Journal of Environmental Treatment Techniques  
2021, Volume 9, Issue 1, Pages: 233-241  
J. Environ. Treat. Tech.  
ISSN: 2309-1185  
Journal web link: http://www.jett.dormaj.com  
https://doi.org/10.47277/JETT/9(1)241  
Bio-Degradation Study of ABS Protein Filled Nano  
Composite  
1
1
2
M. Khaj , N. Goudarzian , Kh. Yousefi  
1
Department of Applied Chemistry, Faculty of Sciences, Shiraz Branch, Islamic Azad University, Shiraz, Iran  
Department of Materials Science and Engineering, School of Engineering, Shiraz University, Shiraz, Iran  
2
Received: 06/09/2020  
Accepted: 08/11/2020  
Published: 20/03/2021  
Abstract  
In this work we report the particular preparing as well as properties of nano blend according to acrylonitrile/butadiene/styrene  
terpolymer using improved nano silica, and also casein, in particular, most of us studied the effects of filler injections concentration on  
morphology, as well as hardware overall performance, paying attention our consideration on the consequence with the biodegradation  
phenomena with the casein modifiers. ABS/nano Si and casein blends are assumed to be biodegradable since both components are bio-  
degradable in a variety of microbial circumstances. The particular processing and mechanical properties involving casein and also  
ABS/nano Si blends have been well investigated and submitted to degradation by dirt interment tests in perforated boxes for 6 months  
and later analyzed. After destruction, blends along with casein displayed FTIR signals of minimal intensity in comparison to the original  
blends. These results exposed that ABS/nano Si’s biodegradability may be improved until casein is added to it. as to the actual mechanical  
properties, the effect of casein content on the strain at break of the nano composites, it is seen that the strain at break and impact strength  
of the nano composites get worse with the addition of casein where it decreases with increasing casein content while Young's modulus  
is higher than that of pure ABS.  
Keywords: Nano composites; Acrylonitrile/butadiene/styrene terpolymer; Bio-degradation; Nano Silica  
1
another widespread route is the basis on the development of  
1
Introduction  
nanocomposites (14-16). The original aims of nanoparticles  
addition to being able to immiscible polymer blends are  
generally how the morphology of the blends is usually affected  
by nanoparticles and also whether these types of additives can  
easily play the role of compatibilizer in the blends (17-19). It  
must be noted that the mechanism of action of nanoparticles to  
modify the actual morphology are investigated, we aimed to  
detect nano silica localization within an immiscible  
ABS/nanoSi blend nanocomposites applying the actual  
rheological. In this function, an endeavor was also meant to set  
up a correlation concerning localization involving nanosilica  
and it is an effect on morphology. The results revealed these  
rheological methods, especially the oscillation mode, were  
trustworthy tools to find clay-based localization specifically on  
high silica loading. From the morphological research, it had  
been identified which the localization associated with nano  
silica within the matrix phase of the mixes led to improved  
development in the morphology (20-24). Caseins are animal  
proteins and are commonly found in milk, making up 80 % of  
the proteins in cow milk and between 60 and 65 % of the  
proteins in human milk. Casein molecular weight is between  
The particular plastic-type industry offers knowledgeable  
some sort of exceptional progress over the last several years,  
and also parts have become found in every part connected with  
enterprise and also lifestyle. The actual important enhance  
inside pockets generation and also product or service era has  
brought in the also important enhance inside plastic material  
convenience. Plastic-type material waste materials, whoever  
the main source will be product packaging, is among the  
members towards waste materials administration difficulty  
acrylonitrile/butadiene/styrene terpolymer (ABS) plastic  
material is probably the many dominating packaging in  
addition to industrial supplies in today's modern society and it  
is unable regarding self-decomposition (1-4).  
Poly (Acrylonitrile/butadiene/styrene) (ABS) is usually  
semi crystalline thermoplastic polyester widely used in textile  
fibers making, food packaging as well as liquefied containers,  
thermoforming purposes as well as engineering resins  
frequently in combination with fillers during the past years (5-  
9
). There has been growing attention to some courses  
connected with the biodegradation plastic composites in which  
acquiescence to help the environment, and also  
nanocomposites, based on the dispersion of fillers at a  
nanometric scale. Among the various kinds of nanoparticles,  
lamellar fillosilicates just like montmorillonite and have been  
carefully investigated (10-13). Polymer blending is a useful  
method to beget materials with specific enhanced properties.  
The blending of polyolefins with engineering plastics is a path  
to improve the mechanical confidants of polymeric materials  
-1  
1
,000 and 20,000 g.mol . Caseins include four different types.  
Casein is the predominant protein and is characterized by an  
open, random coil structure. By treating acid-precipitated  
caseins with alkali solution, caseinates are produced. Both  
caseins and caseinates from transparent films from aqueous  
solutions without any treatment based on hydrogen bonds.  
