Is a latex balloon's maximum strain independent of thickness?

Click For Summary

Discussion Overview

The discussion centers on the relationship between the maximum strain of latex balloons and the thickness of the latex material. Participants explore whether the maximum strain is independent of thickness, particularly in the context of creating a custom balloon that can achieve a significant size difference between its deflated and inflated states.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • The original poster (OP) questions if the maximum strain of latex is independent of its thickness, suggesting that a thicker latex wall might not allow for the desired inflation without exceeding the maximum strain.
  • One participant discusses the kinematics of a spherical balloon, noting that achieving a significant increase in size (from 3" to 3') would require an isotropic stretch and raises the question of whether latex can sustain such a stretch while decreasing in thickness.
  • Another participant asserts that in a perfect world with defect-free film, thickness could be independent, but achieving high elongation (1200%) may be challenging. They mention that softening the cure system could increase elongation but might reduce tensile strength and elasticity.
  • There is a repeated comment about the age of the thread and the OP's absence from the forum, which does not contribute to the technical discussion.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between thickness and maximum strain, with some suggesting independence under ideal conditions while others highlight practical challenges. The discussion remains unresolved regarding the specific effects of thickness on maximum strain in latex balloons.

Contextual Notes

Participants mention the importance of defects in the material and the potential trade-offs involved in modifying the latex formulation, indicating that practical applications may vary significantly from theoretical assumptions.

morganj2003
Messages
1
Reaction score
0
Is latex balloon maximum strain independent of latex thickness?

I have been in search of a latex balloon that is relatively small when deflated and very large when fully inflated. Standard balloons that reach the desired inflated dimensions are much larger deflated than I would like. Specifically, I would like a balloon that can reach inflated radius of ~3'. Although, I want the balloon's deflated radius not to exceed 3".

Since I could not find an off-the-shelf balloon meeting the above requirement, I considered making my own balloon from latex. Perhaps if the latex was formed to create a balloon with ~3x the standard latex wall thickness, which would increase the maximum allowed internal pressure, I could meet my requirement. If the maximum strain of latex is independent of latex thickness, though, I don't think I will ever meet my requirement. A thicker balloon will require more pressure to stretch to a given dimension, but the maximum strain (stretch) before popping will remain unchanged. Is this true?

Maybe someone is aware of a material with much higher maximum strain than latex?

Thanks!
 
Physics news on Phys.org
The strains are determined by the kinematics. If you assume a spherical balloon, going from 3" to 3' requires an isotropic stretch of 12 x in each in-plane direction of the latex. So the total area increases by a factor of 144. This means that the of the latex decreases by a factor of 144. Is a sheet of latex capable of sustaining isotropic in-plane stretches of 12x in each direction while decreasing in thickness by 144x? That would have to be determined experimentally.
 
Thickness is independent in a perfect world (defect free film). To get 1200% elongation with this material is (to pardon the pun) a bit of a stretch. Softening the cure system will increase elongation but at the expense of tensile strength (and possibly elasticity). Removing defects is key - a double dip could help eliminate pinholes but a thicker film could increase the possibility of defects
 
nr8209 said:
Thickness is independent in a perfect world (defect free film). To get 1200% elongation with this material is (to pardon the pun) a bit of a stretch. Softening the cure system will increase elongation but at the expense of tensile strength (and possibly elasticity). Removing defects is key - a double dip could help eliminate pinholes but a thicker film could increase the possibility of defects
You realize that this thread is 2 years old, and that the OP hasn't been on Physics Forums since then?
 
Chestermiller said:
You realize that this thread is 2 years old, and that the OP hasn't been on Physics Forums since then?
No and no. I was looking something up and came across this thread so thought I would contribute
 

Similar threads

Undergrad How Does the Balloon Analogy Explain the Expansion of the Universe?
  • · Replies 5 ·
Replies
5
Views
2K
My balloon technology (the LDH honeycomb)
  • · Replies 6 ·
Replies
6
Views
3K
Graduate Estimating balloon internal pressure
  • · Replies 8 ·
Replies
8
Views
3K
How to calculate the time required to open a valve to inflate a balloon?
  • · Replies 2 ·
Replies
2
Views
2K
Undergrad Understanding Stress and Strain: The Relationship Between Two Variables
  • · Replies 9 ·
Replies
9
Views
2K
Compress helium in a CO2 cartridge
  • · Replies 10 ·
Replies
10
Views
3K
Calculating Pennies Suspended by Balloon as it Deflates
  • · Replies 1 ·
Replies
1
Views
4K
Graduate Gas in a semi permeable membrane - one for the gas experts
  • · Replies 4 ·
Replies
4
Views
2K
Mechanical modeling of inflating a elastomeric balloon
  • · Replies 6 ·
Replies
6
Views
2K
Modeling a kongming lantern (sky lantern)
  • · Replies 6 ·
Replies
6
Views
3K