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RESEARCH PRODUCT

Composition-dependent Flory-Huggins parameters: molecular weight influences at high concentrations

Bernhard A. WolfHans-michael Petri

subject

chemistry.chemical_classificationPolymers and PlasticsOrganic ChemistryEnthalpyCyclohexanoneConcentration effectPolymerFlory–Huggins solution theoryCondensed Matter PhysicsLight scatteringSolventchemistry.chemical_compoundchemistryPolymer chemistryMaterials ChemistryPolystyrenePhysical and Theoretical Chemistry

description

Flory-Huggins interaction parameters X were determined by means of equilibrium vapor pressures (measured via a combination of a head-space sampler with a gas chromatograph) and light scattering as a function of composition and temperature for the systems cyclohexanone/polystyrene [CHO/PS] and cyclohexanone/poly(butyl methacrylate) [CHO/PBMA]. The investigation of molecular weight influences on X with the system CHO/PBMA demonstrates that they persist almost up to the pure polymer. In order to rationalize this result, it is postulated (in accord with experimental findings and theoretical predictions) that the dimensions of polymer chains may vary upon the addition of solvent even in highly concentrated solutions. From the information concerning X (T) the interaction parameters were split into their enthalpy and entropy part. In the case of CHO/PS these quantities vary considerably with composition and turn out to be linearly interrelated.

yearjournalcountryeditionlanguage
1995-07-01Macromolecular Chemistry and Physics
https://doi.org/10.1002/macp.1995.021960719