Caseins have shown to be useful in a great number of fields  
*
Corresponding author: N. Goudarzian, Department of Applied Chemistry, Faculty of Sciences, Shiraz Branch, Islamic Azad  
University, Shiraz, Iran. E-mail: ngoudarzian@iaushiraz.ac.ir  
2
33  
Journal of Environmental Treatment Techniques  
2021, Volume 9, Issue 1, Pages: 233-241  
such as adhesives, controlled releases, and biomedical  
applications (25-28).  
under the air pressure for mechanical testing. The compositions  
of nanocomposites were 10, 15, 20 w% casein. For the  
mechanical tests of all nano composites with 3w% of nano, Si  
was collected. The optimum formula for biodegradable exams  
was obtained ABS 90 w% and casein 10w%, ABS 85 w%, and  
casein 15w% and finally, ABS 80 w% and casein 20 w% all of  
them have 3 w% nano silica.  
2
Experimental details  
2
. 1 Materials  
Styrene acrylonitrile (SAN), (SAN w1540) was supplied  
by Iran Petro Chemical Co., Ltd. (Iran), [MFR = 50 g/10 min  
3
(
200 °C /21.6 Kg), Density  
=
1.04 g/cm ] and  
2
.2 The scanning electron microscope (SEM)  
Utilize a focused beam of high-energy electrons to come up  
Styrene/Butadiene/Styrene (SBS) was supplied by Amole  
Plastic, Co, Ltd. Iran. Casein is a commercial material; it was  
brought from local suppliers and used as received, nano silica  
used in this study is commercially available as fine amorphous,  
nonporous, and typically spherical particles, white color,  
with a variety of signals in the surface area of stable  
individuals. The actual impulses that obtain via electron sample  
interactions reveal information about the sample including  
external morphology chemical composition, as well as  
crystalline structure and orientation of materials making up the  
sample. In most applications, data are usually collected over a  
chosen area of the surface of the sample, as well as a 2-  
dimensional picture is earned which demonstrates spatial  
variations inside these properties. Places ranging from  
approximately 1 cm to 5 microns wide could be imaged in a  
scanning mode using conventional SEM techniques. The actual  
SEM is also capable of executing examines of determining  
place spots for the sample, this method is especially helpful  
within qualitative. The degree of biodegradation  
ABS/Casein/nano Si blends ended up being measured using  
their weight fractions and the exploitation with the  
ABS/Casein/nano Si blends through separation this casein right  
after 6month.  
2
specific gravity 1.12, particle size 8-20 nm, SiO content 99.1%  
and glycerol (Gl) 99.5% was a commercial grade without any  
treatment. For the preparation of ABS nano composite from  
SAN and SBS and nano silica we used SAN and SBS granules  
that were mixed and deride at temperature 80-90 ºC for 6 h and  
ABS were prepared using a laboratory scale twine extruder  
(
DSE) (L/D=40, D=20 mm) which could be operated at  
different amount SAN/ SBS (5, 10, 20, 30, 40 w%) and amount  
of nano silica 1, 3, 5 w% at 160-190 ºC which could be operated  
at a constant speed (200rpm). The physical and mechanical  
study of these blends showed that the ABS with 20w% SBS  
and 3 w% have the optimized characteristics so we used this  
blends for biodegradation studies.  
Composites preparation ABS granules and casein powder  
were mixed manually and dried at temperature 110/125 ºC for  
a 6 h. To improve the mixing of the blend components, the  
casein was subjected to plasticization with glycerol. Glycerol  
was chosen as a softener because of its high plasticizing ability  
relative to that of casein and a quite satisfactory one relative to  
ABS, as well as because of its nontoxicity and rather high  
thermal stability. ABS/casein composites were prepared using  
a laboratory scale Double screw extruder (DSE) (L/D = 28, D  
3 Results and discussion  
3.1 Biodegradation  
3.1.1 Degradation soil burial test The soil burial tests started  
o
in October 2014 and continued for 6 months at 35±2 C in an  
environment in which the relative humidity was not less than  
85%. ABS/Casein/nano Si blends were buried in a perforated  
box to allow the samples to be attacked by the microorganisms  
and moisture. The box was buried at a depth of 7 ± 9 in. beneath  
the soil surface. After removal, all the samples were carefully  
washed to stop the degradation and the plastic sheets  
(thickness=0.423 mm) were stored in darkness until testing.  
The soil burial tests started in October 2014 and continued for  
6 months at 35±2 oC in an environment in which the self-  
relative moisture was not less than 85%. ABS/Casein/nano Si  
blends were buried in a perforated box to allow the samples to  
be attacked by the microorganisms and moisture. The box was  
buried at a depth of 7 ± 9 in. below the soil surface. After  
removal, all the samples were attentively washed to stop the  
degradation and the plastic sheets (thickness=0.423 mm) were  
stored in darkness until testing.  
