Now rubber products are just as likely to be made artificially in chemical plants. That's largely because we can't produce enough natural rubber to meet all our needs. And that, in turn, is because rubber is so fantastically useful. Let's take a closer look at one of the world's most amazing materials!
By itself, unprocessed rubber is not all that useful. It tends to be brittle when cold and smelly and sticky when it warms up. Further processes are used to turn it into a much more versatile material. The first one is known as mastication (a word we typically use to describe how animals chew food). Masticating machines "chew up" raw rubber using mechanical rollers and presses to make it softer, easier to work, and more sticky. After the rubber has been masticated, extra chemical ingredients are mixed in to improve its properties (for example, to make it more hardwearing). Next, the rubber is squashed into shape by rollers (a process called calendering) or squeezed through specially shaped holes to make hollow tubes (a process known as extrusion). Finally, the rubber is vulcanized (cooked): sulphur is added and the rubber is heated to about 140°C (280°F) in an autoclave (a kind of industrial pressure cooker).
Although natural rubber and synthetic rubbers are similar in some ways, they're made by entirely different processes and chemically quite different.
An advantage natural rubber has over synthetic rubber is that natural rubber has higher tensile strength, higher tear resistance, and low odour compared to IR.