Rubber bands can shrink back after being stretched, which is the function of rubber molecules. Rubber molecules love to move, they are arranged hand in hand, because each molecule is always in active motion, so their team is always crooked and messy. If you pull the rubber band hard, the rubber molecules will lose the "freedom" to move arbitrarily, and the team they are arranged in will be neat and Tidy, e a aparência será esticada ., no entanto, essas moléculas de borracha não estão dispostas a ficar solitárias, elas querem restaurar sua "liberdade", para que gerarão uma força para restaurar o estado original, que é a elástica de borracha .}}
If it is stretched to a certain extent, the molecules will "slip" and can no longer return to their original state. In order to prevent the "slip" phenomenon between rubber molecules, the rubber molecules must be connected to each other to form a three-dimensional network. This method is called cross-linking, which is as elastic as a mesh door made of iron Barras . Em 1839, a borracha vulcanizada da Goodyear descobriu, que usa o enxofre como um agente de reticulação para fazer as moléculas de borracha na borracha crua mantêm vários lugares, transformando-o em uma borracha elástica de alto desempenho e elástico.
Os elásticos de hoje são feitos desta borracha elástica .
