in addition to the ped and the terephthalic acid the usual terminators used in the laboratory were benzoic acid and cyclohexylamine examples of polymer batches with their analyses are listed below in table ii all batches were made with 23 ppm manganous chloride and 53 ppm hypophosphorous acid increasing concentrations of ped t results in polymers with lower solution viscosity fav at same total ends block copolymers of nylon and ped t have a significantly lower melt viscosity than pure nylon with the same number of end groups table iii this is probably because of the high degree of flexibility of the polyether chain and is consistent with the polyether component being soluble in the nylon melt viscosities are given only at a shear rate of 2000 sec 1 and a temperature of 260 u00b0 c on the basis of these data fav correlates with melt viscosity better than number average molecular weight total ends the ped polymer did not have a measurably lower melting point even with 20 by weight of ped t the calculated reduction in melting point was only 0 9 u00b0 c the glass transition temperature is however decreased substantially by ped t these data are shown in table iv the differential scanning calorimeter analysis was performed on a dupont model 1090 thermal analyzer the solid polymer was heated in nitrogen at the rate of 10 u00b0 c per minute the temperature at the peak of the endotherm was taken as the melting point tm the temperature was raised to 255 u00b0 c and held for 5 minutes it was then quenched in liquid nitrogen to produce an amorphous solid the polymer was then.