The friction torque on the outer ring of a tapered roller bearing has been experimentally measured for a mineral oil (base oil), as well as for samples of the base oil additived with low-density polyethylene. The data show an important reduction of friction by introducing the polymer into the base oil due to the film formed by the adsorption of macromolecular coils on the solid surface. The effectiveness of macromolecular additive contribution to

The viscometric behaviour of polyacrylonitrile solutions in dimethylformamide has been examined in different regimes of concentration. For semidilute and concentrated solutions, viscoelastic properties were determined and discussed. The viscosity - concentration curves show some specific behaviours for polyacrylonitrile solutions at very low and high concentrations. The overlap concentration was evidenced as being the crossover of two scaling laws

Experimentally obtained islands of immiscibility are reported for the systems PS/PVME/THF at 20°C and for PS/PVME/CH at 55°C (PS: polystyrene, PVME: poly(vinyl methyl ether), THF: tetrahydrofuran, CH: cyclohexane). THF is a good solvent and CH is a marginal solvent for both polymers. In the case of THF, information on the Flory−Huggins interaction parameters of the three binary subsystems suffices for a qualitative prediction of the phase behavior

Equilibrium vapor pressures, p, are reported for the systems tetrahydrofuran + poly(vinyl methyl ether) and tetrahydrofuran + polystyrene at 20, 40, and 60 °C. These data plus information from the literature serve to demonstrate that the composition dependence of p can be modeled quantitatively for polymer solutions in thermodynamically very different solvents by means of three, physically meaningful parameters.