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Natural rubber is a polyisoprene as a main component in natural polymers, molecular formula (C5H8) n, which composition is 91% - 94% hydrocarbon rubber (polyisoprene), as the rest of the protein, fatty acids, ash, sugar and other non-rubber material according to the resin main chain composed of classification can be divided into carbon-chain polymer resins, polymers and miscellaneous elements of an organic polymer chain carbon chain polymer main chain refers to the whole of carbon atoms polymers, such as polyethylene, polystyrene and the like. heterochain polymer refers to a polymer backbone consisting of carbon and oxygen atoms, nitrogen, sulfur and other elements composed of two or more, such as polyoxymethylene, polyamide, polysulfone, polyether, etc. element refers to an organic polymer main chain does not necessarily contain carbon atoms, mainly composed of atoms of silicon, oxygen, aluminum, titanium, boron, sulfur, phosphorus and other elements, such as silicone seen rubber are mainly composed of natural polymers, polymers, carbon dioxide will be produced by combustion, SO2, some will have N2 or NOx and the like.
However, the rubber band in the water will not let these harmful substances evaporate.