Polymer and organic solar cell including the same

A polymer selected from one of the following structures:

• wherein
• A1 and A2, are independently a halogen group;
• A3, and A4 are independently hydrogen or a halogen group;
• R107, R108, R207 and R208 are the same as or different from each other, and are each independently a substituted or unsubstituted alkoxy group;
• R111 and R112 are independently a substituted or unsubstituted alkyl group, a substituted or unsubstituted silyl group, or a substituted or unsubstituted alkylthio group when A3 or A4 is a halogen group, and independently a substituted or unsubstituted silyl group or a substituted or unsubstituted alkylthio group when A3 and A4 are hydrogen and an acceptor unit of the polymer is benzothiadiazole;
• R311 and R312 are independently a substituted or unsubstituted alkoxy group or a substituted or unsubstituted alkoxy substituted phenyl group;
• R411 and R412 are independently a substituted or unsubstituted alkyl group or a substituted or unsubstituted alkoxy group;
• R9, R10 and R19 are independently hydrogen, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryloxy group, a substituted or unsubstituted alkylthio group, a substituted or unsubstituted arylthio group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group;
• l is a mole fraction and is a real number of 0<l<1;
• m is a mole fraction and is a real number of 0<m<1;
• l+m=1;
• and
• n is a repetition number of the unit and is an integer of 1 to 10,000.