Today's Date: 15 February 2025

Recycling plastic

The last half of the 20th century has been dominated by plastic in terms of product packaging, as is the 21st century now. Aside from everyday use packaging, a great variety of products now contain plastic, from cheap toys to textiles and expensive electronic devices. As a petroleum based material, it is cheaper to produce than others and comes in numerous variations, used according to their particular properties.

The material used in manufacturing items such as jars and bottles used to be glass, but nowadays the market has been taken over by plastic, which brings a few advantages. Whilst it can provide the same visual effects as clear or coloured glass, it is not easily breakable, thus it is far more durable, suits more types of environments and is safer to use.

Compared to wood, which it is also replacing in a great number of applications, plastic is far more durable and is rarely damaged by UV rays, insects or rodents; it does not suffer cracks or splinters. Also, it does not rot and excellently withstands the conditions of a water based environment (constant exposure to water and at times algae). It shows the best resilience when being exposed to the natural elements, which is why a range of items providing protection from them are always made from variants of plastic, such as umbrellas, parasols and outdoor covers (for furniture, cars etc.).

Moreover, it is less flammable than wood and involves lower maintenance costs and labour. Akin to newly produced plastic, recycled plastic possesses all these qualities and can be successfully used in an equally large and diverse array of applications.

Types of plastic

Plastic is classed according to its precise chemical composition as well as physical properties, into many categories, the most commonly found on the market being the following.

Polyethylene, with a few variations

PET – Polyethylene: This particular sort usually ends up in landfill as it is widely used within the food and drinks industry for the packaging of everyday use items, such as beverages. Due to its resistance, airproof and waterproof qualities, it is regarded as highly hygienic and safe for the long term preservation of food as well as drinks. It is also a suitable replacement for glass in manufacturing jars.

HDPE – High density polyethylene: As the name suggests, the denser structure of this material makes it suitable for items requiring increased resilience, such as pipes, buckets or large water containers. It is also used within the food and drink industry in the manufacturing of small containers for holding beverages such as fruit juice, cosmetics and toiletries. It is also viewed as safe as it doesn’t contaminate products.

LDPE – Low density polyethylene: Also a non-contaminant, this type of plastic strongly differs from the previous to categories of polyethylene through its physical properties. It is extremely flexible, as opposed to the first two types, which are rigid. Akin to them, it is predominantly used for storing food (from frozen food bags to containers for foods of a viscous consistency, such as mustard or spreadable cheese). The thickness of the sheets used varies greatly according to the products they are destined for. Also, the rigidness and thickness are directly proportional.

Polyvinyl chloride(PVC): This material is used for a multitude of purposes, its physical properties differ according to its particular type. Tens of tons are produced each year and its applications are very diverse, from the construction industry to the textile one, which employs it to produce weather-proof clothing and outdoor covers. It is also used for making inflatable toys etc. and packaging, in its least dense and most flexible variation.

Polypropylene(PP): This is the most commonly used material for kitchenware, as it is non-toxic and highly resistant to most possible contaminants, such as grease and chemicals. It is also very durable, difficult to break and very easy to clean, which makes it the ideal candidate for intensely used cooking containers. It is also used within the food and drink industry for packaging (such as soft cheese tubs and similar items).

Polystyrene(PS): Polystyrene is very widely used in the UK due to the predilection for fast food and take away meals, as it is used for manufacturing a large array of disposable food and drink containers. People don’t usually bother recycling such items and and it tends to end up in landfill. It is less resilient than other types, very light and in most forms, easily compressed. Other common applications are in packaging.

The recycling process

Plastic can be recycled through a number of processes, which differ in efficiency and costs. The process starts with the collection phase, which is the case for all recyclables. Then, plastic items are sorted according to their polymer types and sometimes according to their colour (that is usually the case for polyethylene bottles). The items are often baled before being transported to a recycling facility, for convenience. They are then washed and shredded and subsequently undergo a purification process, which eliminates unwanted materials (such as labels or bottle caps, on polyethylene bottles).

The plastic is then melted and turned into new items, or pelletised. The most frequent processes used are depolymerisation, heat compression and monomer recycling. Whilst for heat compression all types of plastic are suitable and can be recycled together, it is deemed less effective due to the high levels of energy use involved.

Recycled plastic items

Objects made frommaterials such as paper and glass are generally recycled into similar items, yet when it comes to plastic, it suffers surprising variations, in terms of turning from a type of plastic of a certain consistency, properties and colour to a completely different type. When recycled plastic is not used for manufacturing new objects, it often goes into construction and landscaping products, some companies specialising in this.

These products vary form car parking, walkways and ground protection to fencing and street furniture. For instance, high density polyethylene is often recycled into fake lumber, which imitates the appearance of timber, its applications including decking, benches etc. The process of turning polyethylene (PET) into thread or yarn, to use for making durable, weather resistant polyester, is becoming increasingly popular.

An original initiative

Plastic bottles are bought and emptied daily by the thousands and very often end up in landfill, as many tend to be consumed outdoors and left in street bins once empty. Generally, if there isn’t a plastic recycling bin nearby when the bottles have to be discarded, consumers won’t hold on to them until they find one, but will throw them in the nearest rubbish bin instead. Reverse vending machines constitute a recycling initiative similar to that of paying bottle or can deposits and getting them back when returning the recyclables.

These devices basically accept empty beverage containers, including plastic bottles, and release a small amount of money or a voucher in return for the items, in order to stimulate more people to participate. They can be found in many public places across Europe and the US.

The benefits of recycling plastic

Due to its enhanced durability, which exceeds that of other materials such as wood, plastic poses a major waste problem as most of it is not biodegradable (except for specially designed products such as plastic bags which decompose within a certain period of time and are customarily offered in supermarkets). It is also more likely to be thrown away as plastic items tend to be fairly cheap and thus easily replaced. When household use items such as kitchen utensils or gardening tools are damaged, most people prefer throwing them away to fixing them, which might leave them prone to breaking again.

Also, the vast majority of disposable items are made from plastic (such as vending cups, party plates and so forth). Recycling plastic, whatever the type, is the optimal way to solve this incessant waste problem. Also, considering the fact that plastic is obtained from petroleum, recycling is a way to save a significant percentage of this valuable resource.