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How much difference between internal and external pressure can a balloon withstand?

how would the value be calculated?

I found an equation:

http://library.thinkquest.org/C003758/Function/laplacelaw.htm

But, how does that relate to a material?

user2218665
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1 Answers1

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For a spherical balloon (which is a reasonable model to start with) the tension in the material is $\sigma = 0.5 P R /\delta$ where P is the pressure difference between inside and outside, R is the radius, $\delta$ is the thickness. The material will break at some critical value of the tension which is called the tensile strength of the material. For example, for rubber the tensile strength is $\sigma_c$=15e6 Pa $\approx$150 atm, so a rubber balloon with R=1 and $\delta$=1 mm (in the inflated state) can withstand the excess inside pressure $P=2 \sigma_c \delta/R$=0.3 atm. See more info and numerical values of the tensile strength for some common construction materials on http://en.wikipedia.org/wiki/Tensile_strength.

Maxim Umansky
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