If you have a treadmill which is made out of plastic, you have probably never really stopped to think about the journey that those materials have undergone to become your piece of exercise equipment. Plastics are durable and versatile materials that typically fall into two general categories: thermosets and thermoplastics.
Thermosets are generally more durable and stronger than thermoplastics, due in part to the thick molecular bonds introduced to thermoset resin during manufacturing. However, these bonds also cause thermosets to irreversibly cure, which means once a thermoset resin has been formed, it cannot be melted down and reformed.
On the other hand, thermoplastics are slightly less strong and less durable than thermosets, but can be metled and reformed following initial curing. Because of these inherent differences, plastics have varying life cycles, meaning their manufacturing, use, and disposal vary.
Some products of this material are destined for waste landfills, while others are suited for recycling and reuse. Older plastics were made from a wide range of natural products, including rubbers and gutta-percha.
Most today are made from processed petroleum. In fact, approximately sixteen percent of all petroleum is destined for use in manufacturing plastics, synthetic rubbers, and other materials-these include the ones used to construct your treadmill.
Manufacturing takes place in stages. First, petroleum is drilled from the ground and shipped to a refinery.
At the refinery, several different processes are applied to the crude petroleum, with different materials separated and treated so they can be used for material development, fuel, and many other different applications. When ethane and propane are extracted from the crude petroleum, they are then subjected to steam cracking.
Steam cracking is a process that breaks down these materials, which are saturated hydrocarbons, into smaller, unsaturated hydrocarbons. The ethane and propane are mixed with steam, which dilutes them, and then fed into an oxygen-free furnace.
The materials are heated very quickly at high temperatures around eight hundred and fifty degrees Celsius, which results in the cracking reaction. After cracking, the materials resulting are ethylene and propylene.
These materials are combined with catalysts, a type of material that causes a further petrochemical reaction. Often, the catalyst used for polymer manufacturing is called the Ziegler-Natta catalyst, a type of material of combined titanium compounds and organometallic aluminum compounds.
The introduction of the catalyst causes the ethylene or polythene to fluff into a type of powdered solution. Depending on the end plastic desired, various types of additives are added, which produce the final resin.
For thermosets, the resin is shipped to manufacturers who will form the resin into a finished shape and cure it. Thermoplastics, however, are extruded into a shape during production, and then shredded into small pellets called nurdles.
These nurdles are then transported to manufacturers, who can melt the nurdles down and eventually refashion them into something else. There are many types that are suited to different application needs.
Some of the more common ones are Polypropylene, used in packaging, ropes, food containers, and clothing, and Polystyrene, used in food containers, packaging foam, and jewel cases. Polyester is another that is more often seen in fibers and textiles.
Polyvinyl chloride is used in a wide variety of applications, including clothing and upholstery as well as plumbing and housing fixtures. Polycarbonate was designed to feature strong temperature and impact resistance, used often in engineering applications.
Last, Polyethylene is probably most familiar from its uses in shopping bags. Different kinds are destined for different ends following use.
Thermosets cannot be recycled, but various initiatives by different environmental and business groups are trying to repurpose and reuse thermosets so they don't simply end up in landfills. Thermoplastics can often be recycled, but there are different codes on all plastics as mandated by federal law.
Instead of hauling thermosets away to landfills, many projects are looking to put them to work after their initial application. Thermosets are also mixed into concrete laid for other purposes.
If a thermoset is determined to be safe to burn, many companies will burn used plastics for their furnaces. Other projects have repurposed plastics into playground equipment and filling for park areas.
Next time you hop on your treadmill, think about all that the materials have gone through to be formed to make your machine. It is a very interesting process, and a crucial invention in our world.
Author Resource:-
Ronald Pedactor has worked in the exercise and health industry for 31 years. When searching for a good deal on exercise equipment he suggests getting someone knowledgeable to treadmill reviews, and tell you their qualities.
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