This document discusses the resin identification coding system used internationally to identify different types of plastic polymers. It provides details on 7 common plastic codes: 1) PETE (polyethylene terephthalate) used for water/soda bottles and fibers; 2) HDPE (high density polyethylene) for milk jugs and detergent bottles; 3) PVC (polyvinyl chloride) for pipes, flooring, and furniture; 4) LDPE (low density polyethylene) for bags and food packaging; 5) PP (polypropylene) for yogurt containers and bottle caps; 6) PS (polystyrene) for disposable food packaging and cups; 7

1. By: Aubrey Vale Sagun

2. Codes and
Symbols in
Recycling of
Ethene base
addition
Polymer

3. The SPI resin identification coding
system is a set of symbols placed
on plastics to identify the polymer
type. It was developed by the
Society of the Plastics Industry (SPI)
in 1988 and is used internationally.

4. Plastic bottles are marked at their base
with the Resin identification code to
indicate the material used:

5. PETE
Polyethylene
Terephthalate
Formula: (C10H8O4)n
IUPAC ID: poly(ethylene)
(terephthalate)
PETE/PET
- is the most common thermoplastic polymer
resin of the polyester family and is used in
fibers for clothing, containers for liquids and
foods, thermoforming for manufacturing, and
in combination with glass fiber for engineering
resins.
Properties:
Usually clear or green, sinks in water, rigid,
glossy
Environmental Qualities:
Recycled into fleece coats, carpet, surf boards
Examples
Soda bottles, furniture

8. HDPE
High-Density
Polyethylene
Formula: (C2H4)n
- is the most widely used resin for plastic
bottles. This material is economical, impact
resistant, and provides a good moisture
barrier. HDPE is compatible with a wide range
of products including acids and caustics but is
not compatible with solvents. It is supplied in
FDA-approved food grade.
Properties:
HDPE is naturally translucent and flexible, semi
rigid
Environmental Qualities:
Recycled into plastic lumber, picnic tables
Examples
Milk, water jugs, juice, bleach bottles
HDPE

10. PVC/V
Polyvinyl
Chloride
Formula: C2H3Cl
- is an odorless and solid plastic. It is most
commonly white but can also be colorless or
amber. It can also come in the form of white
powder or pellets. PVC is made from vinyl
chloride.
Properties:
Semi rigid, sinks in water, glossy
Examples
Pipe, Window profile, Siding, fencing, flooring,
shower curtains, lawn chairs, non-food bottles
and children's toys.
PVC

12. LDPE/PE-LD
Low Density
Polyethylene
Formula: C2H3Cl
- is a thermoplastic made from the monomer
ethylene. It was the first grade of
polyethylene, produced in 1933 by Imperial
Chemical Industries (ICI) using a high pressure
process via free radical polymerization.
Properties:
Flexible, not crinkly
Examples
Frozen food bags; squeezable bottles, e.g.
honey, mustard; cling films; flexible container
lids.
LDPE

15. PP
Polypropylene
Formula: (C3H6)n
- is used primarily for jars and closures and
provides a rigid package with excellent
moisture barrier. One major advantage of
polypropylene is its stability at high
temperatures, up to 220 °F (104 °C).
Polypropylene offers the potential for steam
sterilization.
Properties:
Semi rigid, low gloss, strength, toughness, resistance
to heat, chemicals, grease and oil, versatile, barrier
to moisture.
Examples
Reusable microwaveable ware; kitchenware;
yogurt containers; margarine tubs; microwaveable
disposable take-away containers; disposable cups;
soft drink bottle caps; .
PP
IUPAC ID: poly(propene)

17. PS
Polystyrene
Formula: (C8H8)n
- is a synthetic aromatic polymer made from
the monomer styrene. Polystyrene can be solid
or foamed. General purpose polystyrene is
clear, hard, and rather brittle. A synthetic resin
that is a polymer of styrene, used chiefly as
lightweight rigid foams and films.
Properties:
Easily formed, often brittle, glossy
Examples
Egg cartons; packing peanuts; disposable cups,
plates, trays and cutlery; disposable take-
away containers. Styrofoam
PS
IUPAC ID:
poly(1-phenylethene-1,2-
diyl)

19. Polycarbonate
ABS
Acrylonitrile
butadiene
styrene
- is a synthetic aromatic polymer made from
the monomer styrene. Polystyrene can be solid
or foamed. General purpose polystyrene is
clear, hard, and rather brittle. A synthetic resin
that is a polymer of styrene, used chiefly as
lightweight rigid foams and films.
Properties:
Dependent on polymers or combination of polymers
Examples
Beverage bottles; baby milk bottles. Non-
packaging uses for polycarbonate: compact
discs; "unbreakable" glazing; electronic
apparatus housings; lenses including
sunglasses, prescription glasses, automotive
headlamps, riot shields, instrument panels
(often polycarbonate or ABS)