a hazy solution aqueous hydrochloric acid was added dropwise until the solution ph was 1 2 a precipitate that formed was filtered and washed with water until the washings were neutral and allowed to air dry the product was dissolved in ether and washed with 1 aqueous hydrochloric acid and with 100 ml of saturated sodium bicarbonate the latter washing resulted in formation of an emulsion so aqueous hydrochloric acid was added to a ph of about 2 the ether phase was separated dried over anhydrous magnesium sulfate and concentrated on a rotary evaporator the solid was dissolved in thf and mixed with 10 ml of 18 aqueous hydrochloric acid this mixture was poured into 3 l of water the precipitate that formed was filtered washed with water until the washings were neutral and dried in a vacuum oven to give 21 9 g of polymer 19 f nmr a acetone d 6 74 2 u2202 assigned to units from the nb u2014 f u2014 o t buac u2212 76 9 s assigned to units from nb u2014 f u2014 oh and u2212 95 to u2212 125 m assigned to units from tfe by integration of the spectrum the composition of the polymer was found to be 46 tfe 30 nb u2014 f u2014 oh and 24 nb u2014 f u2014 o t buac tg 132 u00b0 c by dsc samples of.