Mark‐Houwink relations for linear polyethylene in 1‐chloronaphthalene and 1,2,4‐trichlorobenzene

The parameters in the Mark‐Houwink relationship, [η] = K ′ M̄ v a , for linear polyethylene in 1‐chloronaphthalene and 1,2,4‐trichlorobenzene at 130°C have been estimated. They were found by measuring the limiting viscosity numbers of a series of fractions with molecular weights ranging from less than 10,000 to almost 700,000. The results are for 1‐chloronaphthalene, [η] =0.0555 M̄ v 0.684 (with a standard error of 0.0064 in K ′ and 0.010 in a ) and for 1,2,4‐trichlorobenzene, [η] = 0.0392 M̄ v 0.725 (with a standard error of 0.00703 in K ′ and 0.015 in a ), where [η] is expressed in ml/g. The unperturbed end‐to‐end distance calculated from the viscosity‐molecular weight data agrees with the theoretically expected value.