Accession Number : ADA175129


Title :   Liquid Crystalline Polymers Containing Heterocycloalkane Mesogens. 2. Side-Chain Liquid Crystalline Polysiloxanes Containing 2,5-Disubstituted-1,3-Dioxane Mesogens.


Descriptive Note : Technical rept.,


Corporate Author : CASE WESTERN RESERVE UNIV CLEVELAND OH DEPT OF MACROMOLECULAR SCIENCE


Personal Author(s) : Hsu,C S ; Rodriguea-Parada,J M ; Percec,V


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a175129.pdf


Report Date : 01 Oct 1986


Pagination or Media Count : 41


Abstract : Polysiloxanes and copolysiloxanes containing 2-(p-hydroxyphenyl)-5-(p-methoxyphenyl)-1,3-dioxane and 5-(p-methoxyphenyl)-1,3-dioxan-2-yl as mesogenic units and an aliphatic spacer containing eleven and respectively, ten methylene units were synthesized. Their phase behavior was studied by differential scanning calorimetry and optical polarization microscopy, and compared with the phase behavior of the polysiloxanes and copolysiloxanes containing 4-meth-oxy-4'-hydroxybiphenyl and 4-cyano-4'-hydroxybiphenyl mesogens attached to the polymer backbone through an aliphatic spacer containing eleven methylene units. All synthesized polymers present smectic mesomorphism. The polymers containing 4-methoxy-4'-hydroxybiphenyl and 4-cyano-4'-hydroxybephenyl are also crystalline, while the polymers containing 1,3-dioxane based mesogens do not crystallize.


Descriptors :   *POLYMERS , *COPOLYMERS , *SILOXANES , SCANNING , POLARIZATION , SYNTHESIS , ALIPHATIC COMPOUNDS , PHASE STUDIES , LIQUID CRYSTALS , MICROSCOPY , OPTICAL ANALYSIS , METHYLENES , CALORIMETRY , SPACERS , DIOXANES


Subject Categories : Polymer Chemistry


Distribution Statement : APPROVED FOR PUBLIC RELEASE