Determination of xylene-soluble fraction of polypropylene

General Notes

Polypropylene (PP) is a synthetic polymer widely used as raw material in many industries. As for most of other polymeric substances, the reactivity of PP is in the direct dependence on accessibility of its free surfaces and volumes, i.e. it grows up with the increase of amorphous content. The chemical reaction and modification ability of PP is being attributed to estimation of the xylene-soluble fraction (XS).

Measurement Flow

For this method it is needed the Spin Track NMR analyzer together with the XS application and the tempering device. Sample preparation consists of filling tube and tempering at 40 °C for 20 minutes. The calibration is prepared using calibrations samples with known XS value. XS determination by NMR is based on direct measurement of the ratio of liquid protons to total protons and no weighing is required. Single measurement requires less than 1 minute.

Instrumentation

TD-NMR analyzer Spin Track from Resonance System with 10 or 18 mm test tube is ideal instrument for XS measurements because of fine technical characteristics which make measurements very reproducible and accurate. The device is submitted with tempering device. Spin Track maintains automatic start of the measurement.