We analyze a system consisting of two spherical particles immersed in a polydispersed polymer solution under theta conditions. An exact theory is developed to describe the potential of mean force between the spheres for the case where the polymer molecular weight dispersity is described by the Schulz-Flory distribution. Exact results can be derived for the protein regime, where the sphere radiu...

9-Amino-9-phosphabicyclo[3.3.1]nonanes, (PhobPNHR'; R = Me or (i)Pr) are readily prepared by aminolysis of PhobPCl and are significantly less susceptible to hydrolysis than the acyclic analogues Cy2PNHR'. Treatment of Cy2PNHMe with Cy2PCl readily gave Cy2PNMePCy2. By contrast, treatment of PhobPCl with PhobPNHMe in the presence of Et3N does not afford PhobPNMePPhob but instead the salt [PhobP(=...

In this study, a mathematical model for the time evolution of molecular weight distribution (MWD) was developed. This temporal is based on well-known Ziegler–Natta polymerization mechanism and reaction kinetics by parametric solving related differential equations. However, due to generality reactions involved, can be extended other type catalysts, such as metallocenes, Phillips, etc. The superi...

We here present a statistical model of hydrogen bond induced network structures in liquid alcohols. The model generalises the Andersson-Schulz-Flory chain model to allow also for branched structures. Two bonding probabilities are assigned to each hydroxyl group oxygen, where the first is the probability of a lone pair accepting an H-bond and the second is the probability that given this bond al...

We developed an analytical theory for the many-body potential of mean force (POMF) between N spheres immersed in a continuum chain fluid. The theory is almost exact for a Θ polymer solution in the protein limit (small particles, long polymers), where N-body effects are important. Polydispersity in polymer length according to a Schulz-Flory distribution emerges naturally from our analysis, as do...

ethylene was homopolymerized over ziegler-natta catalyst and the homopolymerization was modeled using moment equations. mechanism was modeled according to five different reaction centers of catalyst. for each center, there are different reaction rate coefficients; therefore the final product of each center would be expected to be different. modeling results showed good conformity to the experim...

Editorial Board: s. A. ADIBI N. C. ANDERSON, JR. T. BERGLINDH H. J. BINDER H. G. BOHLEN J. CHRISTENSEN M. FIELD J. G. FORTE R. A. FRIZZELL J. D. GARDNER D, N. GRANGER S. J. HERSEY U. HOPFER K. A. HUBEL R. LESTER L. M. LICHTENBERGER T. E. MACHEN G. M. MAKHLOUF H. MURER J. D. OSTROW D. W. POWELL R. C. ROSE D. SCHACHTER H. P. SCHEDL G. A. SCHEELE I. SCHULZ A. P. SHEPHERD, JR. Y.-F. SHIAU A. H. SOL...