glycerol being added as compatibilizers displayed good water vapor barrier property
and also lowered the glass transition temperature [13].
Biodegradable films can be also manufactured by utilizing oxidized or acetylated
arracacha starch. Due to the high transparency displayed by films produced from
acetylated starch, also because of their good physicochemical properties, these can
be used for food packaging applications [14].
The biodegradable packaging film was produced by blending sugar palm starch
with plasticizers like sorbitol, glycerol, etc. Water vapor permeability values were
observed in the increased range of 4.855 Â 10
À10 to 8.70 Â 10
À10 g
À1 s
À1 Pa
À1
irrespective of the plasticizer types in films [15]. Starch can be transformed into
foamed material through water steam, thereby substituting polystyrene foam for
packaging purposes. The processed material can be transformed into trays and
disposable dishes by pressing. The products produced were nontoxic and easily
biodegradable in the microbial environment within short period of time leaving CO 2
and water as by-products [16]. Novament produces its own starch blends, and it is
one of leading company in manufacturing starch-based products [4].
2.1.1 Starch Composites
Starch-based polymers have displayed deprived mechanical properties and high
water vapor permeability when compared with synthetic plastics. Microcrystalline
cellulose (MC), carbon nanotubes, carboxymethylcellulose (CMC), nanoclays,
fibers, etc. were added to starch-based polymers to improve their properties
[8, 17]. The polymer blends produced by blending PLA, PCL, and starch have
shown better biodegradation in natural environment when compared to pure
PLA [18].
2.2 Cellulose
Cellulose is formed from linear chain of glucose molecules linked by highly polar
and hydrophilic glycosidic β(1–4) bonds, and it is the most commonly found
biopolymer in nature. Cellulose acts as structural component in plant materials,
fungi, sea animals, and some amoeba [19]. As cellulose-based films are costeffective and completely biodegradable, they offer immense scope in replacing
petrochemical based plastics [20].
As cellulose are hydrophilic in nature, it encompasses a high crystalline structure
and poor solubility, and it is difficult to use them as such for food packaging. But this
can be solved by manufacturing cellulose derivatives through esterification reactions
where cellulose are derivatized in the solvated state, thereby making it fit for
packaging applications. The additives of cellulose esters like cellulose (tri)acetate
and cellulose (di)acetate were previously added to convert them into thermoplastic
materials. Cellulose ethers like ethyl cellulose when added with plasticizers could be
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B. Srinivasan and G. Kulshreshtha
and also lowered the glass transition temperature [13].
Biodegradable films can be also manufactured by utilizing oxidized or acetylated
arracacha starch. Due to the high transparency displayed by films produced from
acetylated starch, also because of their good physicochemical properties, these can
be used for food packaging applications [14].
The biodegradable packaging film was produced by blending sugar palm starch
with plasticizers like sorbitol, glycerol, etc. Water vapor permeability values were
observed in the increased range of 4.855 Â 10
À10 to 8.70 Â 10
À10 g
À1 s
À1 Pa
À1
irrespective of the plasticizer types in films [15]. Starch can be transformed into
foamed material through water steam, thereby substituting polystyrene foam for
packaging purposes. The processed material can be transformed into trays and
disposable dishes by pressing. The products produced were nontoxic and easily
biodegradable in the microbial environment within short period of time leaving CO 2
and water as by-products [16]. Novament produces its own starch blends, and it is
one of leading company in manufacturing starch-based products [4].
2.1.1 Starch Composites
Starch-based polymers have displayed deprived mechanical properties and high
water vapor permeability when compared with synthetic plastics. Microcrystalline
cellulose (MC), carbon nanotubes, carboxymethylcellulose (CMC), nanoclays,
fibers, etc. were added to starch-based polymers to improve their properties
[8, 17]. The polymer blends produced by blending PLA, PCL, and starch have
shown better biodegradation in natural environment when compared to pure
PLA [18].
2.2 Cellulose
Cellulose is formed from linear chain of glucose molecules linked by highly polar
and hydrophilic glycosidic β(1–4) bonds, and it is the most commonly found
biopolymer in nature. Cellulose acts as structural component in plant materials,
fungi, sea animals, and some amoeba [19]. As cellulose-based films are costeffective and completely biodegradable, they offer immense scope in replacing
petrochemical based plastics [20].
As cellulose are hydrophilic in nature, it encompasses a high crystalline structure
and poor solubility, and it is difficult to use them as such for food packaging. But this
can be solved by manufacturing cellulose derivatives through esterification reactions
where cellulose are derivatized in the solvated state, thereby making it fit for
packaging applications. The additives of cellulose esters like cellulose (tri)acetate
and cellulose (di)acetate were previously added to convert them into thermoplastic
materials. Cellulose ethers like ethyl cellulose when added with plasticizers could be
112
B. Srinivasan and G. Kulshreshtha