hours with constant stirring next 0 5 gram of 2 2 diethoxytetrahydrofuran was added and the pressure reduction cycle repeated at 180 u00b0 c and 0 1 mm hg for 16 hours the polymer formed was a light yellow waxy solid soluble in tetrahydrofuran and had the depicted structure where x and y are as previously described and n is 10 to 1000 str17 the procedure of example 18 is repeated with all conditions as described except the u03c3 caprolactone cis trans cyclohexane dimethanol diol is used to yield the following polymer str18 500 grams of l lactic acid with 1 zinc oxide was reacted at 140 u00b0 c at atmospheric pressure for 1 2 hour with the distillation of water after most of the water had distilled vacuum was applied and lactide distilled the lactide was purified by crystallization from methyl ethyl ketone to give 74 grams of product melting at 95 u00b0 to 97 u00b0 c the lactide had the following structure str19 next 4 80 grams of lactide and 2 07 grams of ethylene glycol freshly distilled from 1 sodium was stirred at 130 u00b0 c for 5 hours an ir spectrum in chcl 3 of the product showed a carbonyl band at 1750 cm 1 lactide c 0 absorption 1780 cm 1 and the product distilled at 150 u00b0 c 0 1 mm hg the lactide diol had the structure set forth below where x and y are 1 to 4 r h or ch 3 str20 next diethoxytetrahydrofuran 1 equivalent based on ethylene glycol content and polyphosphoric acid 2 mg per g of diethoxytetrahydrofuran was added to the lactide glycol adduct the solution was stirred under n 2 at 100 u00b0.