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A brief history of the major plastic polymers

Plastics are such a vital part of modern life; we have become unaware of how much we rely on them every day. However, many plastic polymers have only been around for a few decades. Life before these innovative materials was very different. They have made modern living simpler and safer, thanks to their durability, affordability and versatility.

The first major discovery of a plastic polymer was made in 1862. Since then, new polymers have been developed and discovered continuously – rapidly increasing from the end of the 1920s. Here is a brief history of each of the major plastic polymers and how they have changed the way in which we live.

Parkesine 

First developed in 1862, Parkesine was the first man-made plastic. It’s inventor, Alexander Parkes, revealed the plant-based polymer at the Great International Exhibition in London. Parkesine is a transparent and mouldable plastic that retains its shape when cooled. It was first marketed as a cheaper alternative to rubber, allowing users to mould and create whatever they needed.

Celluloid

In 1865, John Wesley Hyatt developed a new way to make billiard balls from cellulose nitrate. This material was far cheaper than the traditional ivory balls. Soon afterward, companies began manufacturing numerous products from celluloid, such as bowls and combs, as a cheaper alternative to bone, tortoiseshell and other expensive materials.

Rayon

This modified celluloid polymer was developed in Paris by Louis Marie Hilaire Bernigaut in 1891. He was looking for a way to manufacture a substitute for silk – a polymer that could be extruded into thin, shiny strands and woven together to form a silky fabric. Bernigaut called the polymer rayon because it had a shiny appearance that reflected rays of light.

Bakelite

In 1907, a completely synthetic plastic was developed that retained its shape and form, even under stress and heat. Bakelite became extremely popular in the 1920s when numerous products were manufactured from the polymer. Plastic jewellery, telephones and clocks became popular as people embraced the unique appearance of Bakelite.

Cellophane

Cellophane was invented by a Swiss chemist in 1912 who was looking to create a waterproof tablecloth. Later, in 1927, cellophane was used to wrap sweets and candies which really punted its use in the food industry to new heights. This moisture-resistant polymer kept the sweets fresh for longer as water vapour in the air could not affect the sugary treats within the wrapping.

Vinyl

Polyvinyl chloride (PVC or vinyl) was developed in the 1920s to replace natural rubber. It quickly became known as one of the most versatile plastics. It is commonly used to make medical tubing, plumbing pipes and construction products. PVC can be both rigid and flexible, which was why it became so popular in a number of industries.

Polyethylene

This widely-used plastic was first developed in the 1930s in the United Kingdom. Polyethylene is the most popular polymer to date and is the mainstay of modern packaging. It is used to create polyethylene terephthalate (PET) beverage bottles, high-density polyethylene (PE-HD) containers and low-density (PE-LD) shopping bags. 

Polyvinylidene Chloride

Not to be confused with PVC, this polymer was discovered by accident in 1933. It was initially used to protect military and naval equipment from the effects of saltwater at sea due to its ability to cling to other materials and form a protective barrier. Polyvinylidene chloride is also used as a protective film for food packaging and is marketed as “Saran wrap”.

Nylon

This polymer changed the entire textiles and clothing industry. Nylon was developed in 1939, after which DuPont unveiled women’s stockings made from nylon at the World Fair in New York. Nylon quickly became an affordable man-made alternative to silk and cotton, finding particular use in military clothing during World War II.

Polyester

Polyester was first discovered in the 1940s, but only gained significant popularity in the 1950s. DuPont marketed a new fabric under the name “Dacron”, which was simply woven polyester strands. This became the first washable synthetic fabric and the textile industry has never been the same.

Polypropylene

Polypropylene (PP) came about in the 1950s but it began with a legal battle over its true inventors. It is a highly-versatile plastic that is used to manufacture a variety of moulded products, such as dairy tubs for butter and ice cream, plastic furniture, buckets, car bumpers, fibres and woven cloth. It can be used in almost all plastic applications.

Polystyrene foam

Also called expanded polystyrene, this polymer was developed in 1954 by Dow Chemicals. The company introduced the polymer under the brand name “Styrofoam” and was marketed as a lightweight protective packaging product. It is used to make packaging peanuts, takeaway food containers and coffee cups.

