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Abstract

A pulsed nmr analysis system for polymers materials extracted from industrial processes at a mobility enhancing temperature (at or above glass transition temperature for amorphous polymers, at the crystalline transition temperature for crystalline and semi-crystalline polymers). The sample is measured via nmr techniques and results correlated to viscosity and melt index or melt flow (which are related to average molecular weights). The nmr system (in or out of resonance) includes: sample throughput system (P, LI, V1, V2) and user system controls (104) to establish digitized free induction decay curves (C), from which components functions are determined using linear or non-linear regression techniques to correlate the curve components to the target nuclei and to flow rates in plastics. Substantial improvement of correlation of nmr derived constants and equations of a free induction decay curve with the foregoing polymer properties is obtained via (1) conducting the nmr process at a mobility enhancing temperature (normally elevated compared to the industrial process temperature of the industrial process) and (2) holding temperature substantially constant at such elevated temperature.

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