Plastic is an extremely versatile substance that can be molded, pressed or extruded to form solid objects of varying shapes and sizes. Its nature allows it to take on a wide range of forms, making it suitable for use in everything from food containers to building materials and electronics. Plastics are produced from petroleum-derived polymers that are subjected to various processes involving heat and pressure in order to produce the desired results. Because of their unique properties, plastics are categorized in many different ways. Some of these categories are based on the physical properties of the plastic (eg, resistance to heat) while others are based on the manufacturing process used.
In addition, certain plastics can be categorized by their safety for humans and the environment. These are known as biodegradable and/or compostable plastics. Plastics that are categorized as such are marked with the number 7. This category is a catch-all for any other plastics that don’t fit into one of the six other categories and typically includes things like acrylonitrile butadiene styrene (ABS) and polycarbonates.
Polyethylene is the most widely used type of plastic in the world and it comes in three main types: High-Density, Low-Density and Linear Low-Density polyethylene (LDPE). LDPE is flexible but strong and can be found in many grocery bags as well as disposable utensils. It also has a high melting point and can resist fatigue, which makes it perfect for items like plastic wrap, frozen food packaging and squeezable bottles. It is also a very clean and safe plastic for human and animal contact.
High-Density Polyethylene is tough and has good moisture resistance. It is commonly found in milk cartons, detergent and cleaning product bottles, buckets and park benches. It is also used in construction materials like pipes and ducting. It is a highly durable plastic that can be recycled into new products.
PET is a clear and lightweight plastic with excellent moisture resistance. It is found in beverage bottles, plastic film and squeezable containers for foods such as margarine, ketchup and yogurt. It can be recycled into fibers for clothing, carpets and guitar strings. It also has an outstanding strength-to-weight ratio.
Polyvinyl Chloride (PVC) is a hard, rigid plastic that is brittle and can withstand chemicals. It is very resistant to weathering and corrosion and doesn’t conduct electricity. PVC is dangerous for human and animal health because it leaches toxic chemicals that are known to cause cancer, birth defects and other medical problems.
Most plastics we throw away carelessly end up in the ocean, where they can harm marine life and are a significant contributor to pollution. These toxic chemicals leach into the soil and water, which in turn harms plant growth and reduces agricultural yields. The best way to help protect our planet and ourselves from these dangers is to limit or eliminate our use of plastic. Using less plastic is a healthier choice for everyone, but it is even more important to recycle the plastics we do use.