Humans have been using natural rubber for centuries.Columbus discovered on the voyage of the new world that a ball of native American play was made with a hardened plant SAP.Columbus and later explorers were all amazed at this bouncy ball.Some samples were taken back to Europe as curiosities.It was later discovered that the elastic ball could erase the marks of the pencil and gave it a common name, "rubber."This is still the name of the substance at the moment.This substance is rubber.
But it wasn't until 1839, when Charles Goodyear, an American, succeeded in vulcanization of natural rubber, that rubber became a useful material.The crosslinking of rubber chain is achieved by heating with sulfur, which makes the rubber have good elasticity.Why is rubber elastic?Let's analyze the molecular structure of rubber.The chain monomer of natural rubber molecule is isoprene.We know that the molecular force between the chain and the chain determines its physical properties.In rubber, the interaction between the molecules is weak, because it is not easy to interact with other chains.It's like two friends trying to shake hands, but everyone has a lot of things on their hands, so it's hard to shake hands.The force between rubber molecules determines the flexibility of the rubber.The molecules of rubber are easy to rotate and have ample space for movement, and the arrangement of molecules presents an irregular and random natural state.When subjected to external influences such as bending and elongation, the molecules are forced to show certain regularity.When the outside force is removed, the rubber molecules return to their original irregular state.This is why rubber is elastic.Because of the weak intermolecular force, the molecules can rotate freely, and there is not enough coupling between the molecular chains. Therefore, the molecules will slide between each other and the elastic will not show up.This slip is reduced by intermolecular entanglement.However, the intermolecular entanglement is unstable, and as the temperature increases or the winding of the time is loosened, it is necessary to establish a stronger connection between the molecular chains.This is the cure that Goodyear invented.The vulcanization process usually takes place at a temperature of 140 to 150 degrees Celsius.Goodyear's little stove was heating up.The main effect of vulcanization is simply to form a crosslink between the molecular chain and the molecular chain, thereby enhancing the interaction between the molecular chains.
to be continue...
But it wasn't until 1839, when Charles Goodyear, an American, succeeded in vulcanization of natural rubber, that rubber became a useful material.The crosslinking of rubber chain is achieved by heating with sulfur, which makes the rubber have good elasticity.Why is rubber elastic?Let's analyze the molecular structure of rubber.The chain monomer of natural rubber molecule is isoprene.We know that the molecular force between the chain and the chain determines its physical properties.In rubber, the interaction between the molecules is weak, because it is not easy to interact with other chains.It's like two friends trying to shake hands, but everyone has a lot of things on their hands, so it's hard to shake hands.The force between rubber molecules determines the flexibility of the rubber.The molecules of rubber are easy to rotate and have ample space for movement, and the arrangement of molecules presents an irregular and random natural state.When subjected to external influences such as bending and elongation, the molecules are forced to show certain regularity.When the outside force is removed, the rubber molecules return to their original irregular state.This is why rubber is elastic.Because of the weak intermolecular force, the molecules can rotate freely, and there is not enough coupling between the molecular chains. Therefore, the molecules will slide between each other and the elastic will not show up.This slip is reduced by intermolecular entanglement.However, the intermolecular entanglement is unstable, and as the temperature increases or the winding of the time is loosened, it is necessary to establish a stronger connection between the molecular chains.This is the cure that Goodyear invented.The vulcanization process usually takes place at a temperature of 140 to 150 degrees Celsius.Goodyear's little stove was heating up.The main effect of vulcanization is simply to form a crosslink between the molecular chain and the molecular chain, thereby enhancing the interaction between the molecular chains.
to be continue...
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