=
20mm), which could be operated at different speeds, varied  
from 0 to100 rpm. The screw has a fluted type mixing section  
located before the metering zone (29) in this type of mixer the  
material is forced to pass at high shear stress. This brings in  
some level of dispersing action besides reorienting the  
interfacial area and increasing the imposed total strain. The  
flight depth of the screw in the metering zone was 1.56 mm,  
and the helix angle 17.7º. The temperatures profile along the  
barrel of the extruder were set at 160,160,160,190 °C (from  
feed zone to die), and the screw speed was 40 RPM. The  
composites were then extruded through a multi holes die (3  
mm) and the extrudes were left to cool in the air and then fed  
into a granulator which converted them into granules. The  
obtained granules were then dried at temperature 110/125°C for  
6
h before use. The prepared composites and ABS were  
compressed and the molding temperature for the composites  
and ABS were 200, 160 °C respectively. The molded  
specimens were then cooled to 80 °C before removal from the  
mold and cut into a dog bone - shaped sample (ASTM D638)  
3.1.2 Weight lost  
After 6 months the films and specimens calculated taking  
their weight fractions and the weight lost number present in  
table 1 and Fig. 1  
Table 1: Durations of weight loss of ABS with different amounts of casein  
SAMPLE (w 10% casein)  
0.671gr  
0.657gr  
0.638gr  
0.618gr  
SAMPLE (w 15% casein)  
SAMPLE (w 20% casein)  
0.675gr  
0.590gr  
0.567gr  
0.546gr  
First weight  
0.673gr  
0.621gr  
0.605gr  
0.578gr  
Weight after 2 months  
Weight after 4 months  
Weight after 6 months  
2
34  
Journal of Environmental Treatment Techniques  
2021, Volume 9, Issue 1, Pages: 233-241  
biodegradation is about the original samples. However, as the  
amount of casein is increased the degradability characteristics  
will increase. This data table 1 indicates that the part of the  
sample was not degraded during the soil burial test after 6  
months.  
0
.7  
10%weight of casein  
1
2
5w% weight of casein  
0w%weight of casein  
0
0
0
0
.68  
.66  
.64  
.62  
3
.2 Mechanical properties  
Fig. 2(a and b) shows the effect of casein content on the  
0
.6  
strain at break of the nanocomposites; it is seen in these figures,  
that the strain at break of the composites get worse with the  
increase of casein where it decreases along with increasing  
casein content, and also the presence of 15% of casein in the  
composite caused a steep decline in the strain at break.  
0
0
0
0
.58  
.56  
.54  
.52  
Fig. 3(a and b) shows the effect of protein content on  
Young's modulus for the composites, it could be noted from  
Fig. 3, that Young's modulus of the composites is higher than  
that of pure ABS. It could be said that the addition of protein to  
ABS follows the general trend for filler effects on polymer  
properties [36]. The modulus increases due to the stiffening  
effect of protein and the strain at break decrease sharply as the  
protein content is increased. The increasing casein content  
higher than 15% caused a sharp decrease in the stress at break.  
Figure 4 (a and b) shows the effect of casein content on the  
strain at break of the composites, it is seen in these figures, that  
the strain at break of the composites get worse with the addition  
of casein where it decreases with increasing casein content, and  
the presence of 15% of casein in the composite caused a steep  
decline in the strain at break.  
0
.5  
first weight weight after  
month  
weight  
after4month after6month  
weight  
2
Figure 1: Diagram of weight loss of ABS with different amounts of  
casein  
After the 6 months of soil burial test, the growth of  
microorganisms on the plastic caused changes in some of its  
physical and chemical properties that can be detected in the  
weight lost analysis. From the weight lost curves for  
ABS/Casein/nano, Si blends with glycerol, before and after  
buried for 6 months Fig. 1, it was verified that all the samples  
presented fewer stages of biodegradation after the period of soil  
buried test. It was observed that after the soil burial test,  
1
2
0
8
6
4
2
0
12  
10  
(a) Strain at break  
1
(b) Strain at break after biodegradation  
8
6
4
2
0
5
10  
15  
20  
25  
30  
5
10  
15  
20  
25  
30  
Protein content (wt%)  
Protein content (wt%)  
Figure 2: Strain at break versus casein content (0-30 w %); (a) before degradation (b) after degradation  
4
4
4
4
4
4
4
4
4
3
3
400  
350  
300  
250  
200  
150  
100  
050  
000  
950  
900  
4300  
4200  
4100  
4000  
3900  
3800  
3700  
(a) Young's modulus  
3600  
3500  
3400  
3300  
(
b) Young's modulus after  
biodegradation  
5
10  
15  
20  
25  
30  
5
10  
15  
20  
25  
30  
protein content (wt%)  
Protein content (wt%)  
Fig. 3 (a and b) Young's modulus versus casein content (wt. %); (a) before degradation (b) after degradation  
2
35