Why are balloons harder to inflate when you start, and feel easier once they start expanding?

Question

I mean your average party balloon, when it’s completely deflated, it seems you have to put extra effort into getting it going. As soon as it starts inflating, you need less effort.

In: Physics

Answer 1

[There is no ELI5](https://www.sciencedirect.com/science/article/abs/pii/S0020746214001292)

Rubber has complex mechanical properties when it’s stretched, which cause the effect described by OP.

PDF of the paper whose abstract I linked to above is available on arxiv.org.