Commodity Plastics – The ‘Almost’ Everywhere Versatile Thermoplastics

Last update on Aug 24, 2022

Plastics are everywhere! Their versatility and the adjustable properties make them a material of choice in plenty of applications. The most common type of plastics you can even find on your desk right now or kitchen are commodity plastics. Unlike engineering plastics which are popular in all sorts of high-end applications, they show less exceptional mechanical properties. That is why they are not very expensive too and can be easily processed into items of daily use.

MarketsandMarkets1 anticipates that global commodity plastics market size will grow from USD 468.3 billion in 2020 to USD 596.1 billion by 2025. One of the most demanding markets is the packaging industry which has picked up pace even during the pandemic when the demand for single use plastic packaging arose far more than usual.

Source: www.gteek.com/Engineering-Plastics

The most popular types of commodity plastics known today are polyethylene, polypropylene, polystyrene, polyvinyl chloride, and polyethylene terephthalate.

Here are the most common properties associated with the following polymers.

#1 Polyethylene

The monomer ethylene (C₂H₄)_n units link to form the polymer polyethylene (or polythene/PE). It is the most used type of thermoplastic with applications such as bottles, food packaging, bubble packaging, industrial liners, and mattress bags. It is projected that the market will be valued at USD 135.87 billion by 2030². It is becoming a highly cost-effective solution owing to recent developments that may replace some costlier alternatives. The most common types of PE are low density (LDPE), medium-density (MDPE), and high-density (HDPE).

LDPE has a high level of short and long sidechain branching which results in low density and crystallinity while greater flexibility and toughness than HDPE. HDPE is known to exhibit resistance to UV and chemicals. Due to difference in their properties, LDPE is more popular for packaging films and mulch in agriculture.

Read this detailed guide on Polyethylene >>

#2 Polypropylene

Polypropylene (PP) is another type of thermoplastic that is produced from the monomer propylene. It shows similar characteristics to PE but is harder and more resistant to heat. PE and PP together belong to the family of polyolefins. It is a lightweight, durable polymer with good tensile strength (0.95--1.30 N/mm²). The global market for polypropylene³ is projected to grow from USD 76.00 billion in 2021 to USD 108.57 billion in 2028.

Polypropylene can be processed by multiple processing methods: extrusion, blow molding, injection molding, and general-purpose extrusion. It is available as three types: homopolymer, copolymer, and impact copolymer. PP Homopolymer contains propylene monomer in a semicrystalline solid form. The copolymer type is further divided into random copolymers and block copolymers produced by polymerizing of propene and ethane. Propylene homopolymer containing a co-mixed Propylene Random Copolymer phase which has an ethylene content of 45--65%, is referred to as PP impact copolymer.

Polypropylene finds great use in packaging, textiles, healthcare, pipes, automotive and electrical applications.

Check out 14000+ commercial polypropylene grades in our database >>

#3 Polystyrene

Polystyrene (PS) is another cost-effective, widely produced, and used plastic. It is made from the aromatic hydrocarbon styrene. It occurs transparently naturally, but with the use of colorants and other additives, it is used in electronics, appliances, gardening pots, toys, and many other common applications. When copolymerized or blended with other polymers, it is known to provide hardness and rigidity to a many other polymers and rubbers.

While the solid form is hard and brittle, polystyrene is also available as foam [expanded polystyrene (EPS) or extruded polystyrene (XPS)]. This lightweight foam finds use in protective packaging, home and appliance insulation, and disposable eating utensils. Although polystyrene is resistant to many acids and bases, it can be easily dissolved down in contact with organic solvents such as acetone. Polystyrene is generally considered to be non-biodegradable. However, some recent research has been revealed that a common super worm can 'eat' polystyrene.

Check out over 1700+ commercial PS grades in our database >>

#4 Polyvinyl Chloride

Polyvinyl chloride (PVC) is yet another low-cost polymer exhibiting numerous properties for common applications. It is made by the polymerization of the monomer vinyl chloride.

According to a recent report⁴, its capacity will register a growth of 16%, increasing from 60.27 mtpa in 2021 to 69.73 mtpa in 2026. PVC is available in two forms: rigid or unplasticized (RPVC or uPVC) and, secondly, as flexible.

Apart from its low price, PVC is popular for its resistance to environmental degradation, resistance to chemicals, hardness & tensile strength (rigid PVC).

While the rigid form can be used in pipes, profile applications such as doors and windows, with the use of plasticizers (most popular being phthalates), it can be used in electrical cable insulation, plumbing, flooring where it replaces rubber.

Check out 8000+ commercial PVC grades in our database >>>

#5 Polyethylene Terephthalate

Polyethylene terephthalate (PET) is a naturally transparent and semi-crystalline plastic. It belongs to the family of polyesters. PET is product of the polymerization of ethylene glycol and terephthalic acid. Amongst its properties, stiffness and hardness, good strength, ductility is most prominent. PET is the most widely recycled plastic. Since it is inert, it resists attack by micro-organisms and can be commercially recycled by chemically breaking it down to its component materials to make new PET resin.

Bags and Bottles Made of Polyethylene Terephthalate

PET is used in bottles, bags, containers, packaging films, carpets, microwave containers. It can be processed through vacuum forming, injection molding, compression molding and blow molding. Due to its high strength & lightweight, it is energy efficient and allows for more product to be delivered in less packaging and using less fuel for transport.

Check out 700+ commercial PET grades in our database >>

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