Polymer science model polymers

Bhattacharyya, A. and Tobushi, H. (2000) Analysis of the isothermal mechanical response of a shape memory polymer rheological model. Polymer Engineering and Science, 40, 2498-2510. 

Goto, S., K. Yamamoto, S. Furui and M. Sugimoto. Computer Model for Commercial High-Pressure Polyethylene Reactor Based on Elementary Reaction Rates Obtained Experimentally Journal of Appl. Polym. Science Appl. Polym. Symposium, 36 (1981), 21-40. 

Carnaby, G.A., Postle, R. (1991), Discrete fiber versus continuum models in the mechanics of staple yarns, Jom-nal of Applied Polymer Science Applied Polymer Symposium, 47, pp. 341-354... 

In Part I the various aspects related to polymeric, dense metallic and composite membranes for membrane reactors are extensively considered. The volume starts with Chapter 1, in which the authors (Vital and Sousa) give an overview of the polymeric membranes used in membrane reactors. After introducing some basic concepts of polymer science and polymer membranes, two different types of polymeric membrane reactors (inert and catalytic) are discussed. Various examples of the main reactor types (extractors, forced-flow or contactors) are also given. Finally, the modelling aspects of membrane reactors with dense polymeric catalytic membranes are also presented in detail. It is followed by Chapter 2 (Basile,Tong and Millet), which... 

Coarse-grained models have a longstanding history in polymer science. Long-chain molecules share many common mesoscopic characteristics which are independent of the atomistic stmcture of the chemical repeat units [4, 5 and 6]. The self-similar stmcture [7, 8, 9 and 10] on large length scales is only characterized by a single length scale, the chain extension R. 

L. Monnerie, U. W. Suter, eds. Atomistic Modeling of Physical Properties. Advances in Polymer Science No. 116. Berlin Springer, 1994. 

A. A. Gusev, F. Muller-Plathe, U. W. Suter, W. F. van Gunsteren. In L. Monnerie, U. W. Suter, eds. Atomistic Modeling of Physical Properties, Advances in Polymer Science No. 116. Berlin Springer 1994, pp. 207-248. 

Artificial Neural Networks as a Semi-Empirical Modeling Tool for Physical Property Predictions in Polymer Science... 

Dorn, K., Hupfer, B., and Ringsdorf, H. Polymeric Monolayers and Liposomes as Models for Biomembranes How to Bridge the Gap Between Polymer Science and Membrame Biology Vol. 64, pp. 1 —54. 

Our laboratory has planned the theoretical approach to those systems and their technological applications from the point of view that as electrochemical systems they have to follow electrochemical theories, but as polymeric materials they have to respond to the models of polymer science. The solution has been to integrate electrochemistry and polymer science.178 This task required the inclusion of the electrode structure inside electrochemical models. Apparently the task would be easier if regular and crystallographic structures were involved, but most of the electrogenerated conducting polymers have an amorphous and cross-linked structure. 

The polymer-solvent interaction parameter, which is a key constant defining the physical chemistry of every polymer in a solvent, can be obtained from electrochemical experiments. Definition and inclusion of this interaction was a milestone in the development of polymer science at the beginning of the 1950s. We hope that Eq. 47 will have similar influence in the development of all the cross-interactions of electrochemistry and polymer science by the use of the ESCR model. A second point is that Eq. 47 provides us with an efficient tool to obtain this constant in electroactive... 

Journal of Applied Polymer Science 60, No. 10, 6th June 1996, p. 1637-44 CONTRIBUTION TO THE MODELLING OF PREDEPOLYMERISATION OF POLYSTYRENE... 

The computer has become an accepted part of our daily lives. Computer applications in applied polymer science now are focussing on modelling, simulation, robotics, and expert systems rather than on the traditional subject of laboratory instrument automation and data reduction. The availability of inexpensive computing power and of package software for many applications has allowed the scientist to develop sophisticated applications in many areas without the need for extensive program development. 

