Method for the preparation of photoaligning polymer materials and compositions

A process for the preparation of a photoaligning polymer material comprising aryl acrylic acid ester groups comprising the steps of:

• a. reacting a compound of formula (II)
• wherein:
• ring C is phenylene which is unsubstituted or optionally substituted with fluorine, chlorine, cyano, alkyl or alkoxy, pyrimidine-2,5-diyl, pyridine-2,5-diyl, 2,5-thiophenylene, 2,5-furanylene, 1,4- or 2,6-naphthylene,
• Y is either C or O;
• and
• if Y is C then m=1 and R═COOR′,
• wherein R′ is straight-chain or branched alkylene group with 1 to 20 carbon atoms which is optionally at least once substituted with halogen or with at least one siloxane moieties, or a cycloalkyl residue with 3 to 8 ring atoms which is optionally substituted with at least one halogen, alkyl or alkoxy;
• or
• if Y is 0, then m=0;
• with a compound of formula (III)
• M1 signifies a repeating monomer unit from the group consisting of acrylate, methacrylate, 2-chloroacrylate, 2-phenylacrylate, acrylamide, methacrylamide, 2-chloroacrylamide, 2-phenylacrylamide, N-lower alkyl substituted acrylamide, N-lower alkyl substituted methacrylamide, N-lower alkyl substituted 2-chloroacrylamide, N-lower alkyl substituted 2-phenylacrylamide, vinyl ether, vinyl ester, styrene, diamine, amide, imide, siloxane, amic ester, and amic acid;
• S1 is a spacer unit;
• ring A signifies phenylene which is unsubstituted or optionally substituted with fluorine, chlorine, cyano, alkyl or alkoxy, pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,3-dioxane-2,5-diyl, cyclohexane-1,4-diyl, piperidine-1,4-diyl or piperazine-1,4-diyl;
• ring B signifies phenylene which is unsubstituted or optionally substituted with fluorine, chlorine, cyano, alkyl or alkoxy, pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,4- or 2,6-naphthylene, 1,3-dioxane-2,5-diyl or cyclohexane-1,4-diyl;
• Y1, Y2 each independently signify a single covalent bond, —(CH2)t—, —O—,
• —CO—, —CO—O—, —O—OC—, —CF2O—,—OCF2—, —NR4—, —CO—NR4—, —R4N—CO—, —(CH2)t—, —O—,
• O—, —O—(CH2)u—, —(CH2)u—NR4— or —NR4—(CH2)u—, in which
• R4 signifies hydrogen or lower alkyl;
• T signifies a whole number of 1 to 4;
• u signifies a whole number of 1 to 3;
• and
• m, n signifies a whole number of 0 to 4;
• and
• optionally with a compound of formula (IV) or (IV′)
• and
• b. optionally reacting the compound obtained under step a. with a compound of formula (V)
• X—(CZqZ′q′)—CZrZ′r′ (V)
• wherein X is OH, F, Cl or I;
• Z and Z′ are independently from each other either H or halogen;
• q and q′ are independently from each other an integer between 0 and 2;
• p is an integer between 0 and 10
• r and r′ are independently from each other an integer between 0 and 3;
• c. polymerizing the compound obtained under step a. or b. with an organic or inorganic peroxide;
• d. stopping the reaction by heating.