@article {Kolinski1987c, title = {Monte Carlo studies on the long time dynamic properties of dense cubic lattice multichain systems. II. Probe polymer in a matrix of different degrees of polymerization}, journal = {The Journal of Chemical Physics}, volume = {86}, year = {1987}, pages = {7174{\textendash}7180}, abstract = {The dynamics of a probe chain consisting of nP =100 segments in a matrix of chains of length of nM=50 up to nM=800 at a total volume fraction of polymer ϕ=0.5 have been simulated by means of cubic lattice Monte Carlo dynamics. The diffusion coefficient of the probe chain over the range of nM under consideration decreases by about 30\%, a behavior rather similar to that seen in real melts of very long chains. Furthermore, the analysis of the probe chain motion shows that the mechanism of motion is not reptation-like and that the cage effect of the matrix is negligible. That is, the local fluctuations of the topological constraints imposed by the long matrix chains (even for nM=800) are sufficiently large to provide for essentially isotropic, but somewhat slowed down, motion of the probe, nP =100, chains relative to the homopolymer melt. The results of these MC experiments are discussed in the context of theoretical predictions and experimental findings for related systems.}, keywords = {Chains, Computerized Simulation, dynamics, Liquid Structure, Matrix Isolation, Melts, Monte Carlo Method, Polymerization, Polymers}, doi = {10.1063/1.452367}, url = {http://link.aip.org/link/JCPSA6/v86/i12/p7174/s1}, author = {Andrzej Koli{\'n}ski and Jeffrey Skolnick and Robert Yaris} }