Dielectric copolymer materials

Polymerizable mixture comprising a first monomer and a second monomer,

• wherein the first monomer is one or more compound represented by Formula (1), and
• wherein the second monomer is one or more bi- or multifunctional compound capable of reacting with the first monomer to give a copolymer:
• P1-Sp1-(MG-Sp1)m-P1 Formula (1)
• wherein:
• m is an integer from 1 to 60;
• P1 denotes
• Sp1 denotes at each occurrence a spacer group (Sp) or a single bond;
• MG is a rod-shaped mesogenic group, which is preferably selected from Formula (2):
• -(A21-Z21)k-A22-(Z22-A23)l- Formula (2)
• wherein:
• A21 to A23 are independently and at each occurrence independently of one another an aryl group, heteroaryl group, heterocyclic group, alicyclic group or cyclic imide group optionally being substituted by one or more identical or different groups L;
• Z21 and Z22 are independently and at each occurrence independently from each other, —O—, —S—, —CO—, —COO—, —OCO—, —S—CO—, —CO—S—, —O—COO—, —CO—NR01—, —NR01—C)—, —NR01—CO—NR02, —NR01—CO—O—, —O—CO—NR01——OCH2—, —CH2O—, —SCH2—, —CH2S—, —CF2O—, —OCF2—, —CF2S—, —SCF2—, —CH2CH2—, —(CH2)4—, —CF2CH2—, —CH2CF2—, —CF2CF2—, —CH═N—, —N═CH—, —N═N—, —CH═CR01—, —CY01═CY02—, —C≡C—, —CH′CH—COO—, —OCO—CH═CH—, or a single bond;
• R01 and R02 each, independently of one another, denote H or alkyl having 1 to 12 C atoms;
• L is F, Cl, Br, I, —CN, —NO2, —NCO, —NCS, —OCN, —SCN, —C(═O)NRxxRyy, —C(═O)ORxx, —C(═O)Rxx, —NRxxRyy, —OH, —SF5, or straight chain or branched chain alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 20 C atoms, wherein one or more H atoms are optionally replaced by F or Cl, —CN or straight chain or branched chain alkyl, alkoxy, alkylcarbonyl, alkoxycarbonyl, alkylcarbonyloxy or alkoxycarbonyloxy with 1 to 6 C atoms;
• Rxx and Ryy independently of each other denote H or alkyl with 1 to 12 C-atoms;
• Y01 and Y02 each, independently of one another, denote H, alkyl having 1 to 12 C atoms, aryl, F, Cl, or CN;
• and
• k and l are each and independently 0, 1, 2, 3 or 4.