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1. PLASTICS
 Polyethylene
1) LDPE
2) HDPE
 Polypropylene
 PVC
 Polystyrene
 Nylon {Polyamide}
 Acrylic multipolymers
 Polyethylene terephthalate {PET}

2. Properties LDPE HDPE Polypropylene Polystyrene PVC
Density 0.91-0.925 0.95-0.96 0.89-0.91 1.0-1.1 1.2-1.4
Clarity Transparent Translucent Clear Clear Clear
Water
Absorption Low Low Low High Low
Permeability
to W. V. Low Very Low Very Low High
Moderate to
Low
Permeability
to Oxygen High
Moderate to
High
Moderate to
High High Low
Resistance to
Acids
Fair to very
good
Fair to very
good
Fair to very
good Fair to good Very good
Resistance to
Alkalies Good Good Very good Good Good
Resistance to
Heat Poor Fair Good Fair Fair to poor
Resistance to
Cold Excellent Excellent Poor to fair Poor Very Poor
Resistance to
Sunlight Fair Fair Fair Fair to poor Good
Resistance to
High humidity Excellent Excellent Excellent Excellent Excellent
Stiffness Low Moderate
Moderate to
high
Moderate to
high
Moderate to
high
Unit Cost Low Low Low Low Moderate

3. Properties LDPE HDPE Polypropylene Polystyrene PVC
Uses Cosmetics
Foods
Cosmetics
Foods
Detergents
Drugs
Milk
Cosmetics
Drugs
Syrups
Juices
Drugs
Petroleum
Jellies
Detergents
Shampoos
Bath oils
Whiskey &
wine
Floor waxes

4. Properties HDPE LDPE Polystyrene PVC Polypropylene Nylon Polycarbonate
Inertness Outstanding Excellent Very poor Poor Good Good Poor
FDA approval Yes Yes Yes Yes Yes Yes Yes
Advantages Inertness
Low cost
Low WVT
Inertness
Low cost
Squeeze
Low cost
Clarity
Stiffness
Clarity
Stiffness
O 2 barrier
Inertness
Low cost
O 2 barrier
Tough
O 2 barrier
Tough
Disadvantages Taste transfer High WVT High WVT
Cracking
Poor impact
Processing is
difficult
Brittleness Cost
Water
absorption
Cost
Cracking
Poor barrier