TECHNOLOGY FOCUS - POLYMERS - Preferred Method: In the method (M1), the modifying is a functionalization of the polymer (P1); or forming a conjugated polymer or substituting at least a part of the dithiocarbamate moieties to thereby introduce another functionality; and the modifying includes protonation of at least a part of the dithiocarbamate moieties. In the method (M1), the acid is used in an amount of 0.1-3 molar equivalents of the dithiocarbamate moieties present in the polymer (P1); and the step of reacting the polymer (P1) with the acid is performed at a temperature of -30 to +130 (preferably 20-100) degrees C. The method (M1) prepare a polymer product of formula -(Ar-C(R3)=C(R4))n- (III). The method (M1) further involves adding a nucleophile agent in an amount of 0.1-10 molar equivalents of the dithiocarbamate moieties present in the polymer (I). The product of addition of the nucleophile agent is a polymer or copolymer comprising repeating units of formula -(Ar-C(R3)(Nu)-CH(R4))n- (IV).Nu=monovalent group derived from the nucleophile agent selected from OR5, SR5, NHR6, OC(O)R5, SC(O)R5;andR5 and R6=1-20C alkyl, 2-20C alkenyl or aryl.Preferred Components: The nucleophile agent is selected from alcohols, thiols, phenols, thiophenols, dialkylsulfurs, aminoalkanes, anilines, carboxylic acids, carboxylic aldehydes, carboxylic acid esters, thiocarboxylic acids and its esters, xanthates, carboxylic acid amides, amino-acids, peptides, nucleosides, heterocyclic bases, alkaloids and modified DNA. The acid exhibits a pKa from -10 to +11, where the acid is organic acid selected from carboxylic acids, phosphonic acids and sulfonic acids; or inorganic acid. Preferred Definitions:    Ar=aromatic or heteroaromatic divalent group selected from 1,4-phenylene, 2,6-naphthalenediyl, 1,4-naphthalenediyl, 1,4-anthracenediyl, 2,6-anthracenediyl, 9,10-anthracenediyl, 2,5-thienylene, 2,5-furanediyl, 2,5-pyrrolediyl, 1,3,4-oxadiazole-2,5-diyl, 1,3,4-thiadiazole-2,5-diyl, 2,3-benzo(c)thienylene, thieno(3,2-b)thiophene-2,5-diyl, pyrrolo(3,2-b)pyrrole-2,5-diyl, pyrene-2,7-diyl, 4,5,9,10-tetrahydropyrene-2,7-diyl, 4,4'-biphenylene, phenantrene-2,7-diyl, 9,10-dihydrophenantrene-2,7-diyl, dibenzofurane-2,7-diyl or dibenzothiophene-2,7-diyl.    EXAMPLE - No suitable example is given.