The right polymers and plastics can be keys to winning. For example, racing bicycles have to be both light and sturdy, a difficult combination to create. Manufacturers need to utilize carbon construction, with high-impact resins and high-strength fibers. The carbon layers and tube-shaped components need to be precisely tuned to the type of riding for which the bike will be used – racing, climbing or recreation. A deviation from the engineer’s specifications can result in disaster if the material cannot support tight cornering, tiring ascents, or screaming fast descents and breakaway sprints.
There’s no better example of the need for accurate materials than the Tour de France, a grueling 2,000+ mile bicycle race that runs in stages primarily through France and includes difficult climbs up the mountains and long sprints over breakaway areas. According to the official event website, the race is made up of 21 stages and includes 9 flat stages, 1 hilly stage, 9 mountain stages including 4 summit finishes (Andorre Arcalis, Mont Ventoux, Finhaut-Emosson et Saint-Gervais Mont Blanc), 2 individual time trial stages, and 2 rest days.
That course is punishing to the bicycles, which usually weigh less than 15 pounds (approx. 7 Kg). To produce a bike that light, attention must be paid to the materials used. Racing bicycles are usually made from carbon fiber/epoxy resin composites. To reduce the weight of the bike and design for performance and aerodynamics, over the past century the frames went from steel to aluminum to titanium to carbon fibers.
Fiber-Reinforced polymer composites are known as the light weight heavy hitters, but these materials must be accurately manufactured to specifications. The proper material make-up means reduced vibration of the joints, increased speed, the proper rigidity and high-level performance. As I mentioned, a variety of fibers is used as plastic composite material reinforcements and may be chemically modified to enhance their properties. Fourier Transformed Infrared Spectroscopy (FTIR) is a valuable polymer characterization tool for product design and manufacture. (To get some basics about Fourier Transform Infrared Spectroscopy, visit our FTIR Academy.)
Plastics-the mag, an online ‘magazine of plastics and innovation,’ published an article a couple years ago outlining the plastics used in Tour de France, and it covered more than just bicycles. Synthetic fibers have become indispensable in the design of clothing that is durable, elastic, permeable or impermeable and contains thermal properties. Polyesters, elastanes and other polyamides, as well as silicon-based polymers make clothing and gloves water repellent, breathable, and flexible. High-density foam reinforced with silicone make up more cushioning seats – which helps prevent pressure points which cause numbness and decreased blood circulation. Shoes have to be made of materials that combine lightness and rigidity. Polyamide wires replaced cotton shoelaces for uniform fastening. Sunglasses, which minimize glare, also need to protect the eyes from dust and insects.
And one of the most important pieces of equipment, besides the bicycle itself, is the helmet which is usually made from carbon, glass or polycarbonate fibers and protective polystyrene foam that absorbs shock. Do professionals need helmets? Ask the 20 riders who were involved in a massive crash during the third stage of last year’s Tour de France.
It’s obvious that advances in coating technology are contributing to the proliferation of improved high-performance, weather-proof fabric. So it is paramount that the chemistry is right for the fabrics used in the Tour de France, where the slightest inaccuracy can diminish performance.
Manufacturers must analyze the coatings before the product reaches the customer’s hands to ensure a particular fabric performs as expected for the application. X-ray photoelectron spectroscopy (XPS) is a quantifiable surface sensitive analytical technique that is particularly well-suited to investigating the surface treatment of polyester fabric. XPS, also known as ESCA (electron spectroscopy for chemical analysis) is ideal for determining the areas where an invisible surface modification, such as a fabric protection coating, has been applied, and also for finding the amount of coating present. It can also be used for quality control of invisible coatings on fabrics and other materials to determine whether they have been applied uniformly. (Read more about Using X-ray Photoelectron Spectroscopy to Investigate the Surface Treatment of Fabrics which discusses a simulation performed to simulate a production failure of treated fabric.)
Bike materials certainly have changed since the first Tour de France was held in 1903. The advancement in polymers and plastics has made the race faster and more competitive. But those polymers and plastic components have to be made precisely. Because you never want to cross the finish line and ask yourself, “What Went Wrong?”