Polystyrene Packaging

Polystyrene is a very common material used in the packaging industry due to its easy processability, rigidity, low costs and excellent clarity (Crystal PS). As a material, polystyrene is available with three different molecular architectures:

• As a homopolymer referred to as crystal polystyrene because of it clarity and stiffness.
• As a blend with either grafted or blended rubber or other elastomers known as impact modified polystyrene.
• As a copolymer with butadiene (K-Resin)

Like most plastic sheet products, Polystyrene can also be modified with different additives to achieve certain characteristics. As a general rule, you can refer to the following guidelines.

Advantages of Polystyrene

• Low cost material.
• Excellent clarity.
• Excellent gloss.
• Excellent stiffness.
• Low shrinkage rates during thermoforming.
• Easily processed, wide melting point.

Disadvantages of Polystyrene

• Poor solvent resistance.
• Brittle unless impact modified.
• Subject to environmental stress cracking.
• Low vicat-softening temperature.
• Not suitable for microwave applications.
• Not suitable for freezer applications.
• Poor barrier properties.
• Poor taste and odor migration resistance.