This document provides an overview of polymeric food packaging materials. It discusses the history and evolution of packaging from skins and leaves to modern materials. The key types of polymeric materials used in food packaging are described, including polyolefins, polyvinyl chloride, polyesters, nylons, polystyrene, and polycarbonate. Properties, applications, and testing methods of these materials are summarized. The packaging industry is growing significantly with increasing global demand and consumption.

1. ( P O L Y M E R I C F O O D P A C K A G I N G M A T E R I A L ’ S )
Food Packaging Material
Presented by : Prakash Kumar
(Ph.D. Research Scholar, AGFE,
IIT-Kharagpur)
prakashfoodtech@gmail.com

2.  Packaging has been with humans for thousands of years in
one form or the other. Packaging dates back to when people
first started moving from place to place.
 Originally, skins, leaves, and bark
were used for food transport.
Four thousand years ago, sealed pottery jars were used to
protect against rodents, and glass making was an important
industry in Egypt.
INTRODUCTION : “Packaging Material”

3. One hundred years ago there was little use for packaging in
the food industries.
 Now, tremendous progress has been made in the
development of diversified packaging materials and in the
packaging equipment.
 Tin-plating iron became possible in AD1200, and as steel
replaced iron this method became useful.

4. Packaging performs five main functions:
Product containment
Preservation and quality
Presentation and convenience
Protection during Distribution and Processing
Provide storage history

5. Ideal packaging material:
Zero toxicity
High product visibility
Strong marketing appeal
Ability of moisture over a large temperature range
Low cost and availability
Stable performance over a large temperature range
Suitable mechanical strength and suitable strength
Easy machine handling and suitable friction coefficient
Closure characteristics, such as opening, sealing and resealing
Ability to include proper labeling
Resistance of migration of leaching from package
Protection from loss of flavor and odor
Controlled transmission of required or unwanted gases etc.

6. Packaging material selection is based on:
 technical properties (strength, flexibility, etc.)
 fitness for purpose (moisture barrier, cushioning, etc.)
 availability
 manufacturing capability
 cost
 environmental impact
 regulations

7. Types of Packaging Materials :
From skins, leaves, and bark, tremendous progress has been
made in the development of diversified packaging materials
and in the packaging equipment.
In general, Packaging Materials may be grouped into :
1- rigid (wood, glass, metals, and hard plastics )
2-flexible (Plastic film, foil, paper, and textiles )

8. INDUSTRY OVERVIEW
(Reference : A Report on Plastic Industry (Jan,2016) by FICCI with
knowledge and strategic partner TATA Strategic Management Group.)
Packaging is one of the fastest growing industries and stands at USD 700
billion globally.
The Indian packaging industry constitutes ~4% of the global packaging
industry and which is growing 18% p.a. wherein flexible and rigid packing
is expected to grow at 25% and 15% respectively.
The per capita packaging consumption in India is low at 4.3 kgs, compared
to developed countries like Germany and Taiwan where it is 42 kgs and 19
kgs respectively.
Indian packaging industry is valued at over USD 32 Bn and offers
employment to more than 10 lakh people across the country through
~10,000 firms.

9. Packaging in general is classified into two significant types i.e.
Rigid Packaging and Flexible Packaging.
Estimated

10. Polymeric Packaging
Material

11. Webster’s dictionary definition:
It is a complex organic compounds
produced by polymerization, capable of
being molded, extruded, cast into various
shapes and films, or drawn into filaments
and then used as textile fibers.
COMPOSED PRIMARILY OF A BINDER WITH :
•P L A S T I C I Z E R S
•F I L L E R S
•P I G M E N T S
•O T H E R A D D I T I V E S
What is plastic?

12. Why plastic?
 A wide variety of different qualities :
-Rigid V/s Flexible
-clear V/s opaque
Light weight – high product to package ratio.
Cost
Inert
Chemically resistant

15. Based on polymerization process and molecular
structure, Polymeric materials classified into :
a) Polyolefins – Polyethylene and Polypropylene (PP)
b) Polyvinyl group - Polyvinyl Chloride (PVC)
c) Condensation – Polyester (PET), Nylon-6 or Polyamide
(PA)
d) Styrene Polymers – Polystyrene (PS) and Expanded
polystyrene (EPS)
e) Carbonate group – Polycarbonate (PC)
f) Ethylene vinyl alcohol
g) Coated films
h) Laminated films
i) Coextruded films

16. a. Polyolefins – flexibility, strength, lightness, stability, moisture and
chemical resistance and easy processability and are suited for recycling and reuse.
 POLYETHYLENE :
 LDPE (Low-Density Polyethylene)
 LLDPE(Linear LDPE)
 MDPE(Medium DPE)
 HDPE(High DPE)
 HMHDPE(High Molecular
High DPE)
 POLYPROPYLENE :
Physical Properties
Durable
 High elongation
 300%
 High Tensile Strength
 4500 psi
 High Yield Strength
 4000 psi
High Melting point
Low Density
 Lowest density of all
plastics used in packaging

17. b. Polyvinyl Chloride (PVC)
 Hard
 Brittle
 Transparent material
 Low GTR
 Moderate WVTR
 Good resistance to fat and oil
 Glass like clarity contains twice amount
 Good mechanical strength of Chlorine as PVC
 Retention of flavor
 Resistance to chemicals
 Excellent printability
 Lower weight/volume ratio
Polyvinylidene chloride:
excellent barrier to water vapor,
gases, and fatty and oily products.
E.g. poultry, cured meats, cheese,
snack foods ,tea, coffee and
confectionary product packaging

