Polysilsesquioxane-dendron liquid crystals and method for preparing the same

A method for preparing a liquid crystal compound of the following formula 9 which has POSS-dendron structure, comprising:

• (i) reacting alkyl chain (R1) with mesogen (M) in a weight ratio of 1:0.8-1.5;
• (ii) reacting the R1-M obtained in the step (i) with R2 in a weight ratio of 1:2-4;
• (iii) reacting the R1-M-R2 obtained in the step (ii) with benzoate in a certain weight ratio to form R1-M-R2—Ar;
• and
• (iv) reacting the R1-M-R2—Ar with polysilsesquioxane,
• where M is mesogen of compound of the formula 6,
• R1 is CF3(CF2)nCH2CH2OH, CH3(CH2)nBr, CH3(CH2)nOH, CH3(OCH2CH2)nOH, CH3(OCH2CH2)nBr, CF3(CF2)nBr, CF3(CF2)nI, CF3(CF2)nCH2I, CF3(CF2)nCH2OH, CF3(CF2)nCH2CH2I or CH3(CH2)nCl;
• R2 is Cl(CH2)nCl, Br(CH2)nBr, HO(CH2)nOH, ClCH2(CH2OCH2)nCH2Cl, Cl(CF2)nCl, I(CF2)nI, Br(CF2)nBr, HOCH2(CH2OCH2)nCH2OH, or HOCH2(CF2)nCH2OH;
• Ar is benzene;
• and
• P is polysilsesquioxane.

A method for forming a liquid crystal display device comprising:

• providing a liquid crystal material;
• adding a liquid crystal compound to the liquid crystal material;
• and
• using the liquid crystal material with the added liquid crystal compound to form a liquid crystal layer having an upper side and a lower side;
• wherein the liquid crystal compound improves alignment of liquid crystal molecules of the liquid crystal layer, or enhances orientation of the liquid crystal molecules by being located at either or both of the upper side or lower side of the liquid crystal layer;
• wherein the liquid crystal compound is of the formula 1 which has POSS-dendron structure:
• where Ar is C6-C20 aryl,
• P is polysilsesquioxane,
• Ar and P are linked with oxygen or NCO group,
• R1 and R2 are independently C1-C30 hydrocarbon,
• M is mesogen of compound of the formula 6, and
• m is 1-3
• where A is —O—, —COO—, —OCO— or —NHCO—;
• B is S, O, N2 or (CH2)n;
• and n is 1-20.