Multiple layers of materials are used to make motorcycle helmets. A rigid outer shell conceals a layer of Styrofoam padding. It is also covered with an impact-absorbing Styrofoam linedr. As the foam and padding layers within helmets are often more similar than diverse, this article will highlight the most popular materials.
How helmet protect your head?
The helmet’s hard outer shell was designed to distribute the impact force across a larger portion of the helmet. Once the helmet shell has been hit by the impact, the Styrofoam in its interior will collapse. This type of foam is also known as Expanded Polystyrene Foam (EPS) – a stiff, yet easily crushable foam.
Experts advise that you should wear any helmet. We couldn’t be more agreeable. It’s worth noting, however, that helmet design technology has advanced sufficiently to ensure that even higher-end helmets provide more protection than they did in the past.
Other than the extras like Bluetooth communications built-in, advanced helmets differ from basic ones mainly because of their shell material. While inner Styrofoam could be stacked or layered differently than the outer shell material, that’s what makes the difference.
There are two basic types of plastic materials for helmet construction: thermoplastics (or thermoset) .Materials in the “thermoplastics” group are made up of simpler oil-based plastics. These plastic mixes do not require a chemical reaction to cure them. All they need is to be heated up into liquid form then poured into a mold with a helmet shape to cool and harden.
Thermoplastics can be easily melted down and reshaped once again without the use of chemical decomposition.
Other plastic helmets called “advanced temperature set resins” or ATRs require the addition of curing agents to achieve the chemical reaction needed for the plastics to harden.
All of these plastics provide a good mix of rigidity & flexibility but they are less durable than composite weave materials. For safety reasons, all plastic helmets must be thicker. Adding extra material to them makes them heavier and heavier. Their advantage is however their lower cost.
There are many types to choose from when it comes to thermoplastics.
ABS (Acrylonitrile Butadiene Styrene)
ABS plastic can be described as a thermoplastic that blends the strength and rigidity of a number of polymers with the ruggedness of polybutadiene. ABS plastic is used extensively in helmets. It’s chemical-, heat- and dents-resistant and has good protection. ABS plastic is heavier and cheaper than woven thermoplastics.
Polycarbonate & Lexan
Polycarbonate is a thermoplastic that is made from a synthetic poly resin and contains a carbonate-rich chemical composition. Polycarbonate, by itself, is a clear resin that is used as the primary component in helmet visors, greenhouse windows, eyeglass lenses, and medical optics.
General Electric has trademarked its polycarbonate formulation and markets it as Lexan. Sometimes you will see checkboxes to purchase helmets made of Lexan.
Polycarbonate mixtures offer better impact resistance than ABS, so if you don’t mind the extra weight, this is a good option.
Advanced Thermoset Rein (ATR),
The only difference between thermoplastics is the way they harden and cure. Thermoplastics can cure and harden naturally (without the need to add curing agents) when they cool.
A curing agent, usually an epoxy or polyurethane (or other ingredients), must be added to thermosets in order to cause a chemical reaction that allows the plastic to harden. After adding the epoxy, the mix can be heated and forced into an injection mold.
Once the chemical reaction completes and the helmet shell sets, it’s final. It can’t be melted down again and reformed as thermoplastics. Thermosets can be considered one of the tougher types.
While it’s obvious that you should get the best helmet for your budget, not all people can afford the best. And if you are residing in Australia search Shoei Helmets Australia.