18. c. Condensation polymer: formed from ester monomers
that result from the reaction between carboxylic acid and alcohol or
condensation reaction b/w diamine and diacid (repeating unit held by amide link)
Polyester :
Gloss, low gas and
moisture permeability,
high mechanical
strength, light weight,
chemically not react etc.
PET or PETE:
Glass like transparency,
good resistance to heat,
oils, solvent and acids but
not to bases . E.g., Bottles,
jars, tubes, trays, bags and
snack food wrappers
It exists both as
Amorphous and a semi-
crystalline form.
Polyethylene napthalate:
It having high glass transition
temperature and it is far more
better than PET but more costly
nearly 3 to 4 times.
Eg. Beer etc

19. Polyamide or Nylon-6 :
Formed by a condensation reaction between diamine and
diacid and the repeating units are held together by amide links.
E.g. Nylon-6
Used in packaging, high mechanical strength,
high elongation capability, excellent resistance to
cutting, perforation, abrasion and bursting, high
chemical resistance to oils and fats, it has mechanical
and thermal properties similar to PET.

20. d. Styrene polymers :
 Polystyrene (PS ) :
It is not flexible like LDPE
and PP. It is hard in nature
Properties:
Rigidity and dimensional
stability.
Resistance to chemicals
Easy processing
Good barrier to moisture
and ability to take post
moulding decorations
 Expanded polystyrene( EPS)
it is neither flexible nor rigid. It’s
cushioning in nature. Commonly
known as “thermocole”.
Properties :
Densities varies from 20-30kg/cm3
Stresses at 10% compression is 1 to
1.4 kg/cm2.
Tensile strength is from 2.5 to 3.2
kg/cm2.
Thermal conductivity at 100 ⁰C is
0.028 k.cal.m/hr.m2
Does not provide breeding ground for
fungi, bacteria or insects

21. e. Carbonate group :
 Polycarbonate is formed by polymerization of a sodium salt of
bisphenol acid with carbonyl dichloride (phosgene).
Properties :
Clear
Heat resistance
Durable
It is mainly used as a replacement for glass in items such as large
returnable/refillable water bottles and sterilizable baby bottles.
caution!! harsh detergents such as sodium hypochlorite is not
recommended because they catalyze the release of bisphenol A

22. f. Ethylene vinyl alcohol (EVOH):
 It is copolymer of ethylene and vinyl alcohol.
 It is an excellent barrier to oil, fat and oxygen.
 It is moisture sensitive and is thus mostly used in
multilayered co-extruded films in situation where it
is not in direct contact with liquids.
EVOH

23. g. Coated films :
 Films are coated with other polymers or aluminum to
improve the barrier properties or to import heat
stability.
nitrocellulose coating.
vinyl acetate or vinyl chloride coating.
Aluminum coating.
Properties :
Sleeves of this materials are tough.
Stretchable
Permeable to air, smoke and moisture.
(packaging meat before smoking and cooking)

24. h. Laminated films :
 Two or more materials (plastic/paper/aluminum) are
laminated together to improve the barrier properties of
the packaging material.
 Bonding is commonly achieved by use of water, solvent
or solids based adhesives.
 Printing buried between layers and thus not subject to
abrasion.

25. Types of laminates Food application
Polyvinylidene Chloride coated
polypropylene ( 2 layers)
Crisps, snack foods,
confectionery, ice cream,
biscuits, chocolate
Polyvinylidene chloride coated
polypropylene polyethylene
Bakery products, cheese,
confectionery, dried fruit,
frozen vegetables
Cellulose-polyethylene-cellulose Pies, crusty bread, bacon,
coffee, cooked meats,
cheese
Cellulose-acetate-paper-foil-
polyethylene
Dried soups
Metallised polyester-polyethylene Coffee, dried milk
Polyethylene-aluminium-paper Dried soup, dried
vegetables, chocolate

26. i. Coextruded films :
 Simultaneous extrusion of two or more layers of
different polymers.
Properties:
Very high barrier properties.
They are thinner than laminates.
The layer do not separate.
lower cost.

27. Types of coextrusion Food application
High impact polystyrene-
polyethylene terephthalate
Margarine, butter
cubs/tubs
Polystyrene-polystyrene-
polyvinylidene chloride -
polystyrene
Juices, milk bottles
Polystyrene-polystyrene-
polyvinylidene chloride-
polyethylene
Butter, cheese, margarine,
coffee, mayonnaise, sauce
tubs and bottles

28. Testing of polymeric Packaging Material :
 Thickness test (mm)
 Tear strength test
 Heat seal strength test
 Bursting strength test (unit : psi)
 Tensile Strength test{unit : lb/(width or thickness)}
& Elongation test (unit : %)
 Gas transmission test (unit : cc/100 in^2 /24hrs)
 Water vapour transmission test (unit : grams/100
in^2/24hrs)
 Grease resistance test (time i.e. min. or hrs, required for 1st
appearance of stain on the packaging material.
 Aging test

29. References :
 Report on “Plastic Industries” 2016 by FICCI with help of
knowledge and strategic partner TATA strategic and managemet
group.
 Galić, K., Ščetar, M., & Kurek, M. (2011). The benefits of
processing and packaging. Trends in Food Science &
Technology, 22(2-3), 127-137.
 Mahalik, N. P., & Nambiar, A. N. (2010). Trends in food
packaging and manufacturing systems and technology. Trends in
food science & technology, 21(3), 117-128.
 Kadoya, T. (Ed.). (2012). Food packaging. Academic Press.
 Berger, K. R. (2003). A brief history of
packaging. EDIS, 2003(17).