LAUSR

Abstract Poly(ethylene oxides) with different densities of entanglements of macromolecules, even reduced by half, were obtained by dissolving the polymer in water, freezing the solution and removing the water by drying. We examined the effect of the reduction of the macromolecular entanglements on the polymer crystallization under isothermal and non-isothermal conditions. It turned out that with a decrease in entanglement density, spherulitic nucleation increases, and the resulting spherulites grow faster. These reduced the time of total crystallization from melt. With less macromolecular entanglements, the temperature of transition between crystallization regimes I and II shifted in the direction of lower temperatures. X-ray observations of the size of the formed lamellas have shown that slightly thicker and more perfect crystals grew from a partially disentangled melt. The macromolecules in the samples annealed in the melt gradually re-entangle, but this process is slow.