ISSN:
1572-8870
Schlagwort(e):
Polysilane
;
nematic mesophase
;
liquid crystal
;
isotopic phase
;
thermochromic transition
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Chemie und Pharmazie
Notizen:
Abstract Three polysilane polymers, (n-PrSiMe) n , (i-PrSiMe) n , and (sec-BuSiMe) n , were synthesized and characterized by DSC. UV spectroscopy, wide-angle X-ray diffraction, and optical microscopy, all at variable temperatures. The known thermochromic transition of (n-PrSiMe) n at ∼48 C is associated with a change from an orthorhombic to an isotropic phase. (i-PrSiMe) n was examned as an insoluble and soluble (lowM w) fraction, both existing mainly in an orthohombic lattice at room temperature. (sec-BuSiMe) n has a mesophase structure at 25 C, undergoes a weak endothermic transition to a second (nematic) mesophase near 65 C, and becomes isotropic at ∼160 C.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF01157521
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