Sound absorption/Acoustuic attenuation coefficeint (α(ω)) of PVC foam?

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The discussion focuses on finding reliable sources for the frequency-dependent attenuation coefficient (α(ω)) of PVC foam, particularly at 220Hz. A referenced source provides data starting from 500Hz but lacks information for lower frequencies. Suggestions include conducting a Google search for sound absorption of foam at 220Hz, which may yield useful results. Additionally, it is noted that effective foam design should prioritize absorption starting at 125Hz and continue to improve through 500Hz. The quest for specific attenuation values for pure PVC foam remains a challenge.
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Homework Statement
What are some good sources providing the attenuation coefficient/sound absorption coefficient (properties) of PVC foam?
Relevant Equations
Power-law frequency-dependent acoustic attenuation:

P(x+Δx)=P(x)e ^(−α(ω)Δx); α(ω)=α0ω^(η)

Source: https://en.wikipedia.org/wiki/Acoustic_attenuation#Power-law%20frequency-dependent_acoustic_attenuation
I am currently doing a physics experiment to find the frequency-dependent attenuation coefficient (α(ω) )of pvc foam, are there any verified/reliable sources that show the attenuation coefficient α(ω) of pvc foam or materials in general?

Best I found is this: https://www.researchgate.net/figure...mer-as-a-function-of-thickness_fig6_258726695

The source above only shows the attenuation coeffcieint of pvc foam from 500Hz and above, but I'm investigating the attenuation coefficient at 220Hz. There are sources of attenuation coefficients for pvc composities on google, but not for pure pvc foam. Is there somewhere that I can find sample values? Thanks in advance!
 
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Welcome to PF. :smile:

I don't know if this helps, but I did a Google search on sound absorption of foam at 220Hz and got some good hits. Maybe have a look through the hit list to see if it gives you some ideas:

https://www.google.com/search?client=firefox-b-1-d&q=sound+absorption+of+foam+at+220Hz

What frequency does foam absorb?
It is better to design a foam technology that has more absorption above 125 Hz. and then transitions slowly up through and past 500 Hz. where every foam absorbs at 100%. This greater amount of absorption beginning at 125 Hz.
https://www.acousticfields.com/sound-absorborption/
 
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