and microbial organisms
played crucial roles to render degradability of EF. Also,
they could be drived the potential degradation of
r-PMMA/PMMA-blend-PU/Ecoflex sheet as well.
Scanning electron micrographs on the surface
morphologies of damaged specimens were indicated in
Fig. 3.
According to Figs. 3(b5), 3(d5) shown the cracking
Table 2 The results form ultraviolet resistance in term of impact strength.
MMA:r-PMMA:PU
72:3:25
71:4:25
Amount of ecoflex
(phr)
Izod type
Impact strength (kJ/m 2 )
Charpy type
Before UV After UV (14 days) Before UV After UV (14 days)
0 23.39 ± 0.41 23.15 ± 0.88 29.31 ± 1.32 28.99 ± 0.43
1 13.26 ± 0.77 13.20 ± 0.09 17.58 ± 0.09 17.37 ± 0.10
2 12.05 ± 0.07 12.07 ± 0.15 15.40 ± 0.61 15.29 ± 1.51
3 15.16 ± 1.68 15.11 ± 0.52 21.87 ± 0.45 21.70 ± 0.64
4 13.57 ± 0.16 13.13 ± 0.83 17.60 ± 1.83 17.20 ± 0.56
5 11.96 ± 1.12 11.87 ± 0.36 16.13 ± 1.64 16.07 ± 0.23
0 19.51 ± 0.73 19.44 ± 0.25 24.11 ± 0.57 24.03 ± 0.20
1 16.25 ± 1.38 16.10 ± 0.21 21.07 ± 1.90 20.99 ± 0.21
2 14.47 ± 0.14 14.39 ± 0.90 18.10 ± 0.09 18.03 ± 0.28
3 17.06 ± 1.74 16.97 ± 1.01 23.80 ± 1.34 23.54 ± 1.03
4 14.78 ± 0.11 14.39 ± 0.01 18.12 ± 0.44 18.02 ± 0.34
5 14.75 ± 0.29 14.26 ± 0.63 19.58 ± 1.18 19.04 ± 0.37
Table 3 The percentage of weight loss of specimens after degradation in the period of six months.
PMMA:r-PMMA:PU
72:3:25
71:4:25
Amount of ecoflex (phr)
Percentage of weight loss after biodegradation by landfills method
1 M 6 M
0 0.6800 ± 0.11 5.9000 ± 1.01
1 0.8900 ± 0.16 9.3400 ± 0.11
2 1.2400 ± 0.26 10.5400 ± 0.23
3 3.1200 ± 0.13 12.4300 ± 0.33
4 4.1200 ± 1.30 11.9600 ± 0.98
5 5.1234 ± 0.46 12.9566 ± 0.45
0 0.4912 ± 0.12 5.1001 ± 1.28
1 0.9840 ± 0.43 6.3425 ± 0.21
2 1.2542 ± 0.15 8.3241 ± 0.98
3 2.1287 ± 0.76 10.9909 ± 0.88
4 3.0091 ± 0.67 11.8997 ± 0.46
5 4.1689 ± 0.43 12.1980 ± 0.55

Environmentally Degradation of r-PMMA/PMMA-Blend-PU/Ecoflex Sheet 1041
(a)
(c)
(b3)
(d3)
(b5)
(d5)
Fig. 3 SEM micrographs of r-PMMA/PMMA-blend-PU/Ecoflex sheet (× 1,000: scale bar = 10 m), tested before and after
degradation in the period of six months; (a) Before degradation 3% r-PMMA/PMMA-blend-PU; (b3) after degradation 3%
r-PMMA/PMMA-blend-PU + EF 3 phr; (b5) after degradation 3% r-PMMA/PMMA-blend-PU + EF 5 phr; (c) before
degradation 4% r-PMMA/PMMA-blend-PU; (d3) after degradation 4% r-PMMA/PMMA-blend-PU + EF 3 phr; (d5) after
degradation 4% r-PMMA/PMMA-blend-PU + EF 5 phr.
appeared on the fracture surface of r-PMMA/
PMMA-blend-PU/Ecoflex sheet. EF lead feature of
specimens to crevice indicate the specimens were
damaged [11].
These ester cleavage behavior significant affect on
decreased of weight loss depend on degradation period
[12, 13].
In addition to humidity, the EF was conducted
specimens to absorbed humidity in soil that influence
specimens swelled. Considering the results of surface
morphology by scanning electron microscope of
r-PMMA/PMMA-blend-PU/Ecoflex sheet shown that
surface morphology of specimens were damaged.
