Method for forming conjugated heteroaromatic homopolymer and copolymer, and products thereof

A method for forming a conjugated heteroaromatic polymer, comprising:

• polymerizing at least one compound of formula (2) using an acid as a catalyst,
• wherein
• X is the same or different at each occurrence, and is independently selected from the group consisting of S, O, Se, Te, PR2 and NR2, wherein R2 is selected from the group consisting of hydrogen, and substituted and unsubstituted alkyl, aryl, heteroaryl, alkanoyl, and aryloy groups;
• Y is hydrogen (H), or a precursor of a good leaving group Y− whose conjugate acid (HY) has a pKa of less than 30;
• Z is hydrogen (H), silyl, or a precursor of a good leaving group Z− whose conjugate acid (HZ) has a pKa of less than 30;
• Ar is a substituted or unsubstituted, mono- or poly-nuclear, aryl or heteroaryl ring;
• m, o and p are each independently an integer equal to or greater than 0, with a proviso that m+p≧1;
• each k is independently 0, 1 or 2;
• each R5 is a substituent, wherein any two R5 on the same ring or on two neighboring rings, or R5 and a substituent group on a neighboring Ar ring, may join together to form another ring;
• the at least one compound of formula (2) being polymerized comprises at least one compound of formula (2) with Z=H and Y≠H that triggers the polymerization;
• the acid as the catalyst is selected from Lewis acids, polymeric acids, and protic acids other than HBr and HCl;
• a polymerization degree of the conjugated heteroaromatic polymer is at least 4;
• the acid as the catalyst initiates the polymerization;
• and
• the at least one compound of formula (2) is polymerized at 2- and 5-positions thereof.