摘要 |
The present invention relates to compounds represented by the following Formula I, In Formula I, R1 and R2 are each independently selected from hydrogen, and optionally substituted hydrocarbyl, provided that at least one of R1 and R2 is selected from optionally substituted hydrocarbyl (e.g., tertiary butyl); n is 0, 1 or 2, and each R3 is independently selected from optionally substituted hydrocarbyl; L1 is a divalent linking group, such as a bond or—C(O)O—; each L2 independently represents a flexible segment, such as divalent linear or branched C1-C25 alkyl; each L3 independently represents a rigid segment including, for example, optionally substituted phenylen-1,4-diyl groups; t is from 1 to 4; m and p are each independently from 0 to 4 for each t, provided that the sum of m and p is at least 1 for each t; and E can be, for example, C5-C18 aryl. The present invention also relates to compositions, such as liquid crystal compositions, and articles, such as optical elements, that include the compound represented by Formula I.
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