How can I calculate the permittivity of soft and hard segment in polyurethanes?
It is possible to talk of permittivity of domains, not of segments...
You can mesure it if you have pure soft PU and pure hard PU...
Force Modulation AFM + sharp tip may show map of hardness changes. Below examples from my presentation.
There are some papers according to imaging hard and soft segments with AFM.
Mr Cavaille is right. Please read about the nanodomains of PU- then it would be better to understand phase separation in PU and influence of it on PU properties. One of my paper may be can help you, co-uthor Vancso. Moreover everything depends on ypur PU system: % of HS content, crosslinking, chemistry and so on...
Kind regards
Helena Janik
Dear all,
I agree with Mr Cavaille and Mrs Janik; in addition, the phase separation in the polymer could be a key factor in the permettivity of the material.
If you want to calculate, or better, to predict, the permittivity that a monomer that you will use in the synthesis of the PU can give to the complete material, maybe computational calculations could be useful.
I hope it was helpful.
Best regards.
Modeling exercises have been undertaken to estimate the value of the permittivity of a polymer from the structure of the monomer and its dipole moment. These models have had very little success. The only way to estimate the dielectric constant of a polymer, safely, is to measure it.
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