Polycarbonate Vs Polypropylene: What Are the Differences?

Comparing polycarbonate vs polypropylene will draw your attention to several key differences in the two plastic types. Although both polycarbonate (PC) and polypropylene (PP) share features like strength, heat resistance and chemical resistance, they have different star properties. 

PC is renown for its high impact resistance and transparency, used for products from optical lenses to safety helmets. PP is a common, cost-efficient plastic popular for food packaging, medical equipment, and beyond. The decision between polycarbonate vs polypropylene will come down to finding the material whose properties best align with the intended application!

Polypropylene (PP), also known as number 5 plastic, is recognized for its strength, flexibility, versatility, and affordability.

Structurally, polypropylene is a polymer: a chain-like molecule made up of repeating units (monomers), in this case propylene. It is a thermoplastic due to its ability to soften when heated and harden when cooled.

PP can be formulated differently for various intended applications. The two most common types of polypropylene are homopolymer (repeating monomers) and copolymer (2+ monomer types). PP homopolymer is the most widely-used, popular for packaging and textiles. PP copolymers tend to have increased impact resistance and are often used in automotive and medical device applications.

As the second most commonly produced plastic, PP is easily available and affordable compared to other plastic types. It is suitable for numerous applications, offering food-grade, chemically-resistant, and autoclavable qualities that make it valuable across industries from food to chemical to medical. 

Is polypropylene strong? PP is a strong plastic, capable of withstanding twisting motions of up to 360 degrees without snapping. Its tough elasticity is suitable for uses in which thin layers of plastic are frequently bent but not intended to break, like the lids of snap-top caps, hinges on flapper caps, and various toys and appliances. 

Polypropylene’s lightweight and durable body makes it excellent for cost-efficient storage and shipping. It also has a fibrous form which can be used in the production of textiles like clothes, thread, and carpets.

Untreated polypropylene has limited UV resistance and is highly flammable. Additives can be incorporated into the material to make it more resistant to UV rays and fire.

PP plastic’s surface is not easy to bond using conventional adhesives, so plastic welding is a popular alternative. Additionally, polypropylene may require surface preparation in order to bond with dyes, pigments, and printed designs.

Polycarbonate (PC) is a type of plastic recognized for its exceptional strength, impact resistance, and a clarity comparable to glass. The name is an umbrella term for a group of multiple polycarbonates, whose shared characteristics are similar enough to be collectively identified. PC plastic is classified as a number 7 plastic type, sharing the category with acrylic, nylon, fiberglass, and others.

So what is polycarbonate plastic? Like polypropylene, polycarbonate is also a polymer, traditionally created using the monomers phosgene and bisphenol A (BPA). As the safety of BPA continues to be evaluated by the FDA, some manufacturers offer BPA-free PC plastic. PC plastic is also a thermoplastic which softens with heat and hardens in the cold.

Polycarbonate boasts glass-like transparency while being more lightweight and impact resistant– capable of withstanding significant impact without shattering– than glass. This makes it an excellent material for optical lenses, safety goggles, and bullet-proof “glass”.

Due to its remarkable strength and moldability, PC plastic is frequently used for protective equipment such as helmets, shields, phone and laptop cases, car sunroofs and various other uses in automotive and construction industries. 

Is polycarbonate heat resistant? It is both heat resistant and fire resistant, liquefying at its melting point of 536°F - 608°F.

Polycarbonate is more costly than other plastics. Despite being impact resistant, polycarbonate is prone to scratching and may require an anti-scratch coating.

In recent years, the FDA has continued to evaluate the safety of BPA, adjusting suggested applications for PC plastic. They advise against using PC for baby bottles and sippy cups, while a larger push to avoid BPA for food & beverages sweeps the packaging world. Unless BPA-free, polycarbonate is no longer recommended for food applications.

Polycarbonate (PC) and polypropylene (PP) are reliable plastic types used in many of the same industries. However, they are formulated to meet different performance expectations. 

PC is a more expensive plastic option, typically used for its strength in automotive and construction industries, or its transparency in medical and electronic industries. Its toughness and strength are regarded as unbreakable, boasting resistance to high impact, corrosion, moisture, heat, and some chemicals.

PP is an accessible choice for versatile containers, parts, and equipment. It is lightweight and flexible, excellent for food packaging, medical containers, material handling, and alike. PP is resistant to chemicals, corrosion, moisture, heat, fatigue, and moderate amounts of impact.

At The Cary Company, we prioritize providing you with a rich selection of products. Shop polycarbonate vs polypropylene containers and find the ideal container for your intended application. Browse our versatile selection of plastic containers or explore industry-specific categories!

Have any questions? Interested in finding a container? Contact one of our product specialists available to answer any questions and recommend products for you. Give us a call at 630-629-6600 or email us at sales@thecarycompany.com.