What are the different types of plastics?

According to Statista, the United States generated 35.7 million short tons of plastic wastein 2018 (12.2 percent of municipal solid waste that year). From packaging to finished products, plastic’s low cost and versatility have made it a modern staple.

Plastic products fall into these seven categories based on their composition:

• Polyethylene terephthalate

• High-density polyethylene

• Polyvinyl chloride

• Low-density polyethylene

• Polypropylene

• Polystyrene

• Other

Many plastics feature a recycling emblem that displays its plastic code, a number assigned to plastic to convey its resin content and recyclability.

Industrial recycling and waste management operations facilitate the reuse and proper disposal of plastic, keeping it within the circular economy and out of the environment. Baling wire secures dense bales of recycled plastic for efficient transportation and storage.

We’ll learn more about the types of plastics, their common uses, which plastics are recyclable, and which baling wire you should use during the recycling process.

The 7 plastic types explained

Plastic lumber, disposable diapers, and reusable water bottles demonstrate the wide range of products plastic can create. Let’s look at each plastic type.

Plastic #1: Polyethylene terephthalate

Polyethylene terephthalate (PET or PETE) is a popular thermoplastic polymer resin. It is strong, transparent, lightweight, impermeable, and thermally stable up to 130 degrees Celsius.

PETE/PET plastics are used to create these common types of plastic products:

• Food packaging (peanut butter jars, ketchup packets)
• Beverage bottles (soda bottles, water bottles)
• Textiles and fabrics
• Automotive parts
• Plastic films and sheets (such as Mylar)

PET/PETE is one of the most common plastics due to its versatility and recyclability. It is 100 percent recyclable and roughly 1.5 billion pounds are recycled in the US annually.

Plastic #2: High-density polyethylene

High-density polyethylene (HDPE) is a plastic resin. It is a linear polymer with little branching, which gives it stronger intermolecular forces and higher tensile strength than lower-density polyethylene. It has strong chemical and impact-resistant qualities.

Common HDPE products include:

• Bottles (milk jugs, bottle caps, detergent bottles, shampoo bottles)
• Natural gas lines
• Sewage pipes
• Cutting boards
• Outdoor furniture
• Floor tiles

HDPE is highly recyclable (up to roughly 10 times). It has a strong resistance to contamination, which simplifies recycling.

Plastic #3: Polyvinyl chloride

Polyvinyl chloride (PVC) is a synthetic plastic polymer known for its durability, formability, and resistance to fire and chemicals. It is the third most produced plastic due to its excellent qualities as a construction material.

Common PVC products include:

• Water pipes
• Insulation piping for electrical wires
• Automotive trim and underbody components
• Packaging materials

PVC is recyclable, but its chemical structure complicates the process. Sophisticated technology requirements contribute to PVC’s low recycling rate. Most PVC ends up in landfills or incinerators, where its harmful dioxins can pollute the air, soil, and waterways. Technological advances are reducing costs associated with PVC recycling efforts.

Plastic #4: Low-density polyethylene

Low-density polyethylene (LDPE) is a thermoplastic polymer made from the monomer ethylene. It is flexible, low density, translucent, and moderately resistant to chemicals and heat.

Common LDPE products include:

• Flexible containers (squeezable bottles, baby bottles)
• Plastic wrap (food wrap)
• Packaging (bread bags, chip bags, food wrappers)
• Molded laboratory equipment
• Shopping bags, trash bags, grocery bags

LDPE is recyclable, but most municipalities and recycling programs will not accept it. Recycled LDPE has such a low market value that it is a net carbon drain to process and recycle it, with transportation costs commonly exceeding the value of a bale. Thin plastic bags are also tedious to manually sort and can clog sorting equipment.

Plastic #5: Polypropylene

Polypropylene (PP) is a thermoplastic polymer made from the monomer propylene. It is a versatile plastic known for its light weight, temperature resistance, flexibility, and electrical insulation.

Common PP products include:

• Packaging and bottles
• Sterile medical equipment
• Textiles
• Consumer goods (toys, garden furniture, household items)

PP is a valuable and highly recyclable plastic, but many curbside programs don’t accept it because it clogs many types of recycling equipment. Instead, individuals must set aside PP plastics and take them to dedicated recycling facilities for processing.

Plastic #6: Polystyrene

Polystyrene (PS) is a synthetic aromatic polymer made from the monomer styrene. It is a transparent plastic with excellent rigidity, formability, and chemical resistance.

