We present results for step-strain experiments and the resulting damping functions of polyethylene blends of different structures, including solutions of linear, star and comb polymers. Remarkably, an entangled melt of combs exhibits a damping function close to that for entangled linear chains. Diluting the combs with fasterrelaxing material leads to a more nearly constant damping function. We ...

The experimental timescale of memory effects related to restoring equilibrium viscoelastic properties in solution-cast linear and long-chain branched polyethylenes has been investigated. It was found that the crystallization history of low-density polyethylene and ultra-high-molecular-weight polyethylene, with respect to solid-state and melt properties, is lost after heating into the melt after...