CW Blog

Applications of natural fiber composites (NFC) can be traced back to the ancient Egyptians, who used to make bricks out of clay mud and straw. More recently, the use of natural fibers as a reinforcement in polymer composites has been gaining a lot of attention, especially in the research community, and there are numerous review articles published on the applications of NFCs. However, to date the commercial use of NFCs is limited to wood plastic composites and automotive inner door panels. Moreover, few clear statistics on the current market for NFCs are available, and in fact most reports I’ve come across discuss the envisioned potential markets rather than the current market.

The world consumption of natural (also known as “vegetable” fibers since they are derived from plants such as hemp and flax) fibers that can be used as a reinforcement for composites totaled $4.3 billion in 2018, with a compound annual growth rate (CAGR) of 3.3% from 2010-2018. This low growth rate is a strong indicator that the market is not growing as quickly as anticipated, and raises a valid concern: What’s holding NFCs back? In other words, what are the barriers to the adoption of NFCs in the numerous applications of composite materials? To answer this question, one should refer to the diffusion of innovation theory developed by scholar E. M. Rogers, which explains how new ideas, technologies and products spread among participants in a social system.

Wood is revered for a reason — it is used for creating warm, inviting home environments, furniture, art and more. Remember the wooden rollercoasters of old? Despite its sentimental value, wood can’t make it in most harsh industrial environments, says Eric Kidd at Bedford Reinforced Plastics (Bedford, Pa., U.S.): “When exposed to moisture or water, wood is susceptible to warping, rot, mold and mildew. And when in a seaside or coastal location, the moisture, in addition to higher winds and salt spray, creates an especially corrosive environment that can cause a wood structure to break down more quickly over time.” Unlike wood, fiber-reinforced polymer (FRP) is unaffected by salt spray, moisture or prolonged immersion in water, making it a good material choice for piers, pilings, pedestrian bridges, cooling towers and other structural applications in harsh environments.

Insects, including termites, marine borers and carpenter ants, also pose a threat to wood structures. They eat away at the wood, affecting the integrity of the structure. To fight pests, wooden structures are often treated with hazardous preservatives or coatings, which are environmentally harmful. In contrast, FRP does not require any coatings or preservatives to withstand the effects of corrosion, rot or insects, and it has little environmental impact. And, dimensional stability in extreme weather conditions along with flexural strength make a strong case for FRP’s application in geographic areas that experience harsh temperature extremes.

Three recent graduates of Karlsruhe Institute of Technology (KIT, Karlsruhe, Germany) have launched a “virtual composites solutions” company called Simutence GmbH (also in Karlsruhe) to offer design and engineering services, including custom simulation methods that plug into popular simulation tools. Customers in the automotive, aerospace and sporting goods/recreational fields are the primary targets.

The company was co-founded by Dr.-Ing. Martin Hohberg (who specializes in filling simulation for discontinuous-fiber-reinforced thermoplastics and thermosets, particularly locally reinforced, compression-molded sheet molding compound); Dr.-Ing. Benedikt Fengler (who specializes in topology and layup optimization, and leads group efforts in the use of locally continuous reinforcement in otherwise discontinuous fiber composites); and Dominik Dörr (a doctoral candidate with a specialization in draping simulation, especially unidirectional thermoplastic tapes, and who leads group efforts in continuous fiber composites). The trio met during their doctoral studies at KIT, where they also participated in a consortium focusing on transportation lightweighting solutions, including composites. Additionally, they worked on Project SMiLE (System integrative Multi-material Lightweight construction for Electromobility) sponsored by the German government (see “Hybrid thermoplastics give load floor impact strength”).

As innovative as the CarbonPro pickup box is (see more about its design and development in “Chopped carbon fiber, polyamide and innovation redefine the modern pickup truck bed”), it’s certainly not the only game-changing feature on the GMC Sierra Denali pickups from General Motors Co. (Detroit, Mich. U.S.). While it shares aluminum doors, hood and standard tailgate with “sister” Chevrolet Silverado models, visually the GMC models differ from Chevrolet counterparts through the use of asymmetrically-shaped wheel arches, distinctive sickle-shaped LED running lights, a “fanged” front grille and a more luxurious (but still durable) interior featuring leather-appointed seating with contrast stitching, and trim using real wood and aluminum accents.

Both models are taller than their predecessors, with wider beds, more cargo space (1.8 cubic meters), an extra 7.5 centimeters of rear-seat legroom and rear seats that fold forward to reveal hidden storage space. High-end trim levels for both 2019 Silverado and Sierra pickups are powered by a 3-liter/6-cylinder diesel engine or a 5.3- or 6.2-liter V8 gasoline engine. The gasoline engines feature Dynamic Fuel Management, a feature allowing between one and seven cylinders to be shut off to boost fuel economy while the vehicle is running. The diesel and 6.2-liter gasoline engines are mated to 10-speed automatic transmissions developed in partnership with Ford Motor Co. (Dearborn, Mich., U.S.). Blind-spot warning systems, pedestrian detection and automatic braking at low speeds are additional safety features common to Silverado and Sierra platforms. However, a host of additional safety and convenience features are where the two platforms really start to diverge.