Continental J. Biological S
© Wilolud Journals, 2012
Printed in Nigeria
EFFECTS OF STARCH BLEND ON
1
Department of Industrial Chemistry
ABSTRACT
The effect of corn and cassava st
polypropylene was studied using th
strength of the polymer decreased p
starch (90 % weight loss) and 0.5
addition. At the same rate, elongati
for corn starch (91 % weight l
biodegradability of a 10 % starch f
more than 70 % in the presence of t
KEYWORDS: Polypropylene, Star
________________________________
INTRODUCTION
Solid waste disposal especially non-bi
with the emerging large number of plas
are receiving attention mainly because
fillers in polyurethane (Bennett, et.al.,
(Otey et al., 1980).
As a way of solving the problem of wa
and environmental degradation (Potts, J
environmental pollution to limited sp
biotechnological approach to proffer b
makes use of micro-organisms such as
function through enzyme action to caus
first generation of biodegradable mater
starch. The second attempt concentrat
polymeric backbone. These groups wer
polymer. The third approach is the d
naturally synthesized by bacteria grow
polymers therefore means the applicat
polymer chain and subsequent disinte
however effective if the polymer mix co
Classical methods using the America
biodegradability showed that alteration
of drastic decrease in molecular weight
and Ono, R.1995) also proposed the so
In this method, the result of the biodeg
found to correlate with the result obtain
Potts screened a variety of materials an
such as starch, cellulose, cotton and si
micro-organisms secrete enzymes, whic
organic acid which the organism can re
20
Sciences 5 (1): 20 - 25, 2012 ISSN: 2141
2 http://www.wil
doi:10.5707/cjbiolsci.2012
THE MECHANICAL PROPERTIES AND BIODEGRAD
POLYPROPYLENE
1
A.O. Ogah and
1
J.N. Afiukwa.
y, Faculty of Physical Sciences, Ebonyi State University,
Abakaliki, Ebonyi State, Nigeria.
tarch blends on the mechanical properties and biodegr
he gravimetric (weight loss) method. The results showed
progressively from 2.497 Mpa of pure polymer to 0.250 M
500 Mpa for cassava starch (80 % weight loss) each at 5
ion at break also decreased from 1.087 % of pure polyme
loss) and 0.15 % for cassava starch (86 % weight
filled polymer composite within 30 days incubation was e
the micro-organism and it increased with incubation perio
rch, Biodegradation and mechanical properties.
_______________________________________________
iodegradable types constitute environmental problems.
stic industries in the country. Polymers filled with starch o
e of their biodegradability. Native and modified starch h
, 1967), polyvinylchloride (West Hoff et.al., 1974) an
aste plastic disposal, Potts, proposed recycling, incinerat
J.E.1978). However, these methods have their shortcomin
pace for effective landfills (Donnelly, B.2001). This
better solution to the problem of plastic waste disposal
s bacteria and fungi found naturally in the soil. These m
se biodegradation of plastic polymers (Gilead D.and Enni
rials consisted of blends of polymers with natural food s
ted on the insertion of functional groups, such as ester
re susceptible to microbial action due to the organic carbo
development of materials such as polyhydroxybutyrate
wn in fermentation pot (Bailey,W.JandGapud,B.1985).Bi
tion of micro-organisms on polymer mix to cause a br
egration of the molecular chain. The action of the mi
ontains some carbohydrates.
an Standard for Testing Materials (ASTM) and of test
n in tensile properties and complete loss of structural inte
t are evidence of biodegradation (Gilead. and Ennis, R.19
oil burial method as a way of testing for the biodegradabil
gradation of LDPE, PS, PVC and UF buried in the soil f
ned using the ASTM method.
nd discovered that micro organisms in the soil gobbled n
silk but ate up one class of synthetic polymer, the polye
ch seek the ester group and in aqueous medium converts
eadily digest (Potts, J.E.1960). It is believed that the abov
1 - 4122
loludjournal.com
2.5.1.20.25
ADABILITY OF
P.M.B. 053,
radability of
d that tensile
Mpa for corn
50 % starch
er to 0.10 %
loss). The
enhanced by
od.
___________
This is peculiar
or its derivatives
has been used as
and polyethylene
tion, composting
ngs ranging from
study applies a
l. This approach
micro-organisms
nis, R.1985). The
sources, such as
linkages on the
on content of the
(PHB) that are
iodegradation of
reakdown of the
icro-organism is
ting plastics for
egrity as a result
987). Otake, Y
lity of polymers.
for 32 years was
natural polymers
ester group. The
it to alcohol and
ve reactions