Plastics in US autos surge
By Joseph Chang, Global Editor, ICIS Chemical Business
A small percentage increase in the overall weight of vehicles resulted in an outsized gain for plastics
The use of plastics and polymer composites in North American light vehicles surged 47 lb, or 13.2%, in 2020 to an average of 402 lb per vehicle, according to a new report by the Economics & Statistics Department of the American Chemistry Council (ACC).
A small percentage increase (1.9%) in the overall weight of vehicles of 77 lb, to an average of 4,040 lb resulted in an outsized percentage gain for plastics and composites.
Plastics and composites accounted for a record 9.9% of vehicle weight in 2020, a gain in share from 8.9% in 2019.
“Plastics and polymer composites are essential to a wide range of safety and performance breakthroughs in today’s cars, minivans, pickups, and SUVs,” said Kevin Swift, chief economist at the ACC.
“In fact, the use of plastic and polymer composites in light vehicles has increased from less than 20 lb per vehicle in 1960 to over 400 lb per car in 2020,” he added.
Plastics and composites used in vehicles has risen from 214 lb in 1990, to 281 lb in 2000, to 344 lb in 2010, to 402 lb in 2020.
“Today’s plastics typically make up 50% of the volume of a new light vehicle but less than 10% of its weight, which helps make cars lighter and more fuel efficient, resulting in lower greenhouse gas (GHG) emissions,” said Swift.
“Tough, modern plastics and polymer composites also help improve passenger safety, and automotive designers rely on the versatility of plastics and polymer composites and the aesthetic possibilities when designing today’s vehicles,” he added.
Major polymers used in light vehicles include on average 90 lb of polypropylene (PP), 74 lb of polyurethanes (PU), 50 lb of nylon, 29 lb of polyvinyl chloride (PVC), 25 lb of acrylonitrile-butadiene-styrene (ABS), 22 lb of polyethylene (PE) and 16 lb of polycarbonate, according to the ACC.
In addition to plastics and composites, North American light vehicles use an average of 243 lb of rubber, 49 lb of manufactured fibres (almost entirely synthetic fibres) and 33 lb of coatings on a dry weight basis, according to the ACC.
It is worth noting that PP is also used in thermoplastic polyolefin (TPO) elastomers, which the ACC reports separately under rubber. Average TPO use is about 40 lb per vehicle, so if this was included in plastics and polymer composites, the total would be the equivalent of over 440 lb per vehicle.
In 2020, with 12.99m light vehicles produced in North America, which includes the US, Mexico and Canada, this market represented around $42.2bn in chemistry. This shows steady growth from 11.9m vehicles produced in 2010 with associated chemistry valued at $36.8bn, the trade group noted.
Every light vehicle contains an average of $3,246 of chemistry (chemical products and chemical processing), up over 5% since 2010’s figure of $3,087. This includes antifreeze and other fluids, catalysts, plastic instrument panels and other components, rubber tyres and hoses, upholstery fibres, coatings and adhesives.
Plastics and polymer composites is the largest value component at $442, or 24.0% of the materials cost and 13.6% of the total chemistry value including chemical processing, according to the ACC.
“Today’s plastics typically make up 50% of the volume of a new light vehicle but less than 10% of its weight”
Composites are any combination of polymer matrix and fibrous reinforcement. Glass, carbon, aramid, and other fibres provide strength and stiffness while the polymer matrix or resin of polyester, polyurethane (PU), epoxy, polypropylene (PP), nylon, or other resin protects, and transfers loads between fibres, the report noted.
“This creates a material with attributes superior to polymer or fibre alone. In recent years, carbon fibre-reinforced composites have made inroads into light vehicle applications,” said Swift.
Plastics and polymer composites are used not only in automotive interiors, but in the exterior body – for example in bumpers and fascia (front) systems, lights, hoods and trim.
And as cars become more like computers with electronic connectivity features, more plastics are needed for housing sockets, switches, connectors, circuit boards, wiring and cable, and electronic and electrical devices, according to the ACC.
Plastics are also major components in automotive chassis, powertrains, fuel systems and engines, it noted.