Abstract:
A new class of liquid crystal compounds is based on tolane and bis-tolane structures: (I), in which X is a polar group such as F (fluoro), CN (cyano), OCF3 (trifluoromethoxy), or NCS (isothiocyanate) at least one of the pairs of sites Y1 and Y2, Z1 and Z2, and for the bis-tolane derivatives, A1 and A2 are fluoro groups. T1 for the tolane derivatives is always a triple bond. For the bis-tolane derivatives, T1 and T2 are either both triple bonds or one of the two groups is a double bond with and the other remains a triple bond. Rn or Rm may be an alkyl group having the general formula CnH2n+1, an alkenyl group having the general formula CnH2n-1, an alkoxy group having the general formula OCnH2n+1, or an alkenoxy group having the general formula -OCnH2n-1. Additionally, for the tolane compounds, Rn may be a cyclohexyl substituent: (II), or a dioxane substituent: (III), in which Rx is an alkyl group having the general formula general formula CxH2x+1, an alkenyl group having the general formula CxH2x-1, an alkoxy group having the general formula OCxH2x+1, or an alkenoxy group having the general formula OCxH2x-1. These compounds exhibit useful nematic ranges and melting points. Also disclosed are eutectic mixtures including these compounds.
Abstract translation:一类新的液晶化合物是以甲苯和双甲苯结构为基础的:(I)其中X为极性基团如氟(氟),CN(氰基),OCF 3(三氟甲氧基)或NCS(异硫氰酸酯) 一对位点Y1和Y2,Z1和Z2中的至少一个以及双甲苯衍生物A1和A2是氟基团。 甲苯衍生物的T1总是三重键。 对于双甲苯衍生物,T1和T2既可以是三重键,也可以是两个基团中的一个是双键,另一个保持三键。 Rn或Rm可以是具有通式CnH2n + 1的烷基,具有通式CnH2n-1的烯基,具有通式OCnH2n + 1的烷氧基或具有通式-OCnH 2 n-1的链烯氧基 。 此外,对于甲苯化合物,R n可以是环己基取代基:(II)或二恶烷取代基:(III),其中R x是具有通式C x H 2 x + 1的通式的烷基,具有通式 式CxH2x-1,具有通式OCxH2x + 1的烷氧基或具有通式OCxH2x-1的烯氧基。 这些化合物表现出有用的向列范围和熔点。 还公开了包括这些化合物的共晶混合物。
Abstract:
A novel compound represented by general formula (I) and a nematic liquid crystal composition containing the same. A compound represented by general formula (I) can be produced with great ease as is shown in an example and has excellent compatibility with a mother liquid crystal of general use being currently used as a nematic liquid crystal, and further shows reduced precipitation at a low temperature. Moreover, the addition of only a small amount of the above compound to the mother liquid crystal results in expanding effectively the temperature range for liquid crystallinity, without detriment to various properties as a liquid crystal material. Accordingly, the above compound is suitable for use in various liquid crystal display elements which are required to have a wide range of working temperature and is greatly useful as a liquid crystal material.
Abstract:
Dielectric compositions encompassing one or more poly(arylene ether) polymers are provided. The dielectric compositions have repetitive structural unit (I) where n=0 to 1; m=0 to 1-n; and Y1, Y2, Ar1 and Ar2 are each a divalent arylene radical, Y1 and Y2 derived from biphenol compounds, Ar1 derived from difluoroarylethynes and Ar2 derived from difluoroaryl compounds. Where both Y1 and Y2 are derived from fluorene bisphenol, n=0.1 to 1. Such poly(arylene ether) polymers are employed with a variety of microelectronic devices, for example, integrated circuits and multichip modules.