Author: Derrick B. Callander
Publisher:
ISBN:
Category : Chemistry, Technical
Languages : en
Pages :
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Book Description
Free volume and free volume distribution have long been used to explain differences in the gas transport properties of polymeric materials. However, only a few experimental techniques allow a comprehensive evaluation of polymeric void space. Through the use of computer simulations, the free volume was characterized of two polyester systems used for beverage packaging and polynorbornene, a unique polymer with possible applications in both microelectronic fabrication and membrane separations. Delaunay Tessellation was used to calculate the fractional free volume (FFV) of both polyethylene terephthalate (PET) and polyethylene naphthalate (PEN) molecular models. It was hypothesized that differences in the FFV distributions could be used to explain the higher experimental O2 solubility in PEN relative to PET. The analysis showed that there was no statistical difference between the FFV distributions for O2 sized penetrants. Clustering analysis was performed based upon the tetrahedra formed by Delaunay Tessellation to examine the connectivity of free volume pockets. These results show that there is a statistically larger number of small (containing less than 10 tetrahedra/cluster and between 20-30 Å3 in volume) clusters in PEN. It is this difference in small clusters which provides for the 30% higher O2 solubility in PEN. The free volume of a representative high molecular weight amorphous model of Hexafluroalcohol Substituted Polynorbornene (HFA-PNB) was also characterized in to examine the shape of the free volume cavities and to draw correlations with the mean lifetime of ortho-positronium (o-Ps) from Positron Annihilation Lifetime Spectroscopy (PALS). Delaunay Tessellation and clustering analysis indicated that the free volume clusters in high molecular weight HFA-PNB are slightly non-spherical. Correcting lifetimes for the somewhat non-spherical shape of these free volume clusters was insufficient to reproduce experimentally measured positron annihilation lifetimes because the clusters contained many tortuous connections within the clusters. Inclusion of this connectivity information does produce a more accurate estimate of the measured life times. This indicates that the o-Ps does sample many tetrahedra in these static clusters, but does not freely sample every section of these clusters.
Author: Jag J. Singh
Publisher:
ISBN:
Category : Molecular weights
Languages : en
Pages : 16
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Book Description
Author: Jean Louis Halary
Publisher: John Wiley & Sons
ISBN: 0470922885
Category : Technology & Engineering
Languages : en
Pages : 743
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Book Description
Advanced reviews for Polymer Materials "Molecular modeling of polymers ... is a subject that cannot be found in any other [book] in any appreciable detail. ... [T]he detailed chapters on specific polymer systems is a great idea." — Gregory Odegard, Michigan Technological University "The polymer community needs a text book which can connect the macroscopic mechanics with mesoscopic and molecular aspects of polymer." — Liangbin Li, University of Science and Technology of China This book takes a unique, multi-scale approach to the mechanical properties of polymers, covering both the macroscopic and molecular levels unlike any other book on the market. Based on the authors’ extensive research and writing in the field, Polymer Materials emphasizes the relationships between the chemical structure and the mechanical behavior of polymer materials, providing authoritative guidelines for assessing polymer performance under different conditions and the design of new materials. Key features of this book include: Experimental results on selected examples precede and reinforce the development of theoretical features In-depth discussions of a limited number of polymer systems instead of a brief overview of many Self-contained chapters with a summary of their key points Comprehensive problems and a solutions manual for the different parts of the book Coverage of the basics with an emphasis on polymer dynamics An indispensable resource for polymer scientists and students alike, Polymer Materials is also highly useful for material scientists, engineers, chemists, and physicists in industry and academia.
Author: Gregory C. Rutledge
Publisher: John Wiley & Sons
ISBN: 9783527298013
Category : Science
Languages : en
Pages : 134
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Book Description
Author: Purushottam D. Gujrati
Publisher: John Wiley & Sons
ISBN: 9783527630264
Category : Technology & Engineering
Languages : en
Pages : 564
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Book Description
Filling a gap in the literature and all set to become the standard in this field, this monograph begins with a look at computational viscoelastic fluid mechanics and studies of turbulent flows of dilute polymer solutions. It then goes on discuss simulations of nanocomposites, polymerization kinetics, computational approaches for polymers and modeling polyelectrolytes. Further sections deal with tire optimization, irreversible phenomena in polymers, the hydrodynamics of artificial and bacterial flagella as well as modeling and simulation in liquid crystals. The result is invaluable reading for polymer and theoretical chemists, chemists in industry, materials scientists and plastics technologists.
Author: Leszek A. Utracki
Publisher: John Wiley & Sons
ISBN: 0470193425
Category : Technology & Engineering
Languages : en
Pages : 805
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Book Description
Providing a comprehensive review of the state-of-the-art advanced research in the field, Polymer Physics explores the interrelationships among polymer structure, morphology, and physical and mechanical behavior. Featuring contributions from renowned experts, the book covers the basics of important areas in polymer physics while projecting into the future, making it a valuable resource for students and chemists, chemical engineers, materials scientists, and polymer scientists as well as professionals in related industries.
Author: Elizabeth A. Colbourn
Publisher: Longman Publishing Group
ISBN:
Category : Science
Languages : en
Pages : 360
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Book Description
For chemists, physicists, and students of computer simulation, provides a detailed examination of the complex problems of time and size scaling in molecular modeling and simulation. It includes not only atomistic modeling but also coarse-grained models, which allow longer time scales and therefore larger systems to be studied. Monte Carlo methods are also discussed, and have proven to be particularly powerful tools for examining a range of polymer problems. Assumes a background knowledge of synthetic polymer properties and simulation. Annotation copyright by Book News, Inc., Portland, OR
Author: Enrico Drioli
Publisher: Springer
ISBN: 9783662443231
Category : Technology & Engineering
Languages : en
Pages : 1100
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Book Description
A landmark work covering the major aspects of the science, technology and application of membrane operations and related fields, from basic phenomena to the most advanced applications and future perspectives. Over 1500 concise entries in an A-Z format cover a vibrant field with a multitude of applications in diverse disciplines such as biotechnology, medicine, agro-food and petrochemical industries, environmental protection, as well as drinking water supply. Coverage includes membrane reactors and catalytic design (catalytic membrane reactors). Practically all unit operations of process engineering can be redesigned as membrane unit operations (e. g. membrane distillation, membrane crystallization, membrane stripping, membrane scrubbing). Entries are provided by an international team of experts from academia, research institutions as well as from industry.
Author: Michael Lewis Greenfield
Publisher:
ISBN:
Category :
Languages : en
Pages : 576
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Book Description
Author: Michael Kotelyanskii
Publisher: CRC Press
ISBN: 0824751310
Category : Technology & Engineering
Languages : en
Pages : 572
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Book Description
