ISSN:
1435-1536
Schlagwort(e):
Carboxymethylcellulose
;
electric birefringence
;
optical anisotropy
;
relaxation
;
cluster
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Chemie und Pharmazie
,
Maschinenbau
Notizen:
Abstract The d. c. component of birefringence of aqueous carboxymethylcellulose (CMC) under an a. c. electric field was measured at frequencies ranging from 0.1 Hz to 100 kHz. Three samples of different molecular weights were studied with varying degree of neutralization, polymer concentration and added salt concentration. The dispersion curve of birefringence consists of three relaxation bands,A, B andC in order of decreasing frequency. RelaxationB with a negative relaxation strength is ascribed to end-over-end rotation of almost rodlike CMC molecules. RelaxationA with a positive strength is attributed to the relaxation of electrical polarizability along the minor axis of molecule. RelaxationC possesses also a positive strength and is induced by clusters of CMC molecules.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF01447671
Permalink
