what is used by polymers?

A range of polymers are used for the construction of catheters, including silicone rubber, nitinol, nylon, polyurethane, and polyethylene terephthalate (PETE) latex, and thermoplastic elastomers. Silicone is one of the most common choices because it is inert and unreactive to body fluids and a range of medical fluids with which it might come into contact. On the other hand, the polymer is weak mechanically, and a number of serious fractures have occurred in catheters[citation needed]. For example, silicone is used in Foley catheters where fractures have been reported, often requiring surgery to remove the tip left in the bladder.

There are many different types of catheters for bladder problems. A typical modern intermittent catheter is made from polyurethane and comes in different lengths and sizes for men, women and children. The most advanced catheters have a thin hydrophilic surface coating. When immersed in water this coating swells to a smooth, slippery film making the catheter safer and more comfortable to insert. Some catheters are packed in a sterile saline solution.

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