Abstract
Generic polymer models capturing the chain connectivity and excluded-volume interactions between polymer segments can be clas-sified,according to whether or not the 3D integral of the latter diverges,into hard-and soft-core models.Taking homogeneous systems of com-pressible homopolymer melts(or equivalently homopolymer solutions in an implicit,good solvent)in the continuum as an example,we recently compared the correlation effects on the structural and thermodynamic properties of the hard-and soft-core models given by the polymer refer-ence interaction site model(PRISM)theory with the Percus-Yevick(PY)closure(Polymers 2023,15,1180).Here we analyzed in detail the numeri-cal errors and behavior of the interchain pair correlation functions(PCFs)given by the PRISM-PY calculations of these models using an efficient numerical approach that we proposed.Our numerical approach has the least number of independent variables to be iteratively solved,analytical-ly treats the discontinuities caused by the non-bonded pair potential(such as that of the hard spheres)and takes only the inverse Fourier trans-form of the interchain indirect PCF between polymer segments(which is continuous and decays towards 0 with increasing wavenumber much faster than both the interchain direct and total PCFs),and is essential for us to accurately solve the PRISM-PY theory for chain length N as large as 106.To capture the correlation-hole effect,the real-space cut-off in the PRISM calculations should be proportional to the square root of N.
基金项目
American Chemical Society Petroleum Research Fund()
维普
万方数据