A~tract--The flow birefringence of solutions of hydroxypropylcellulose (HPC) in dimethylacetamide and tetrachloroethane has been investigated over a wide range of molecular weights. Comparison of the experimental dependence of shear optical coetficient [n]/[rt] on molecular weight with the theoretic
Conformational properties of hydroxypropylcellulose—I. Hydrodynamic properties and equilibrium rigidity of its macromolecules
✍ Scribed by E.V. Korneeva; I.N. Shtennikova; V.P. Shibaev; S.I. Klenin; G.F. Kolbina; I.V. Ekaeva; S.A. Didenko
- Publisher
- Elsevier Science
- Year
- 1990
- Tongue
- English
- Weight
- 381 KB
- Volume
- 26
- Category
- Article
- ISSN
- 0014-3057
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✦ Synopsis
Hydrodynamic properties (intrinsic viscosity [t/], translational diffusion D and sedimentation So) of samples and fractions of hydroxypropylcellulose (HPC) have been investigated in a number of solvents. The relationships between [q], D and S O and the degree of polymerization of HPC in dimethylacetamide and tetrachloroethane were established. The equilibrium rigidity of HPC molecules was determined from the data on translational diffusion and viscometry; the length of the statistical segment is (210-240) × 10 8 cm. This evaluation of rigidity is in agreement with the rigidity parameters of other cellulose derivatives. It may be assumed that, just as for most mesogenic polymers, it is the high rigidity of the molecules that determines the possibility of mesophase formation in HPC solutions and melts.
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