A series of commercial seal layer grades ethylene vinyl acetate (EVA) resins were investigated in terms of thermal and rheological properties. The effect of vinyl acetate (VA) content in Differential scanning calorimetry (DSC) experiments revealed that the increase of VA content leads to decrease in melting point and heat of fusion. In oscillatory shear measurements the effect of long-chain branching on high shear sensitivity and long relaxation time of resins was revealed. In addition, a significant strain hardening behavior in extensional viscosity measurements was observed which indicated high melt strength of these resins.
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