Change in length of rubber band on cooling

Some where i read that on cooling of rubber band it expands where as when heated it contracts . Why does it happen?Full description.please

 

Asked Bipin Kumar

Answer

The rubber band actually expands when it gets colder. This occurs because of the unusual polymer structure of rubber. When the long chains get hotter and vibrate, they actually shorten, causing the material to contract. When the chains cool down, they relax and stretch out, causing the material to expand.

 

Please refer to https://www.scientificamerican.com/article/stretch-it-how-does-temperature-affect-a-rubber-band/ for more details

.http://www.physlink.com/education/askexperts/ae478.cfm is also a good reference

Also visit https://en.wikipedia.org/wiki/Rubber_elasticity