Why do some balloons burst as soon as they are pierced, while others do not burst even if they are penetrated?

The surface area of ??a fully inflated rubber balloon is more than ten times larger than that of an uninflated rubber balloon. It can be seen that the expansion and contraction force of the balloon is quite large. As long as we prick the fully inflated balloon with a needle, the balloon will explode instantly. If you put a small piece of tape on a fully inflated balloon and then prick the tape with a needle, although the air will leak, it will not shrink because the tape is not as stretchable as the balloon.

Therefore, the balloon will not explode at this time. Rubber is very stretchy, and balloons made of rubber can be blown up very big. A fully inflated balloon will become very thin, only a few tenths of its thickness when not inflated. Such a thin ball skin will be squeezed if you apply a little force. When we blow up a balloon, we often blow it too hard and burst it. If you prick such a thin ball with a needle, it will of course explode. What factors influence the way a balloon bursts? In order to figure this out, the researchers designed an experimental device and conducted experiments with latex films of different thicknesses. After blowing air, the membrane inflates to form a "balloon" that is eventually punctured by the spikes on the device. The entire process will be clearly recorded by high-speed cameras, and the researchers will also measure the tension of the balloon membrane.

The results showed that what affected the way the balloon ruptured was the tension of the balloon membrane and the initial thickness of the membrane. When the tension reaches a critical value, the original cracking along a crack will become branched cracking, forming more fragments. The researchers found that the cracking speed will increase with the tension, and finally reach a limit speed value at the critical time. Above this critical value, the cracking speed cannot continue to rise when the tension continues to increase, and at this time, multiple cracks will form. Energy is released in the form of branching cracks.