Conjugated polymers and their use in optoelectronic devices

An electronic, optical or optoelectronic device comprising a polymeric semiconductor component, the polymeric semiconductor component comprising a polymer having the formula:

• wherein:
• Ar and Ar′ are identical or different optionally substituted 5-8 membered heteroaryl groups;
• π and π′ are identical or different optionally substituted 11-24 membered polycyclic aryl or heteroaryl groups;
• X1 and X2 independently are selected from the group consisting of N, CH and CR1, provided that at least one of X1 and X2 is CR1;
• X3 is N or CR3;
• X4 is N or CR4;
• R1 is selected from selected from the group consisting of F, Cl, —C(O)R5, —CF2R5, and CN;
• R3 and R4 independently are selected from selected from the group consisting of H, F, Cl, —C(O)R5, CN, R5, OR5, and SR5, wherein R5, at each occurrence, independently is selected from selected from the group consisting of a C1-20 alkyl group and a C1-20 haloalkyl group;
• X is selected from the group consisting of O, S, and NR6, wherein R6 is H or a C1-20 alkyl group;
• a and b independently are 0 or 1;
• m and m′ are 0, 1, or 2;
• n and n′ are 0, 1, or 2, provided that m and m′ are 1 and/or n and n′ are 1, and/or at least one of a and b is 1;
• x and y are real numbers representing mole fractions, wherein 0.05≦x≦0.95, 0.05≦y≦0.95, and the sum of x and y is about 1;
• and
• wherein the polymer has a molecular weight in the range of about 3,000 to about 300,000.