A general method has been developed for the estimation of model parameters from experimental observations when the model relating the parameters and input variables to the output responses is a Monte Carlo simulation. The method provides point estimates as well as joint probability regions of the parameters. In comparison to methods based on analytical models, this approach can prove to be more flexible and gives the investigator a more quantitative insight into the effects of parameter values on the model. The parameter estimation technique has been applied to three examples in polymer science, all of which concern sequence distributions in polymer chains. The first is the estimation of binary reactivity ratios for the terminal or Mayo-Lewis copolymerization model from both composition and sequence distribution data. Next a procedure for discriminating between the penultimate and the terminal copolymerization models on the basis of sequence distribution data is described. Finally, the estimation of a parameter required to model the epimerization of isotactic polystyrene is discussed. 

We have presented applications of a parameter estimation technique based on Monte Carlo simulation to problems in polymer science involving sequence distribution data. In comparison to approaches involving analytic functions, Monte Carlo simulation often leads to a simpler solution of a model particularly when the process being modelled involves a prominent stochastic coit onent. 

This review has shown that the analogy between P=C and C=C bonds can indeed be extended to polymer chemistry. Two of the most common uses for C=C bonds in polymer science have successfully been applied to P=C bonds. In particular, the addition polymerization of phosphaalkenes affords functional poly(methylenephosphine)s the first examples of macromolecules with alternating phosphorus and carbon atoms. The chemical functionality of the phosphine center may lead to applications in areas such as polymer-supported catalysis. In addition, the first n-conjugated phosphorus analogs of poly(p-phenylenevinylene) have been prepared. Comparison of the electronic properties of the polymers with molecular model compounds is consistent with some degree of n-conjugation in the polymer backbone. 

What is clear is that the overall strategy, in which the computationally intensive equilibration is performed with a model that does not have atomistic detail, but which can nevertheless be unambiguously identified with a specific real system with atomistic detail, markedly increases the utility of simulations for polymer science. It provides access to much larger systems, and to phenomena that occur on much longer time scales than could be investigated with simulations in which full atomistic detail is retained throughout. 

Rehahn M, Mattice WL, Suter UW (1997) Rotational isomeric state models in macromolecular systems. In Advances in Polymer Science, Springer, Berlin... 

Microcomputers, introduced in the late 1970 s have revolutionized the use of computers. The availability of easy-to-use, inexpensive softwares has also contributed to the upsurge in computer usage. Small systems, with compute power and capability equivalent to large multimillion dollar main frames, are now affordable by small organizations as well as individuals. In this paper the use of computers in applied polymer science will be introduced, using successful applications in our own laboratory as examples. The emphasis is on the application of mathematical modelling and computer simulation techniques. 

A fascinating insight into the impact that modelling can make in polymer science is provided in an article by Miiller-Plathe and co-workers [136]. They summarise work in two areas of experimental study, the first involves positron annihilation studies as a technique for the measurement of free volume in polymers, and the second is the use of MD as a tool for aiding the interpretation of NMR data. In the first example they show how the previous assumptions about spherical cavities representing free volume must be questioned. Indeed, they show that the assumptions of a spherical cavity lead to a systematic underestimate of the volume for a given lifetime, and that it is unable to account for the distribution of lifetimes observed for a given volume of cavity. The NMR example is a wonderful illustration of the impact of a simple model with the correct physics. 

Crystallization in polymers has long been one of the most difficult problems in polymer science. It was to our great surprise that the computer simulations proved very useful in studying this historical problem, if we properly devised the molecular models and the crystallization conditions. But I am aware that there are many problems in the present simulation. Major criticisms will be why the crystallization is so fast, what kind of relevance the present model has to real polymer systems, and how we can bridge the space and time gaps between the present model and real polymers. 

Giannelis, E.P., Krishnamoorthy, R. and Manias, E. (1999) Polymer-silicate nanocomposites Model systems for confined polymers and polymer brushes. Advances in Polymer Science, 138, 107-147. 

The symposium was planned as a state-of-the-art meeting, focusing on the basic science. Program areas included high heat polymers, fire performance of polymers, hazard modeling, mechanism of flammability and fire retardation, char formation, effects of surfaces on flammability, smoke assessment and formation mechanisms, and combustion product toxicity. 

As discussed earlier, the usefulness of the food polymer science approach to the study of water dynamics in foods has been widely demonstrated by numerous researchers studying both model and real food systems. Along with the success of the approach, there still exist a number of areas of concern that need to be mentioned. 

---