You might think that all plastics are the same, but this is definitely not the case. Look at a plastic bottle or plastic product, and you will find a triangle of arrows with a number placed in the center. This number identifies the specific resin code or rather the type of materials or polymers that were used to create the plastic. These numbers were assigned by the Society of the Plastics Industry, and these resin identification codes are known as SPI numbers.
In many parts of the country, items with a number one or number two are the only types accepted for municipal recycling programs. The number one indicates items that are made from the polymer polyethylene terephthalate or PET which includes soft drink bottles and water bottles. Biaxially oriented PET film is known more commonly as Mylar, and this is used for thin, flexible food packaging and other products. Thermoforming is used to create these products, which begin, as a large sheet of thin plastic. Heat is applied, and the plastic is formed to a mold, then cooled and trimmed to create a finished product.
Plastics with a resin code or recycling code of two include many commonly used products, such as milk jugs, plastic grocery bags, food storage containers, hula hoops, parts of snowboards and the plastic that is used to build playground equipment. The polymer used to make No. 2 plastics is high-density polyethylene, and it is also known as HDPE. Interestingly, this HDPE plastic has been used to help with facial reconstructive surgery, which is certainly a true form of "plastic" surgery.
Polyvinyl chloride, which is used to produce items such as children's toys, lawn chairs, shower curtains and plastic bottles which do not contain food, has a resin code of three. It is also used to create pipes, and most people known it better by the abbreviation PVC. Number four plastics, which are abbreviated as LDPE, are created with low-density polyethylene and include many types of laboratory equipment because they offer excellent resistance to acids, bases and alcohols. Some computer hardware is made with LDPE plastic, as well as those plastic rings that hold together cans of soda or other beverages.
While it might not seem like diapers and carpet have much in common, both contain a bit of resin number five, which is polypropylene. This is a durable polymer which is also used to make bottle tops, such as flip tops on ketchup or salad dressing, as well as furniture. Because it is fairly heat resistant it can be used in laboratories, as well. Polystyrene is yet another type of polymer, and it is marked with resin code six and is often known by the brand name of Styrofoam. But generic versions of this polymer are used to create a variety of containers and cups, as well as packing peanuts that keep items safe in parcels during transit.
Strangely, there is no number eight, but there is a seven and a nine. Seven contains items that were created from an assortment of plastics, as well as nylon products and acrylic products. Nine is called ABS or acrylonitrile butadiene styrene, and it is very hard and durable and used to make Legos as well as musical instruments, pipes, golf club heads and much more.
In many parts of the country, items with a number one or number two are the only types accepted for municipal recycling programs. The number one indicates items that are made from the polymer polyethylene terephthalate or PET which includes soft drink bottles and water bottles. Biaxially oriented PET film is known more commonly as Mylar, and this is used for thin, flexible food packaging and other products. Thermoforming is used to create these products, which begin, as a large sheet of thin plastic. Heat is applied, and the plastic is formed to a mold, then cooled and trimmed to create a finished product.
Plastics with a resin code or recycling code of two include many commonly used products, such as milk jugs, plastic grocery bags, food storage containers, hula hoops, parts of snowboards and the plastic that is used to build playground equipment. The polymer used to make No. 2 plastics is high-density polyethylene, and it is also known as HDPE. Interestingly, this HDPE plastic has been used to help with facial reconstructive surgery, which is certainly a true form of "plastic" surgery.
Polyvinyl chloride, which is used to produce items such as children's toys, lawn chairs, shower curtains and plastic bottles which do not contain food, has a resin code of three. It is also used to create pipes, and most people known it better by the abbreviation PVC. Number four plastics, which are abbreviated as LDPE, are created with low-density polyethylene and include many types of laboratory equipment because they offer excellent resistance to acids, bases and alcohols. Some computer hardware is made with LDPE plastic, as well as those plastic rings that hold together cans of soda or other beverages.
While it might not seem like diapers and carpet have much in common, both contain a bit of resin number five, which is polypropylene. This is a durable polymer which is also used to make bottle tops, such as flip tops on ketchup or salad dressing, as well as furniture. Because it is fairly heat resistant it can be used in laboratories, as well. Polystyrene is yet another type of polymer, and it is marked with resin code six and is often known by the brand name of Styrofoam. But generic versions of this polymer are used to create a variety of containers and cups, as well as packing peanuts that keep items safe in parcels during transit.
Strangely, there is no number eight, but there is a seven and a nine. Seven contains items that were created from an assortment of plastics, as well as nylon products and acrylic products. Nine is called ABS or acrylonitrile butadiene styrene, and it is very hard and durable and used to make Legos as well as musical instruments, pipes, golf club heads and much more.
About the Author:
Lenna Stockwell enjoys blogging about how stuff is made. For further information about retail product packaging or to find out more about food packaging design, please go to the Indepak site today.
No comments:
Post a Comment