4. Conclusions
The impact modification of poly(methyl
methacrylate) sheet with polyurethane by using IPNs
technique and mixed r-PMMA and Ecoflex to recycled
plastic garbage and accrued potential of biodegradation
respectively. The results was shown that the highest

1042
Environmentally Degradation of r-PMMA/PMMA-Blend-PU/Ecoflex Sheet
mechanical properties was observed at ratio of
MMA:r-PMMA:PU (71:4:25)/3 EF. According to the
percentage of IPNs, it showed the maximum value in
this condition. When considered the results as potential
of biodegradation, it showed that r-PMMA/
PMMA-blend-PU/Ecoflex sheet from this research
could be degraded in soil by landfills method. Towards,
after landfills for 6 months, percentages of weight loss
were increased upon to amount of Ecoflex. In addition
to this, the SEMs image shown the surface morphology
of specimens were damaged. That illustrated Ecoflex
had an effect on r-PMMA/PMMA-blend-PU/Ecoflex
sheet in potential biodegradation due to swelled by
humidity and microbial enzymatic activity in soil.
However, the impact strength of
r-PMMA/PMMA-blend-PU/Ecoflex sheet from this
research was better than the GPPMMA from industry.
Hence, the r-PMMA/PMMA-blend-PU/Ecoflex sheet
can be utilized as the impact materials for variable
application with potential in biodegradation and
r-PMMA can reduce the costs of raw material in
PMMA casting process.
Acknowledgments
The authors acknowledge with thanks for financial
support from the iTAP (Industrial Technology
Assistance Program), NSTDA (National Science and
Technology Development Agency). Special thanks to
the National Metal and Materials Technology Center
(MTEC) and Pan ASIA Industrial Co., Ltd., Bangkok,
Thailand for supplying the materials and equipment
were used in this research.
References
[1] N. Kreua-ongarjnukool, K. Charmorndusit, S.
Pankumnead, J. Rotpradit, The impact modification of
poly(methyl methacrylate) sheet by using polyurethane,
Thai Patent 0701001014, 2007.
[2] K. Chamondusit, C. Sriprachuabwong, S. Pongchaloen, S.
Rodium, A study and preparation of transparent impact
styrene—methyl methacrylate by casting process, Thai
Patent 0601102635, 2006.
[3] L.H. Sperling, Interpenetrating Polymer Networks, 1st ed.,
John Wiley & Sons, Inc., New York, 2004, pp. 288-306.
[4] T. Jeevananda, I. Siddaramaiah, Synthesis and
characterization of polyaniline filled PU/PMMA
interpenetrating polymer network, European Polymer
Journal 39 (2003) 569-578.
[5] U. Witt, T. Einig, M. Yamamoto, I. Kleeberg, W.D.
Deckwer, R.J. Műller, Biodegradation of
aliphatic-aromatic copolyester: Evalution of the final
biodegradable and ecotoxological impact of degradation
intermediate, Chemosphere 44 (2001) 289-299.
[6] S. Panyadee, Recycling PMMA scrap in casting process,
B.Sc. Special Project, Department of Industrial Chemistry,
Faculty of Applied Science, KMUTNB (King Mongkut’s
University of Technology North Bangkok), Bangkok,
2008.
[7] C. Vancaeyzeele, O. Ficheta, S. Boileaub, D. Teyssie,
Polyisobutene-poly (methyl methacrylate)
interpenetrating polymer network: Synthesis and
characterization, Journal of Polymer 46 (2005)
6888-6896.
[8] P.S.O. Patricio, Effect of blend composition on
microstructure, morphology, and gas permeability in
PU/PMMA blends, Journal of Membrane Science 271
(2006) 177-185.
[9] ASTM D 256, Standard Test Methods for Determining the
Izod Pendulum Impact Resistance of Plastics, West
Conshohocken, PA, USA, 2010.
[10] ASTM D 6110, Standard Test Methods for Determining
the Charpy Pendulum Impact Resistance of Plastics, West
Conshohocken, PA, USA, 2010.
[11] M.R. Timmins, D.F. Gilmore, R.C. Fuller, R.W. Lenz,
Bacterial polyesters and their biodegradation,
Biodegradable Polymer and Packaging 11 (1993) 119-130.
[12] E. Marten, R.J. Műller, W.D. Deckwer, Studies on the
enzymatic hydrolysis of polyesters II aliphatic-aromatic
copolyester, Polymer Degradation and Stability 88 (2005)
371-381.
[13] J.P. Eubeler, M. Bernhard, S. Zok, T.P. Knepper,
Environmental biodegradation of synthetic polymer I. test
methodologies and procedures, Trends in Analytical
Chemistry 28 (2009) 1057-1072.