AbstractThe melting points of three polyethylenes differing in molecular weight distribution from 47,000 to 147,000 were determined as 141°C ± 0.5°C by dilatometric techniques. Sample preparation procedures were developed to ensure uniform thermal history prior to measuring length as a function of temperature in a precision dilatometer. The specific volume data were reproducible within 0.02, reflecting the careful annealing procedure used and the extended time allowed for equilibrium to be attain
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