TECHNOLOGY FOCUS - POLYMERS - Preparation: No general method for preparation of the polymer (P1) is given. Preferred Compound: The polymer (P1) further comprises a third comonomer repeat unit different from the first and second comonomer repeat units. The polymer (P1) comprises a first comonomer repeat unit including the moiety (I); and a second comonomer repeat unit comprising a thiophene moiety (substituted by 1-20C alkyl, 1-20C alkoxy, 3-20C cycloalkyl, 1-20C heterocycloalkyl, (hetero)aryl, halo, CN, OR', C(O)R', C(O)OR' or SO2R', preferably substituted by hexyl); thiophene moiety fused by a 1,4-dioxane moiety; or other than unsubstituted thiophene moiety.R'=H, 1-20C alkyl, 1-20C alkoxy, (hetero)aryl, 3-20C cycloalkyl or 1-20C heterocycloalkyl.Preferred Components: The second comonomer repeat unit comprises heterocyclic moiety selected from list of 33 moieties as given in the specification e.g. benzothiadiazole moiety of formula (II), thiadiazoloquinoxaline moiety of formula (III), cyclopentadithiophene dioxide moiety of formula (IV), benzoisothiazole moiety of formula (V) or thiazole moiety of formula (VI). The third comonomer repeat unit comprises a thiophene moiety (preferably thiophene moiety optionally substituted by hexyl).R5 and R6,=R1 (preferably H or hexyl);R7=H, 1-20C alkyl, 1-20C alkoxy, (hetero)aryl, 3-20C cycloalkyl or 3-20C heterocycloalkyl. Preferred Definitions:    R1 and R2=hexyl.    EXAMPLE - A Schlenk flask (100 ml) was charged with bis-(5,5'-trimethylstannyl)-3,3'-di-n-hexyl-silylene-2,2'-dithiophene (0.045 g), 5,5'-bis(5-bromo-2-thienyl)-4,4'-dihexyl-2,2'-bithiazole (0.043 g), tris-dibenzylideneacetonedipalladium (0) (1 mg), and triphenylphosphane (2 mg). The flask was evacuated and refilled with argon three times. The solids were dissolved in o-xylene (3 ml) and the solution was heated to 95degrees C for 24 hours. The solution was then cooled, poured into stirring methanol (500 ml), and filtered. After work a polymer (0.069 g) was obtained, where the polymer had number-average molecular weight (Mn) of 3.7 kDa; and weight-average molecular weight and (Mw) of 4.6 kDa.