Why Some Plastics Are Non Recyclable?
Plastic is the common term for a broad range of synthetic or semi-synthetic organic materials used for manufacture of a variety of domestic and industrial products. Plastics are typically long chains of high molecular weight, that may contain other chemicals and substances to develop better performance. There are two mainly types of plastics, thermoplastic and thermoset plastics. Thermoplastics are heat sensitive plastics which if exposed to heat, melt in a few minutes. Whereas Thermoset plastics retain their shape until they are burnt completely.
Plastics are durable and degrade very slowly or are either non biodegradable in nature. Billion tons of plastic has been discarded and may persist for hundreds or even thousands of years. Burning of plastic is not a good idea. It releases harmful toxins into the air much more so than allowing them to degrade. Release of harmful fumes adds to the air pollution. Also, the manufacturing of plastics often generates large quantities of chemical pollutants that are harmful. The plastics industry release large amounts of toxic pollutants, greenhouse gases, dump of biodegradable and non-biodegrable landfill impacts.
Today almost every product is either made from plastics or has plastic components, but they all are not recyclable. Though every type of plastic has a recycling code, it does not mean that they have a recycling capability. Following is a general list of items which can be recycled along with those that are to be avoided for recycling:
Recyclable plastic items:
1. Packaging bottles which previously containing non-toxic liquids, haircare and bodycare products, soap, laundry detergent and other household detergents.
2. Packaging containers previously containing food (e.g., yogurt, margarine).
3. Lids toilet paper bags & paper towel bags, food packaging (unsoiled) & grocery bags bread bags, dry cleaning bags.
Non recyclable plastic items:
1. Polystyrene containers (all #6 plastics).
2. Containers previously containing solvents, paint, motor oil.
3. Toothpaste tubes, anything made with rubber, toys, tools & housewares.
The standards codes of plastics:
Plastic manufacturers willingly mark codes to recognize the variety of base chemical of plastic for recycling/sorting purposes. Plastics marked with a 3, 5, 6, and 7 are currently not recyclable in our area.
1. PET or PETE (Polyethylene terephthalate): the most frequently recycled plastics. Containers marked with a “1” are some plastic peanut butter jars, soft drink bottles, water bottles, plastic wrap, and salad dressing bottles.
2. HDPE (High-density polyethylene): A type of recyclable plastic, marked with a “2,” is frequently recycled. it includes some plastic juice bottles, milk cartons, shampoo bottles, and liquid detergent containers.
3. PVC (Polyvinyl chloride): A type of recyclable plastic, marked with a “3,” is less commonly accepted for recycling. It includes some liquid detergent containers, clear food packages, and many construction applications including some traffic cones. PVC containers frame approximately 5 to 10 % of plastic bottles manufactured in industry. Containers made of PVC are generally opaque and look like HDPE containers.
4. LDPE (Low density polyethylene): These are marked with a “4,” and are a type of recyclable plastic is used in some bread and frozen food bags, trash cans, and garbage can liners. About 75% of LDPE is manufactured to make a light, flexible film.
5. PP (Polypropylene): Another plastic that is commonly used in the automobile and building industries, it is marked with a “5” that are recyclable and include some car battery casings, and plastic drinking straws etc.
6. PS (Polystyrene): It is a recyclable plastic, marked by a “6,” includes some packing foam, protective packaging for electronic goods and toys.
7. Other: The word “Other” indicates that the package or container is made from a resin other than 1 through 6 or it is made from more than one resin. It is typically used to make three and five gallon reusable bottles.
What make Plastc Non-Recyclable:
While there are many types of plastics, not all of them can be recycled, recycling plastics has proven difficult. The problem is that it is difficult to automate the sorting of plastic waste, and so it’s labor intensive. Chemically few of plastics are somewhat crystalline and somewhat amorphous at molecular morphology, giving them a critical temperature point to melt down on heating and glass transitions points that induce molecular flexibility. Hence the chemical bonding and inter molecular structure determines the pattern of degradation. Stronger lattice structure results in non recyclability of plastics. It is the molecular bonds that make plastic so durable make it equally resistant to natural processes of degradation.
What Can We Do with Non-Recyclable Plastic?
1. Only a few types of all plastic products can be recycled, and reprocessed. Most plastics can only be reprocessed into plastic fencing or will go to landfill.
2. Reusing is a better option for plastics, we can always reuse the bread bags as produce bags when you go to the grocery or buy bulk foods.
3. We can save clean plastic bags and use them as padding and packaging materials.Category: Chemistry, Science