ASU News Rubber

The first generation inflatable boats were manufactured from fabric that are proofed or made airtight by the application of thin layers of vulcanized rubber. The fabric used back then was commonly cotton but silk was also an option especially in airships. When ultra light material for inflatable was needed for boats, then silk was used as the preferred material. The first manufacturers of inflatable boats were pull companies like Goodyear. It was customary to build inflatable life rafts back then where a rubber bladder that resembles to pull s inner tubing is wrapped in a protective case of heavy canvas. The use of natural rubber and cotton fabric as materials for inflatable boats is acceptable but, these materials have major flaws. Natural rubber is naturally soft. When rubber is combined with sulfur (vulcanize) to make it stronger and harder, it still retains its elasticity.

However, the more rubber is vulcanized the more it loses its flexibility. A rubber boat needs to be tough yet flexible and in this case to compromise is the only option. A boat made of rubber-impregnated fabric is not as tough or as flexible as wanted. A boat made from vulcanized rubber loses its protective coat every time the fabric is folded. When improperly stowed, the rubber material fuses where they touch which leads to further lost of its protective coating. Natural rubber degrees under the hot sun and is easily oxidized by the ozone making it a susceptible to major damages when exposed to the elements for even a few hours. Natural rubber and cotton fabric boats were the only options then. Currently, these materials are obsolete and no one uses them for manufacturing inflatable boats.

Today s choices in inflatable boat accessories are: neoprene, Hypalon and a form of PVC. Neoprene and Hypalon are man-made rubber that are often used together in the manufacture of inflatable boats. PVY or polyvinyl chloride is plastic. There are marked differences between artificial rubber and plastic. These differences need to be examined and considered when choosing an inflatable boat.