Multireactive polymerizable mesogenic compounds

A linear or crosslinked polymer obtained by polymerizing a polymerizable mesogenic compound of formula I

• R1-MG-R2 I
• wherein
• R1 is halogen, CN, OCN, NCS, NO2 or an alkyl radical with 1 to 30 C atoms which may be unsubstituted, mono- or polysubstituted by halogen or CN, optionally one or more non-adjacent CH2 groups being replaced, in each case independently from one another, by —O—, —S—, —NH—, —N(CH3)—, —CO—, —COO—, —OCO—, —OCO—O—, —S—CO—, —CO—S—, —CH═CH— or —C≡C— in such a manner that oxygen atoms are not linked directly to one another, or alternatively has one of the meanings of R2 or is P-(Sp-X)n—,
• P is a polymerizable group selected from CH2═CW—COO—, WCH═CH—O—, CH2═CH-Phenyl-(O)k— and
• with W being H, CH3 or Cl and k being 0 or 1,
• Sp is a spacer group with 1 to 25 C atoms,
• X is —O—, —S—, —CO—, —COO—, —OCO—, —OCO—O—, —CO—NH—, —NH—CO—, —OCH2—, —CH2O—, —SCH2—, —CH2S—, —CH═CH—COO—, —OOC—CH═CH— or a single bond,
• n is 0 or 1,
• MG is a mesogenic group of formula II
• -(A1-Z)m-A2- II
• wherein
• Z is —O—, —S—, —CO—, —COO—, —OCO—, —CO—NH—, —NH—CO—, —CH2CH2—, —OCH2—, —CH2O—, —SCH2—, —CH2S—, —CH═CH—, —CH═CH—COO—, —OCO—CH═CH—, —C≡C— or a single bond,
• A1 and A2 are each independently 1,4-phenylene in which, in addition, one or more CH groups are optionally replaced by N;
• 1,4-cyclohexylene in which, in addition, one or two non-adjacent CH2 groups are optionally replaced by O and/or S;
• 1,4-cyclohexenylene;
• 1,4-bicyclo(2,2,2)octylene;
• piperidine-1,4-diyl;
• naphthalene-2,6-diyl;
• decahydronaphthalene-2,6-diyl;
• or 1,2,3,4-tetrahydro-naphthalene-2,6-diyl;
• all these groups optionally being unsubstituted, mono- or polysubstituted with F, Cl, OH, CN, NO2 or alkyl, alkoxy, alkylcarbonyl or alkoxycarbonyl groups having 1 to 7 C atoms wherein one or more H atoms may be substituted by F or Cl, and
• m is 1, 2 or 3, and
• R2 is alkyl with 1 to 25 C atoms which may be unsubstituted, mono- or polysubstituted by halogen or CN, optionally one or more non-adjacent CH2 groups being replaced, in each case independently from one another, by —O—, —S—, —NH—, —N(CH3)—, —CO—, —COO—, —OCO—, —OCO—O—, —S—CO—, —CO—S—, —CH═CH— or —C≡C— in such a manner that oxygen atoms are not linked directly to one another, and which is substituted with at least two identical or different groups P.

A polarizer, optical retardation or compensation film, alignment layer, colour filter, holographic element, liquid crystal display, PDLC, polymer gel, polymer stabilized cholesteric texture (PSCT) display, adhesive, synthetic resins with anisotropic mechanical properties, cosmetic, diagnostic, liquid crystal pigment for decorative and/or security applications, or article for nonlinear optics or optical information storage comprising a compound of the formula I

• R1-MG-R2 I
• wherein
• R1 is halogen, CN, OCN, NCS, NO2 or an alkyl radical with 1 to 30 C atoms which may be unsubstituted, mono- or polysubstituted by halogen or CN, optionally one or more non-adjacent CH2 groups being replaced, in each case independently from one another, by —O—, —S—, —NH—, —N(CH3)—, —CO—, —COO—, —OCO—, —OCO—O—, —S—CO—, —CO—S—, —CH═CH— or —C≡C— in such a manner that oxygen atoms are not linked directly to one another, or alternatively has one of the meanings of R2 or is P-(Sp-X)n—,
• P is a polymerizable group selected from CH2═CW-COO—, WCH═CH—O—, CH2═CH-Phenyl-(O)k— and
• with W being H, CH3 or Cl and k being 0 or 1,
• Sp is a spacer group with 1 to 25 C atoms,
• X is —O—, —S—, —CO—, —COO—, —OCO—, —OCO—O—, —CO—NH—, —NH—CO—, —OCH2—, —CH2O—, —SCH2—, —CH2S—, —CH═CH—COO—, —OOC—CH═CH—0 or a single bond,
• n is 0 or 1,
• MG is a mesogenic group of formula II
• -(A1-Z)m-A2- II
• wherein
• Z is —O—, —S—, —CO—, —COO—, —OCO—, —CO—NH—, —NH—CO—, —CH2CH2—, —OCH2—, —CH2O—, —SCH2—, —CH2S—, —CH═CH—, —CH═CH—COO—, —OCO—CH═CH—, —C≡C— or a single bond,
• A1 and A2 are each independently 1,4-phenylene in which, in addition, one or more CH groups are optionally replaced by N;
• 1,4-cyclohexylene in which, in addition, one or two non-adjacent CH2 groups are optionally replaced by 0 and/or S;
• 1,4-cyclohexenylene;
• 1,4-bicyclo(2,2,2)octylene;
• piperidine-1,4-diyl;
• naphthalene-2,6-diyl;
• decahydronaphthalene-2,6-diyl:
• or 1,2,3,4-tetrahydro-naphthalene-2,6-diyl;
• all these groups optionally being unsubstituted, mono- or polysubstituted with F, Cl, OH, CN, NO2 or alkyl, alkoxy, alkylcarbonyl or alkoxycarbonyl groups having 1 to 7 C atoms wherein one or more H atoms may be substituted by F or Cl, and
• m is 1, 2 or 3, and
• R2 is alkyl with 1 to 25 C atoms which may be unsubstituted, mono- or polysubstituted by halogen or CN, optionally one or more non-adjacent CH2 groups being replaced, in each case independently from one another, by —O—, —S—, —NH—, —N(CH3)—, —CO—, —COO—, —OCO—, —OCO—O—, —S—CO—, —CO—S—, —CH═CH— or —C≡C— in such a manner that oxygen atoms are not linked directly to one another, and which is substituted with at least two identical or different groups P.