I wonder if We need a better adhesion in polymer, we need polymers with high crystallinity? And If we need wider heat sealing windows, we need high amorphous? My understanding is correct? Thank you for your response.
Adhesion is based on van der Waals (dispersion) forces. You need good, intimate contact between the adhesive and the substrate. Amorphous materials are better in general, as the are more deformable than crystalline materials. Crystalline materials are stuck in their geometric matrix, making it more difficult to achieve the close contact that is needed. Having said that, crystallinity can be very helpful in absorbing stresses applied to the adhesive and also in increasing the working temperature.
In summary, if you understand the physics of adhesion, you can use both amorphous and crystalline characteristics to you advantage.
John Aspen Research, -
"Turning Questions into Answers"
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