Polyethylene Terephthalate (PET) Uses and Market Data
Polyethylene terephthalate (PET) exists both as an amorphous (transparent) and a semi-crystalline (opaque and white) thermoplastic, and can be made into either a resin, film or fibre. The semi-crystalline PET has good strength, ductility, stiffness and hardness while the amorphous PET has better ductility. PET also has good processability and can be recycled for other applications or returned to its constituent monomers.
The largest outlet for PET is for the production of synthetic fibres with bottle resin production the next largest application. In textile applications, PET is often referred to as ‘polyester’ while ‘PET’ is used often to refer to the packaging resins.
Polyester is the largest synthetic fibre used in the world with production split roughly 60/40 between polyester filament and polyester staple. Filament yarns are used in clothing, furnishings, tyre cord and technical textiles. Staple fibres are employed in knitted and woven textiles for clothing and furnishings such as bed sheets, bedspreads, curtains and draperies. Polyester fibrefill can be used to stuff pillows and cushion padding.
Polyester fabrics can have a synthetic feel when compared to fabrics made from natural materials. However, polyester does have the advantage of better wrinkle resistance and is often spun together with natural fibres such as cotton and wool to produce a fabric with blended properties.
PET packaging resin markets have seen very strong growth over the last 20 years. It first penetrated the carbonated soft drinks market because it is lightweight and strong. PET bottles are virtually unbreakable while a typical 1.5 litre bottle weighs about 40-45gm, about one-tenth the weight of glass.
PET has taken market share in the bottled water market due to its good clarity and not leaving any taste in the water. It has also found applications in more niche markets such as sports drinks and fruit juices, and is used to make bottles for cooking and salad oils, sauces and dressings.
The crystalline form of PET is used for trays containing pre-cooked meals that are reheated in either microwave or conventional ovens. Other uses for PET include thick-walled containers for cosmetic and personal care products as well as pharmaceuticals.
PET film is utilised in electrical applications such as dielectric metal foil capacitors and for packaging.