High-impact polystyrene (HIPS) is the rubberreinforced polystyrene plastic which exhibits significantly enhanced impact strength compared to pure polystyrene, while maintaining the main properties of polystyrene such as ductility and reasonable price. It has been widely used in daily equipment. There are two phases in HIPS: polystyrene continuous phase and rubber-dispersed phase. HIPS is usually synthesized by bulk free radical polymerization.

Structure

Structure HIPS consists of long chains of polystyrene in which fine particles of a rubber polymer are distributed. These particles act as a kind of “shock absorber” and prevent cracks from propagating in the polymer.

Properties

HIPS has a combination of properties that make it a versatile and widely used material. It is rigid, impact-resistant, lightweight, easy to process, and has a low melting point. HIPS is also resistant to chemicals, oils, and grease. HIPS has a tensile strength of 24.8 MPa (3,600 psi) and tensile modulus of 1.8 GPa (261 ksi) according to ASTM standards, this plastic is capable of withstanding enough force to make it a suitable choice for the packaging industry, and many other products as well.

Applications

From the grocery store to the packaging plant to the factory floor, this versatile plastic is a staple across all sorts of sectors. Some examples are:

• Knives, forks, and spoons in the food grade industry use HIPS Plastic.
• Elongated profiles found on display stands are created from HIPS Plastic.
• Containers and trays in the packaging industry
• HIPS plastic makes lightweight tubing and profiles common to household goods
• High Impact Polystyrene creates molded parts used to assemble toys

Because of its low cost and high machinability, HIPS plastic is often used as a replacement for molded zinc in many industrial applications. It can even be found in the transportation industry, as it’s a common component in several aircraft and automotive parts.

Adavantages

• more environmentally friendly than other plastics
• High Impact Resistance
• Highly Malleable
• Ability to Paint
• Affordable Price

Disadvantages

• HIPS is vulnerable to degradation by many chemicals, including solvents, acids, and alkalis.
• HIPS has a low-temperature resistanceand can become brittle at low temperatures.
• HIPS has limited resistance to UV lightand can become yellow and brittle over time when exposed to UV light.
• HIPS has poor flame resistanceand will ignite and burn easily.