OEMs including Mercedes, Ford, Toyota, Tesla and Chrysler have been named as using jute for their car parts, said SupplierBusiness, pointing out a major advantage—the "lack of volatility compared to petroleum-based materials. This has pushed plastic and polymer makers to shift from traditional petroleum products to alternative sources such as biobased materials."
Another advantage to some biobased materials is biodegradability, converting into "water, carbon dioxide, biomass and possibly methane" as they degrade. While this would appear to be an advantage for automakers "looking to hit total emissions targets," the degree of biodegradability "strongly depends on the structure of the polymer," SupplierBusiness stated.
For instance, SupplierBusiness noted that polyethylene derived from sugar [cane] is not biodegradable. However, in researching this, PlasticsToday found that it is recyclable, because it has "the same physical and chemical properties as regular plastic—the most common type is known technically as PET—and maintains full recycling capabilities," according to sugarcane.org.
SupplierBusiness noted that polyhydroxyalkanoates (PHAs) are not biodegradable. However, PlasticsToday found information that "the microbial polyesters known as polyhydroxyalkanoates positively impact global climate change scenarios by reducing the amount of non-degradable plastic used. PHAs can be produced from renewable raw materials [and] are degraded naturally by micro organisms that enable carbon dioxide and organic compounding in the eco system, providing a buffer to climate change." (See Elsevier's Journal of Bioscience & Bioengineering, Vol. 110, Issue 6, 2010, "Current Trends in Biodegradable Polyhydroxyalkanoates," by Suchada Chanprateep.)
In the search for weight savings in automotive production, some unorthodox materials have been tested, such as a "natural rubber derived from dandelion . . . for vibration and mounting elements in vehicles," said SupplierBusiness. Additionally, Ford is working with Heinz on the possibility of using "tomato fibers to develop composite materials for car parts." Ford also "previously used kenaf, a tropical plant related to cotton and okra plants, to replace oil-based materials in the manufacturing of doors for its Escape model."
Using plants as the base material for automotive components begs the question of whether these biobased materials have the "durability and resistance to heat," said SupplierBusiness. Of course, the editorial notes, "there remains a great deal of potential, as developments in plastics and composites start to replace metal. For instance, Mitsubishi Chemical has developed a new grade of biobased engineering plastic, Durabio, that offers higher resistance to impact, heat and weather than conventional engineering plastics and can be used for automotive housings."
Contitech has made headway in products made from non-traditional materials, as well, noted SupplierBusiness, such as the company's new rear-axle transmission crossbeam, which is made from fiberglass-reinforced (FRP) Ultramid polyamide produced by BASF. "The use of new material reduces the weight of the rear-axle transmission crossbeam by a significant 30% compared with one made from die-cast aluminum," said SupplierBusiness.