There are numerous heat shrink tubes on the market, with sizes, colours, and materials to suit all purposes. When buying heat shrink tubes, you should carefully consider the purpose of the tubing, as well as the equipment you have at your disposal.
Heat shrink tubes can be made of several different materials. Each material has different properties. Some shrink more easily than others, some are more resistant to chemicals, some are more flexible, and some are designed for use at extreme temperatures.
For consumer grade applications, polyolefin heat shrink tubing is the most popular variety. These heat shrink tubes are available in a range of diameters, and with several different shrink ratios, so it is easy to find one that will fit the wires or components that you wish to protect.
Polyolefin heat shrink tubing is fairly inexpensive, and can be purchased from several online stores, or from the Maplin or RS Components catalogues. Specialist versions of polyolefin heat shrink tubing are available for case modders, car enthusiasts, and other hobbyists. These special heat shrink tubes are designed to be easy to use, and will shrink under gentle heat, rather than requiring a hot air gun or some other expensive equipment.
Polyolefin heat shrink tubing is suitable for most uses, and has a continuous operating temperature range of between -55 °C and + 135 °C. This means that it can be used outdoors, and in most normal appliances. There are adhesive lined heat shrink tubes available for appliances where a very tight seal is required.
For appliances where aesthetics are important, PVC is a good alternative to Polyolefin. PVC tubes are less heat tolerant, however clear PVC heat shrink tubes are more transparent than clear Polyolefin tubes, and the coloured versions of the tubes are glossier, more scratch-resistant, and less prone to losing their colour over time.
Where extreme heat tolerance or chemical resistance is required, heat shrink tubes made of a fluoropolymer should be used. There are many different fluoropolymers. The most durable is PTFE, however this has a very high shrink temperature, and can be quite expensive.
Cheaper alternatives include Fluorinated ethylene propylene (FEP), and Polyvinyliden fluoride (PVDF).
Neoprene is often used where flexibility is important, and silicone rubber heat shrink tubes are a popular choice where the wires or components that are being protected are likely to be subjected to a lot of friction, scraping and other abuse.