Melting Temperature or Softening Point

The Vicat method measures the temperature at which an arbitrary determination or a specified needle penetration (Vicat) occurs when polymers are subjected to a standardised set of testing conditions. This property can also be measured by using TMA [plots of temperature versus compression (mm)]. 

Tang and co-workers [10] found that the Vicat softening temperature (Ts) of ABS-calcium carbonate composites increased with the addition of filler which indicated the beneficial effect of the filler on the heat resistance of the terpolymer. 

A ring apparatus has been used to determine a suitable temperature range for the extrusion of LDPE/HDPE, LDPE/PP, HDPE/PP blends [11] and PPS-acrylonitrile-butadiene blends. 

The true melting points of crystalline polymers can be determined by plotting the differential scanning calorimetry (DSC) melting peak temperatures as a function of the square root of heating rate and linear extrapolations to zero heating rate. 

Differential thermal analysis (DTA) has been used to study the effect of side-chain lengthin polymers on the melting point and the effect of heating rate of polymers on their melting point. DSC has been used to evaluate multiple peaks in polymers [12, 13]. DSC has also been used to study the heat changes occurring in a polymer as it is cooled (plots of temperatures versus heat flow). 

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