Five Common Types of Plastic Resins and Their Uses
In our world today, we are often surrounded by plastics, or commonly known as plastic resins. The popularity and overwhelming use of plastic resins are attributed to the fact that their properties and design technologies provide their customers with benefits beyond any other materials.
Plastic is often an extremely efficient material to choose than alternatives. This is because plastics are incredibly energy efficient to manufacture and because they are lighter than alternative materials. In this article, we will be looking into the different types of plastic resins as well as what they are used for: –
1. High Density Polyethylene (HDPE)
- HDPE is the one of the most widely used types of plastic, and used to make many types of bottles and containers.
- Unpigmented bottles are translucent, have good barrier properties and stiffness, and are suitable for packaging products with a short shelf life like milk.
- Due to the fact that HDPE has a good chemical resistance, it is often used for packaging many household and industrial chemicals like detergents and bleach.
- Pigmented HDPE bottles have better resistance against stress crack than unpigmented HDPE.
- Properties of HDPE:
- High resistance to most solvents
- Better performing tensile strength compared to other forms of polyethylene
- Relatively stiff material with beneficial temperature capabilities
- HDPE are often used in packaging applicants such as:
- Milk bottles, water bottles, juice bottles, cosmetic bottles, shampoo bottles, dish and laundry detergent bottles and household cleaner bottles
- Groceries and retail purchases plastic bags
- Cereal box liners
2. Polyethylene Terephthalate (PET, PETE)
- Polyethylene Terephthalate is clear, tough, and has good gas and moisture barrier properties.
- This resin is normally used in beverage bottles and many injection-molded consumer product containers.
- Cleaned and recycled PET flakes and pellets are in great demand for repurposing into spinning fiber for carpet yarns and producing fiberfill and geotextiles.
- Properties of PET include: –
- Clear and optically smooth surfaces for oriented films and bottles
- Great barrier to oxygen, water, and carbon dioxide
- Has a high impact capability and shatter resistance
- Great resistance to most solvents
- High capability
- PET is often used to produce in packaging appliances such as: –
- Plastic bottles for soft drinks, water, juice,mouthwash, and salad dressing
- Food jars for peanut butter, jelly, jam, and pickles
- Ovenable film and microwavable food trays
3. Polypropylene (PP)
- PP has good resistance against chemicals, it is strong and has a high melting point, which makes it good for hot-fill liquids.
- This resin is often found in flexible and rigid packaging, fibers, and large molded parts for automotive and consumer products.
- Polypropylene has many properties, such as: –
- Great optical clarity in biaxially oriented films and stretch blow molded containers
- Low moisture vapor transmission
- High resistance toward acids, alkalis, and most solvents
- Polypropylene is often used in producing packaging appliances like: –
- Containers for yogurt, takeout meals, and deli foods
- Medicine bottles
- Bottle caps and closures
- Bottles for catsup and syrup
4. Polystyrene (PS)
- Polystyrene is a flexible plastic that can be rigid or foamed, and is clear, hard, and brittle.
- Polystyrene has a relatively low melting point, which is often used to produce applications such as protective packaging, food service packaging, bottles, and food containers.
- PS is often combined with rubber to make High Impact Polystyrene (HIPS) which is used for packaging and durable applications that need toughness, but not clarity.
- Polystyrene has many properties, such as: –
- Great moisture barrier for short shelf life products
- Has excellent optical clarity in general purpose form
- Significant stiffness in both foamed and rigid forms
- Low density and high stiffness in foamed applications
- Low thermal conductivity and great insulation properties in foamed form
- Polystyrene is often used to produce: –
- Food service items, like cups, plates, bowls, cutlery, hinged takeout containers (clamshells), and rigid food containers such as yogurt
- These items may be produced with foamed or non-foamed PS.
5. Low Density Polyethylene (LDPE)
- LDPE is used predominantly in film applications because of its toughness, flexibility, and relative transparency, which makes it popular for use in applications where heat sealing is necessary.
- LDPE is used to manufacture some flexible lids and bottles and in wire and cable applications.
- LDPE has a number of properties, like: –
- High resistance to acids, bases, and vegetable oils
- Toughness, flexibility, and relative transparency
- Great combination of properties for packaging applications that require heat-sealing
- LDPE is used on producing packaging appliances such as: –
- Bags used for dry cleaning, newspapers, bread, frozen foods, fresh produce, and household garbage
- Shrink wrap and stretch film
- Coatings for paper milk cartons and hot and cold beverage cups
- Container lids
- Squeezable bottles
Overall, it can be difficult when choosing plastic resins for your packaging. By knowing which type of plastic resins is suitable for your project, it will be beneficial to promote your branding. Tai Hong Plastic Industries Sdn Bhd offers the best customer service and plastic resin pellets of high quality.