Method for preparing processable polyisothianaphthene

A method for preparing a processable polyisothianaphthene polymer as follows:

• ##STR9## wherein either one of R.sub.1 and R.sub.2 is selected from a group consisting of hydrogen, alkyl group having one to eight carbon atoms, alkoxyl group having one to eight carbon atoms, alkyl sulfide group, cyanide group, chlorine, and bromine, X is one selected from a group consisting of S, Se, and Te, and n is an integer ranged from 5 to 500, comprising steps of:
• (a) dissolving an isothianaphthene monomer having a formula as follows in a solvent wherein R.sub.1, R.sub.2, and X are the same as defined above, ##STR10## and introducing an initiator to initiate a polymerization reaction to produce a precursor of poly(dihydroisothianaphthene) having a formula as follows wherein R.sub.1, R.sub.2, X, and n are the same as defined above;
• ##STR11## (b) dissolving thoroughly said precursor of poly(dihydroisothianaphthene) as a solute in said solvent in an appropriate ratio to obtain a poly(dihydroisothianaphthene) solution;
• (c) proceeding a dehydrogenation reaction for said poly(dihydroisothianaphthene) solution by introducing a dehydrogenation agent to obtain a polyisothianaphthene microgel solution, wherein said dehydrogenation agent is one selected from a group consisting of tert-butyl hypochlorite (tBHC) and sulfuryl chloride (SO.sub.2 Cl.sub.2);
• and
• (d) terminating said dehydrogenation reaction by introducing an inhibitor.