ISSN:
1435-1536
Keywords:
Branchedpolyethylene
;
equilibriummelting point
;
enthalpy offusion
;
surface free energy
;
kinks
;
chain defects
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract New equilibrium melting point data, for polyethylene containing chain defects, are tested in the light of random copolymer predictions. A simplified expression for the melting point depression of random copolymers containing small amounts of non-crystallizable units is derived. Non-equilibrium melting data for rapidly quenched polyethylene samples are also reported. The fusion enthalpyΔH∘(X), and the surface free energyσ e for crystals containing defects are evaluated using crystallinity, equilibrium meltingtemperatures and X-ray long period data. It is shown that increasing defect penetration within crystals induces a decrease ofΔH∘(X) withX in accordance with theoretical predictions. Finallyσ e is, similarly, shown to decrease with increasing number of chain defects attached to the crystal surface.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01412713
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