Springer Online Journal Archives 1860-2000
Chemistry and Pharmacology
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Summary The synthesis and characterization of copolyethers based on 1-(4-hydroxyphenyl)-2-(2-methyl-4-hydroxyphenyl)ethane (MBPE), 1,8-dibromooctane and each of the following three nonmesogenic bisphenols: 3,4′-dihydroxydiphenylmethane (3,4′-BPM), 4,4′-isopropylidenediphenol (4,4′-BPA) and 3,4′-isopropylidenediphenol (3,4′-BPA) are presented. Copolymers based on MBPE, 3,4′-BPM and 1,8-dibromooctane display a nematic mesophase up to compositions containing as much as 70 mol% of 3,4′-BPM. The range of mesomorphism decreases on going from 3,4′-BPM to 3,4′-BPA and to 4,4′-BPA. These results demonstrate that structural units derived from parent amorphous and liquid crystalline homopolymers can be isomorphous within the mesophase over a certain range of copolymer composition of the resulting copolymers. Subsequently, the parameters of the mesomorphic phase transitions of these copolymers represent weight averaged values of the corresponding parameters of the parent homopolymers.
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