Polymer characterization by coupling gel‐permeation chromatography and automatic viscometry

Abstract

synopsisA method is proposed for use of the universal calibration curve, i.e., the product of molecular weight and intrinsic viscosity versw retention volume, in calculating the molecular weight distribution of a polymer from gel-permeation chromatography (GPC) when the Mark-Houwink relation of the polymer in the solvent used for the GPC is unknown. This is achieved by measuring the viscosity of each fraction with an automatic capillary tube viscometer. Application of this technique to poly(viny1 chloride) and poly(viny1 acetate) proved to be successful. J . P o l~t n .Sci. A-2, 5,313 (1967).

Mark–Houwink relationship of the system PVC/N‐methylpyrrolidone (NMP)

“…[q]Eh$ = 1.66 X 10-2M0,76 cm3/g (6) The relatively high value of the exponent a reflects the high dissolving power of N-methylpyrrolidone. In order to obtain some quantitative assessment of the degree of approximation of eq.…”

Surfactant concentration effects on the microemulsion polymerization of vinyl acetate

“…The chromatographic equipment consisted of a Knauer HPLC64 pump, two PL-gel MIXED-B columns (Polymer Laboratories) and a Knauer differential refractometer as a detector. The GPC was calibrated with narrow polystyrene standards (Polymer Laboratories); the molar masses were calculated with the viscosimetric equation for poly(vinyl acetate) or PVA in THF, ½hZ 3:5 !10 K4 M 0:63 [16]. This calibration was verified using PVA standards (Polymer Laboratories).…”

Effective refractive index and intermolecular forces associated with a phase of functional groups

“…There are many studies on the additive properties of refractive index, molar refraction and the contribution of various functional groups to these quantities (see for example [20][21][22][23][24][25][26]). These studies are related to the prediction of the bulk average refractive index of a molecule.…”