Plastic is essential to the design and production of vehicles, making them lighter and more fuel-efficient. Scientists and specialists at Volkswagen of America’s polymer laboratory in Chattanooga, Tennessee share why polymers are the backbone of today’s automotive industry.
“Polymers have improved all of our lives in many ways, but especially in vehicles,” said Ellen Collins, a laboratory evaluation specialist who has studied the evolution of these advanced materials for the past decade.
A polymer is a long molecular chain made up of bonded chemical units or monomers. These chemical chains are strong, resistant and have a high tolerance for heat.
“Unlike metals, you can directly mold them, which can make them more versatile and less expensive for the manufacturer. And because they can be made quickly, they can go into production much faster than other materials, which can also help reduce the cost for the end-user,” Collins said.
The automotive industry is the third largest consumer of polymers after packaging and construction. On average, about 39 different types of basic plastics are used in a car and more than 70% of the plastic is derived from four main polymers: polypropylene, polyurethane, polyamides and PVC. These polymers can be found throughout the vehicle, from a car’s tires to its trunk.
Collins and her team at Volkswagen test, inspect and approve these components, looking at texture, mold and grain. They work with the company’s chemical compound suppliers to supply the correct materials.
“Look at the evolution of the instrument panel. Originally, the dashboard was made of wood or metal. But, when they changed it to polymers, it started being referred to as a crash pad. Why? Because it is softer and had protective padding, which can lessen the impact on the driver during an accident,” said Collins.
One of the main objectives of Volkswagen’s polymer laboratory is to help reduce the overall weight of a vehicle as much as possible without losing any capabilities.
According to the Department of Energy, reducing a vehicle’s weight by 10% can result in a 6-8% improvement in overall fuel economy. It boils down to physics: The lighter the vehicle is, the less power is required to get it moving and the less energy it needs to keep it moving at a constant speed — thus saving fuel.
Volkswagen’s lab recently helped suppliers produce a lightweight polypropylene that is incorporated into the door frame of the Volkswagen Atlas.
As demand for electric and hybrid vehicles increases, so too will the demand for polymers. “We have to incorporate lighter parts to help offset the weight of the car’s heavy (lithium) batteries,” Collins said. “We believe that polymers are the future…and hope that all car companies are taking the same approach because the sooner they bring down the weight of their vehicles, the quicker we can work toward reducing our carbon footprint.”
By 2025, Volkswagen is committed to reducing the carbon footprint of its global fleet by 30% compared to 2015 and aims to make Volkswagen Group’s balance sheet CO2 neutral globally by 2050.
The Volkswagen polymer lab is located near its Tennessee manufacturing plant, which produces the Atlas SUV and Passat sedan. The plant, currently undergoing an expansion, will begin producing the all-electric ID.4 and ID Buzz in 2022.