Common PS products include:

• Food containers (disposable plates, takeout packaging, yogurt containers)
• Building insulation
• Consumer goods (plastic cases, toys)
• Medical devices (medicine bottles, Petri dishes)
• Automotive accessories (knobs, trim, instrument panels)

PS plastic is 100 percent recyclable, but its low density makes it economically and environmentally inefficient. More carbon is wasted in transportation and recycling than is retrieved from recycled PS. In its foam form (Styrofoam), PS easily breaks apart and enters the environment.

Plastic #7: Other

Number seven plastics include all other types of plastic as well as plastic compounds. Some of the most common number seven plastics include:

• Polycarbonate (PC): a strong, transparent thermoplastic known for its impact resistance, used in eyeglass lenses.
• Polylactic acid (PLA): a biodegradable plastic derived from renewable materials such as corn starch, commonly used in food packaging.
• Acrylonitrile butadiene styrene (ABS): a tough, heat-resistant thermoplastic polymer, often used to make LEGO bricks. Among #7 plastics, it is more commonly recycled.
• Acrylic: a transparent thermoplastic offering a glass-like appearance with high impact strength, used in aquariums.
• Nylon: a strong, durable synthetic polymer with high heat resistance, used in manufacturing guitar strings.
• Fiberglass: a durable plastic made of glass fibers embedded in a resin matrix, commonly used in boat hulls.
• Bioplastics and compostable plastics: plastics derived from renewable biomass sources that can break down naturally, used in single-use applications (disposable cutlery, hot food containers).

Number seven plastics are usually not recycled or recyclable for several reasons:

• Not economically viable for recycling
• Made of compounds that can’t be effectively separated for reuse
• Biodegradable plastics don’t require recycling

You can check with your local recycling program to learn whether or not they accept number seven plastic items.

Why is it important to recycle plastic?

Plastic degrades slowly in the environment. As it does, it releases harmful chemicals that enter the soil, air, and water. These chemicals eventually end up in our food supply, some of which are linked to negative health outcomes and reproductive issues.

Plastic recycling efforts achieve the following goals:

• Reduce environmental pollution: Plastic contains toxic chemicals that negatively affect ecosystems at all levels.
• Reduce landfill waste: As the global population grows, landfills must be alleviated from unnecessary waste.
• Reuse valuable materials: Many plastics are 100 percent recyclable (multiple times), and they are cheaper than virgin plastics.
• Conserve resources: A circular economy allows efficient resource allocation, requiring less fossil fuel and other resources such as petroleum.
• Reduce greenhouse gas emissions: Recycling plastic produces fewer emissions than producing virgin plastics.
• Educate consumers and businesses: Recycling efforts highlight consumption rates and opportunities to use fewer more sustainable products.

Plastic recycling efforts contribute to economic sustainability and create circular economies that minimize waste and pollution.

What is the plastic recycling process?

Plastic undergoes the following process from initial use to reuse:

1. Collection and sorting: Plastic waste is collected and sorted at a waste material recovery facility. Different types of plastics are separated and prepared for recycling.
2. Baling process: Sorted plastic waste is compressed into dense bales.
3. Sale to processors: The plastic bales are sold to plastic processors or recycling facilities.
4. Arrival at processing destination: Once at the processing facility, plastic bales are prepared for the recycling process. This may involve re-baling smaller bales into mill-size bales.
5. Shredding and cleaning: The plastic bales are broken open and plastic waste is shredded into small pieces. These shreds are cleaned and filtered to remove impurities.
6. Granulation: The cleaned, shredded plastic is melted and formed into pellets.
7. Manufacturing new products: Plastic pellets are used to manufacture new products. Depending on the type of plastic, these recycled products range from new plastic bottles and plastic containers to outdoor furniture, textiles, and building materials.
8. Distribution and sale: Recycled products are distributed and sold to consumers, completing the recycling loop.

Not all plastic waste can be recycled due to contamination or the type of plastic.

What is the best baling wire for recycling plastic?

We carry several wire options for baling plastic. The best type of wire for baling plastic will also depend on storage conditions and duration. Here are some of the best options:

• Black annealed wire feeds smoothly through high-volume automatic baling machines that are commonly used in plastic recycling.
• Galvanized wire is less commonly used for baling plastic. But if your bales require long-term storage, the galvanizing process offers increased resistance to rust and corrosion to keep bales safe and secure.
• Single loop bale ties can be tied to different lengths to accommodate inconsistent bale sizes. They work with manual horizontal and vertical balers. We offer both black annealed and galvanized single loop bale ties. Galvanized bale ties offer enhanced abrasion resistance.
• Double loop bale ties are pre-cut to length for use in auto-tie balers. The double loop configuration accelerates the tying process, increasing productivity.

Our baling wire is made from high-quality US steel to provide plastic recycling operations with the tools they need to effectively bale, store, and transport plastic waste.