It is no news that we need to preserve the earth for posterity’s sake. Global warming, a direct consequence of pollution, remains an existential threat to our planet. The danger of poorly disposed plastic to the biodiversity of aqua life is also one of the biggest concerns right now.
Plastic is thus of utmost importance to environmentalists, the government, and organizations, as plastic alone contributes about 12% of global waste. It is impracticable to eliminate plastic use due to its widespread use and the high costs of alternatives. Recycling hence remains today, our most viable option.
What is Recycling?
Recycling collects otherwise trash materials, processes them, and turns them into new reusable products. The concept was born of a need to make our resources renewable and reduce pollution. The benefits of recycling are numerous, with almost no downside. They include;
- It helps reduce the quantity of waste disposed of in landfills and incinerators.
- It conserves natural resources.
- It reduces environmental pollution by non-biodegradable waste.
- Economic benefits; it creates jobs and reduces the cost of manufacturing.
- It saves energy.
There are several recyclable products, for example, plastic, aluminum, glass, paper, trash bags, metal scraps, etc.
Plastic recycling however occupies a front row in the recycling industry. The reason is not far-fetched. According to a report in 2016, over 420 million tons of plastics are manufactured yearly across the globe. Plastic is everywhere. Just looking around you, you can effortlessly point out ten plastic products.
Have you thought of how much plastic you use in a day? The list is non exhaustive, from your coffee Styrofoam, to water bottles, trash bags, plastic cutlery, disposable lunch packs, ice cream containers. Unfortunately, this durable, lightweight material is not biodegradable; plastics take hundreds of years to degrade!
On the bright side though, a vast majority of plastic is recyclable! So, while your environmental concerns about plastics are valid, luckily for us, recycling takes care of these concerns.
How Are Plastics Made?
There are different types of plastic manufacturing processes: plastic injection moulding, rotational moulding, extrusion blow moulding, reaction injection moulding, vacuum casting, and injection moulding.
However, plastic injection molding remains the technique of choice responsible for over 80% of plastic manufacturing. It has the advantage of being used to make large quantities of identical products very quickly. It is the method of choice for large-scale production.
Curious about what materials are used in injection moulding? Well, a sizable quantity is from recycled plastic. Conversely, Plastics derived from injection moulding are recyclable.
At Allmould Plastics Pty Limited, we are specialists in plastic injection moulding, and some of the plastics used in injection moulding include;
- Acrylonitrile butadiene styrene (ABS)
- Acrylic, also called Plexiglass (PMMA)
- Nylon (PA)
- Polycarbonate (PC)
- Polyoxymethylene (POM)
- Polyetherimide (PEI)
Different Types Of Plastics and their Plastic Resin Codes
All plastics are not the same; about six types are commonly found in our daily products. These plastics are attributed plastic resin codes 1 to 7 by the manufacturer. The numbers allow you to quickly identify what kind of plastic the product contains.
- Polyethylene terephthalate (PET) – It is assigned number 1
- High-density polyethylene (HDPE)- number 2
- Polyvinyl Chloride, also known as Plasticized Polyvinyl Chloride (PVC)- number 3
- Low-density Polyethylene (LDPE)- number 4
- Polypropylene (PP)- number 5
- Polystyrene (PS)- number 6
- Others – The number 7 is assigned to plastics that don’t fall into any of the earlier listed 6 types.
The Most Commonly Recycled Plastics
As much as recycling remains a viable option to preserve our environment from the ills of plastic waste, amongst other benefits, not all plastics are recyclable.
We’ll however take a look at the most commonly recycled plastics. They are;
- Polyethylene terephthalate (PET) – 1
It constitutes a considerable part of our daily plastic use. It is the commonest polyester polymer. The high flexibility of PET plastic makes it a suitable candidate for water bottles, soda bottles, shampoo bottles amongst many household products. It is also a favorite in industries, used for electronics and automotive molded parts and 3D printing.
The wide application of PET is not unrelated to its superiority to some other plastics. It has been approved as safe by the FDA for contact with food and is also resistant to microwave radiation. PET remains the most widely recycled plastic.
- High-density polyethylene (HDPE) – 2
It is a thermoplastic polymer made from petroleum. It is a versatile plastic material. It has found application in the food industry, plastic surgery, 3D printing, etc.
Examples of products include; snowboards, facial reconstruction, shoe lasts, shampoo bottles, plastic jugs, and pipes. It has an advantage of a high melting point and stability to high impact.
- Polypropylene (PP) – 5
It is a challenging and crystalline thermoplastic, usually found in medical devices, Battery cases, and household products like furniture fabric. It is very light and resistant to alkali and acids.
At specialist facilities, some plastics are recyclable. The plastics in this category are generally not recycled in all recycling plants due to the techniques required and the cost. They are referred to as being somewhat recyclable.
- Polyvinyl Chloride (PVC) – 3
It is the third most widely produced plastic in the world. There is the rigid and flexible type. It is also commonly found in pipes, wire and cables, and medical equipment.
It is widely applicable in the construction industry; used in making doors and window profiles, and is quickly replacing conventional building materials like concrete, wood, and metal.
It is lightweight, durable, inexpensive, and highly resistant to heat chemicals and corrosives.
- Low-density polyethylene (LDPE) – 4
It is hard and corrosive resistant, not applicable where temperature resistance is required. It is found in prosthetics, orthotics, socket interfaces, etc.
- Polystyrene (PS) – 6
This is the plastic in your Styrofoam cups, disposable food packs, plastic cutlery. It is also found in laboratory wares, toys, electronics, and automobile parts combined with other plastics.
- Acrylonitrile butadiene styrene (ABS)
It is an opaque thermoplastic (that is, it can be melted to liquid form). It is thermoplastic; hence, it can be reheated multiple times, making it great for recycling.
It is a prime plastic in injection molding. Its application is limitless, cutting across several industries.
- Other recyclable plastics include; nylons, polycarbonate, and acrylic.