According to https://www.bbc.co.uk, the word tarpaulin is derived from tar and palling, the name for sheets to cover cargo on ships. Today, there are innumerable uses for tarpaulins commercially ranging from helping to secure items being transported to keeping valuable stuff protected from the elements. The materials from which the tarpaulins are made too differ with the applications as many of them are made for specific purposes. Typically, the most common materials for tarpaulins are canvas, polythene, and PVC. A quick look at their properties for a better understanding of their applications:
Even when untreated, canvas is a coarse material that breathes very well while offering a good degree of protection from the weather. Scientific advancements have enabled manufacturers to treat the material with different chemicals for better weather protection, resistance to UV rays, as well as water and mildew. Nowadays the most common use for canvas tarps is to cover moisture-sensitive goods used in the construction and agricultural sectors while being transported. The road transport sector prefers to use a large tarp of a variety known as Ripstop Canvas, which is essentially canvas blended with polyester. A special reinforced weaving technique gives it high strength to prevent tearing and an XLP treatment for making them water and rot-resistant. The end product is lighter in weight and less expensive.
Polythene tarpaulins are made from weaving strands of polythene, a lightweight and flexible material. They are ideal for a large variety of applications ranging from roofing, dome shelters, and road transport. Being waterproof, dirt repellant, and UV-resistant and available in a large variety of custom options, polythene tarps are appreciated for their versatility. Even though they permit easy handling because of the low weight, they are highly tear and abrasion-resistant as well as easy to repair. Used commonly in the construction and agricultural sectors, poly tarps typically come in high-density and low-density varieties. Compared to the low-density variety, the high-density tarp has a higher mesh count, extra coating of poly, and has a longer lifespan.
PVC tarpaulins, also known as vinyl tarps, are a combination of high-strength polyester material reinforced with PVC that yields a product with a smooth surface. While they are stronger and thicker than other tarp varieties, they are also extremely versatile and capable of delivering superior performance under challenging weather and chemical environments. Their high resistance to wind makes it ideal for transport covers, covers for hay bales, roof covers for industries as well as use as containment liners. Being waterproof makes them ideal for use in rainy or very cold conditions. When plasticizers are added, they become more flexible and resistant to cracking which is the most common form of degradation of poly tarps. Apart from being UV-resistant, they are also highly resistant to oils, greases, acids, and mildew while the addition of special chemicals can make them fire-retardant. It is easy to repair them onsite using hot-air welding/vulcanizing.
The selection of the tarpaulin type depends on what it will be used for, the duration of the use, and other performance parameters needed to be factored in. Tarps are available for all conceivable requirements, grades, and sizes to suit all budgets.