새로운 형태의 액정성 폴리우레탄을 2,6-bis(${omega}$-hydroxyalkoxy)naphthalene (BHNm; m= 5, 6, 8, 11)과 2,5-tolylene diisocyanate 또는 1,4-phenylene diisocyanate의 중부가 반응에 의해 합성하였다. 폴리우레탄의 고유 점성도는 0.28-0.43 dL/g 였다. 열적 성질은 DSC 및 편광현미경에 의해 측정되었다. 단량체 BHNm과 메틸치환기를 가진 2,5-tolylene diisocyanate에 의해 합성된 폴리우레탄은 모두 단방성 액정성을 나타내었다. 그러나 BHNm와 1,4-phenylene diisocyanate를 합성한 폴리우레탄에서는 DSC와 편광현미경으로 조사 결과 전혀 액정성을 나타내지 않았다.
Novel polyurethanes containing no mesogenic unit were synthesized by the polyaddition reaction of para-type diisocyanates such as 2,5-tolylene diisocyanate (2,5-TDI) or 1,4-phenylene diisocyanate (1,4-PDI) with 2,6-bis(${omega}$-hydroxyalkoxy)naphthalene (BHNm; m= 5, 6, 8, 11). Intrinsic viscosities of the polymers were in the range of 0.28-0.43 dL/g. The thermal properties of these polymers were studied by differential scanning calorimetry and polarizing microscopy. Polyurethanes prepared from BHNm and 2,5-TDI haying methyl substituent on the phenylene unit exhibited monotropic liquid crystallinity. However, in the series of polyurethanes prepared from 1,4-PDI and BHNm, no explicit mesomorphic behavior was observed by differential scanning calorimetry and polarizing microscopy.
