If you roll up a piece of paper and leave it for years it will stay rolled up. If you leave it rolled up for a minute it is easy to unroll. Of course this must be because the energy stored in that paper when it was first rolled was released in a way other than unravelling. So my question is how does a paper lose its EPE?
paper is subject to creep: when an external load is applied, the resulting internal stresses relax slowly over time and the paper takes a set, meaning its original shape is deformed. The set persists even when the external load is removed.
That deformation happens because under steady stress, the paper fibers slowly slip past one another and the deformation stresses diminish in response.