These polymers have become so widely used that we don’t even notice the importance of plastics in our daily lives. The innovations that led to the development of some of these products are often underappreciated. Plastics have a vital role to play in modern living, the economy and even the environment.

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Plastics SA represents all sectors of the South African plastics industry. ​Together with our associations, we play an active role in the growth and development of the industry and strive to address plastics related issues, influence role-players and make plastics the material of choice.

​Plastics SA has been mandated to ensure a vibrant and sustainable plastics industry in South Africa. The plastics sector is uniquely placed to meet the needs of a sustainable society and to deliver solutions to many challenges such as recycling, climate change, water scarcity, resource usage and energy recovery.

For more news, updates and information on the South African plastics industry, follow us on Facebook, Twitter, Instagram, YouTube, LinkedIn and Pinterest.

Plastic packaging type 6 – PS

Plastics are highly valuable materials that make modern life possible. They keep our goods protected, our food fresh and are vital for the functioning of daily life, whether we are aware of it or not. Plastic packaging has many advantages, including economic benefits and ease of recycling or reuse. Plastics need to be recycled properly in order to maximise their economic value and to minimise their environmental impact.

To understand more about plastics, we will shed some light on the different types of polymer, their benefits and their recyclability properties, including what products can be made from recycled plastic. We will go according to the material identification codes found on plastics. These are numerical symbols from one to seven that are used to identify the type of plastic.

This coding system is used around the globe by recyclers, waste management companies and plastics manufacturers. It enables them to separate and sort plastics so that they can be processed according to the main polymer present. All plastic packaging should display these material identification codes. The sixth polymer used for plastic packaging is polystyrene (PS).

What is PS?

Polystyrene is a lightweight polymer that comes in two types; high-impact polystyrene (HIPS) and expandable polystyrene (PS-E or EPS). It was first sold commercially in the 1930s as an economic plastic to enhance food hygiene and extend product shelf-lives. PS is commonly used in the food and beverage industry as takeaway containers, vegetable punnets, disposable cutlery and plastic cups. PS is also recycled into lightweight cement blocks for the building industry.

Its lightweight nature makes PS an energy-efficient plastic to produce with a low carbon footprint. This plastic is in high demand by recyclers as it is used to manufacture seedling trays, combs, rulers, picture frames and clothing hangers. It is the sixth-most processed polymer by South African recycling facilities. Due to the well-established waste collection network and the fact that plastic food and drink containers form a large portion of our waste, 5572 tonnes of lightweight polystyrene packaging were recycled in 2018 alone. 

Benefits of PS packaging

PS has numerous unique characteristics that make it a valuable packaging material. The two types of polystyrene have different applications. HIPS is a transparent and semi-flexible plastic that is used to make fruit and vegetable containers (like grape punnets) as well as CD cases. PS-E is a foam-like polymer that is used to make vending cups, meat trays (like boerewors punnets) and cooler boxes.

PS is heat-resistant and acts as a good insulator – hence its widespread use in the food and beverage sectors. It is fairly easy to recycle and can even improve the aeration in landfills if it is not sent to a recycling facility. The furniture and domestic housewares markets are the two largest consumers of PS recyclate.

PS is non-toxic and non-reactive, so it can be used in food and beverage contact applications without affecting the consumer. These characteristics and benefits make PS a highly-valuable plastic packaging material in South Africa.

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Plastics SA represents all sectors of the South African plastics industry. ​Together with our associations, we play an active role in the growth and development of the industry and strive to address plastics related issues, influence role-players and make plastics the material of choice.

​Plastics SA has been mandated to ensure a vibrant and sustainable plastics industry in South Africa. The plastics sector is uniquely placed to meet the needs of a sustainable society and to deliver solutions to many challenges such as recycling, climate change, water scarcity, resource usage and energy recovery.

For more news, updates and information on the South African plastics industry, follow us on Facebook, Twitter, Instagram, YouTube, LinkedIn and Pinterest.