Polystyrene: What’s the Difference Between HIPS and GPPS?

Find Out if HIPS or GPPS is Better for Your Polystyrene Application

Polystyrene (PS) is one of the most popular thermoplastic materials in the world, but depending on your application you’ll want to use High-Impact Polystyrene (HIPS) or General-Purpose Polystyrene (GPPS). Each has unique properties that should be taken into account before deciding which one is best for your project and end-user.

At Amco Polymers, offering our material expertise in product development is one of the solutions we pride ourselves on offering to our clients. Read on to learn more about which type of polystyrene you should consider for your end product.

What Do HIPS and GPPS Have in Common?

While there are some key differences between high-impact and general-purpose polystyrene resins, they do share several characteristics. Both are resins that are low-cost, rigid and easy to process and manufacture. These methods of processing include injection molding, extrusion, blow molding and thermoforming.

HIPS and GPPS are both FDA-compliant, making them very common in kitchenware and food packaging applications. These aren’t the only application categories they share, as they both can be used in healthcare and houseware applications as well.

These polystyrene resins have excellent aesthetics, good gloss and are easy to paint, glue and print on. HIPS and GPPS also each hold Underwriters Laboratory recognition 94HB and are recyclable.

Amco Polymers has HIPS and GPPS products available through our supplier relationship with Total Petrochemicals.

What are the Unique Qualities of High-Impact Polystyrene (HIPS)?

High-impact polystyrene is a polystyrene resin that’s used in lower heat applications. As its name suggests, HIPS has high impact strength and good dimensional stability. HIPS is easy to thermoform and can be printed using Digital, Screen, Flexo and Litho inks.

HIPS is naturally a white color and has a matte finish, and while it’s not naturally transparent, HIPS can be painted on and glued easily for excellent aesthetics. A good example of HIPS food packaging is yogurt cups.

Several HIPS grades are designed to have exceptional resistances for specific end-use, such as in refrigeration liners, toilet seats and tanks, or disposables that require high environmental stress crack resistance.

What are the Unique Qualities of General-Purpose Polystyrene (GPPS)?

While both GPPS and HIPS are considered low-cost, General-Purpose Polystyrene is the more cost-effective of the two polystyrenes. GPPS is brittle and has low-impact strength as well as less dimensional stability than HIPS.

Unlike HIPS, GPPS comes in either a slight blue edge or water clear edge tint. GPPS has a glass-like clarity that makes it popular in transparent food packaging, and it can be easily molded into different shapes. Because of this, GPPS is also a popular choice for plastic toy applications.

GPPS is also often used in refrigerator trays, boxes, cosmetic packs and CD cases.

Are you interested in TOTAL Polystyrene?

Known throughout the country and the world, Amco offers its customers the best, widest range of engineering polymers at the most competitive prices. Tell us about your polystyrene needs and we can select the right resin for your application, together.