Polypropylene and polystyrene are two of the most common polymers used to manufacture plastic lab supplies and other materials. So what’s the big difference? We are here to help. In this blog we will discuss the main characteristics of the two types of plastic and what key benefits each of them offer.

Polypropylene

Polypropylene, also identified as PP, is a thermoplastic polymer commonly used to manufacture plastic laboratory supplies like beakers, bottles, flasks, specimen containers, test tubes, and many others. One of polypropylene’s key features is that it is exceptionally rugged and unbreakable. It also offers high resistance to many chemicals, acids, and bases. Many polypropylene products are autoclavable thanks to their increased level of heat resistance. Depending on the grade, polypropylene has a melting point of anywhere from 130 °C (266 °F) up to 171 °C (340 °F). Polypropylene plastic is opaque without color added, however, it is also available in clear.

Many polypropylene lab products are autoclavable. A great example of this would be polypropylene beakers and flasks. These common plastic lab containers can be reused over and over again without having to replace them. This offers a substantial cost savings benefit over their glass counterparts. However, there are still many applications where glass is preferred and necessary.

Polypropylene products are great for a large variety of uses and offer a low cost alternative to many other plastics and glassware products. They offer durability, exceptionally high chemical resistance, and can withstand extreme temperatures which makes them very versatile in many lab and industrial applications.

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Polystyrene

Polystyrene, also identified as PS, is one of the most widely used plastics across all industries and is produced in huge volumes. It is because of this that it is usually offered at a lower price point than many other plastics. General purpose polystyrene is clear, hard, and brittle and as a thermoplastic polymer it is in a solid glassy state. Polystyrene offers some resistance to acids and bases but it is not as resistant against some chemicals as polypropylene. As appearance goes, polystyrene products like test tubes and petri dishes are usually very clear and look much like glass. However, many of these polystyrene products can not withstand heat above 100°C making them less likely candidates for constant reuse. They are commonly disposed of after only a single use and are usually consumed in large quantities.

Polystyrene is great for general sample storage and transport and is commonly used in food grade packaging products and lab supplies like test tubes, microplates, and petri dishes.

Both plastics are interchangeable in many applications but as you can see there are some inherent differences between them that would be key to deciding whether or not they are suited for your use. As a general rule of thumb, we suggest carefully reviewing the product features and specifications before making your purchase, especially considering the many grades of polystyrene and polypropylene available on the market today.

Updated January 8th, 2020