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Describes families of materials and their properties and provides a student quiz, possible outcomes, sources of information, and a design brief in which students build something using a variety of materials. (SK)

Classroom demonstrations of selected mechanical properties of polymers are described that can be used to make quantitative measurements. Stiffness, strength, and extensibility are mechanical properties used to distinguish one polymer from another. (KR)

Presents some principles for specifying general classes of polymers for predicting relative chemical attack from acids, bases, oxidants, and certain common antagonists. Also discusses predicting relative solvent effects. Suggests uses of this information in two or three lectures in a chemical engineering materials course. (YP)

Discussed are applications of biochemistry. Included are designed drugs, clever drugs, carcinogenic structures, sugary wine, caged chemicals, biomaterials, marine chemistry, biopolymers, prospecting bacteria, and plant chemistry. (CW)

The apparatus, reagents, preliminary classification, nomenclature, acquisition, and procedures used in the identification of synthetic polymers are described. Specific tests for the identification of the presence of hydrocarbons, chlorine, fluorine, sulfur, and nitrogen and the absence of halogens and sulfur are discussed. (CW)

Presented is a classification of polymers according to physical condition. Considered are molecular structure and arrangements. Described are demonstrations using polarized light and the mechanical properties of polymers. (CW)

Describes the history of the human understanding of polymers from alchemy to modern times. Discusses renaissance chemistry, polymers in the nineteenth century, synthetic elastomers, thermoplastic elastomers, fibers, coatings, adhesives, derivatives of natural rubber, thermosets, step-reaction, and chain polymerization. (CW)

Details ab initio crystal orbital calculations using all-trans-polyethylene as a model. Describes calculations based on various forms of translational symmetry. Compares these calculations with ab initio molecular orbital calculations discussed in a preceding article. Discusses three major approximations made in the crystal case. (CW)

In this article, the third part of a series, the results of ab initio polymer calculations presented in part 2 are discussed. The electronic structure of polymers, symmetry properties of band structure, and generalizations are presented. (CW)

Describes several techniques to help students visualize the principles of polymer chemistry. Outlines demonstrations using simple materials (such as pop-it beads, thread, and wire) to illustrate the size of macromolecules, the composition of copolymers, and the concept of molecular mass. (TW)

Discusses the diversity of names used for various types of polymeric materials. Concentrates on the naming of linear organic polymers. Delineates these polymers by discussing common names, source-based names, characteristic group names, and structure-based names. Introduces the specifications of tacticity and geometric isomerism. (TW)

Outlines the chemistry of the rapid synthesis of relatively large DNA fragments (100-200 monomers each) with yields exceeding 99 percent per coupling. DNA synthesis methodologies are outlined and a polymer-supported synthesis of DNA using deoxynucleoside phosphoramidites is described with structural formulas. (YP)

Discusses the physical basis and current understanding of hydrophobic effects. The thermodynamic background of the effects, hydrophobic hydration, and hydrophobic interactions are described. Four existing controversies are outlined. (YP)

Discusses the history and commercialization of alkanes. Examines the nomenclature and uses of alkanes. Studies polymerization and several types of polyethylenes: low-density, high-density, low-molecular-weight, cross-linked, linear low-density, and ultrahigh-molecular-weight. Includes a glossary of hydrocarbon terms. (MVL)

Discusses a symposium which focused on the influence of inorganic chemistry on organic synthesis, the impact of organic chemistry on biochemistry and vice versa, chemical reaction dynamics, and advances in inorganic chemistry. Explains the purpose of the symposium was to illustrate the intellectual dynamism of modern chemistry. (MVL)

Describes two applications of the microcomputer for laboratory exercises. Explores radioactive decay using the Batemen equations on a Macintosh computer. Provides examples and screen dumps of data. Investigates polymer configurations using a Monte Carlo simulation on an IBM personal computer. (MVL)

Reviews four organic chemistry computer programs and three books. Software includes: (1) NMR Simulator 7--for IBM or Macintosh, (2) Nucleic Acid Structure and Synthesis--for IBM, (3) Molecular Design Editor--for Apple II, and (4) Synthetic Adventure--for Apple II and IBM. Book topics include physical chemistry, polymer pioneers, and the basics of chemistry. (MVL)

Considers the applicability of the simple emersion/weight-gain method for predicting diffusion coefficients, solubilities, and permeation rates of chemicals in polymers that do not undergo physical and chemical deterioration. Presents the theoretical background, procedures and typical results related to this activity. (CW)

Discusses trends and issues in polymer chemistry. Includes developments in mechanical, thermal, electrical, and optical behavior. Illustrated are some structures and characteristics of polymers. (CW)

Discusses the Shell Higher Olefins Process (SHOP) in the manufacture of primary C11-C15 fatty alcohols. Offers examples and explanations of the four-step process. Gives uses for reaction products. (ML)

Discusses the production and use of polymer materials as thermal insulators. Lists several materials that provide varying degrees of insulation. Describes the production of polymer foam and focuses on the major applications of polystyrene foam, polyurethane foam, and polyisocyanurate foam. (TW)

Discusses the product of alkenes, including isopropyl alcohol, ethylene, propylene, thermoplastics, and synthetic rubber. The developments and chemical formulas of the products are described. (YP)

Discusses the history and development of Plasma Desorption Mass Spectrometry to determine molecular weights and structures of proteins and polymers. Outlines theory, instrumentation, and sample preparation commonly used. Gives several examples of resulting spectra. (ML)

This review covers methods for identification, characterization, and determination of rubber and materials in rubber. Topics include: general information, nuclear magnetic resonance spectroscopy, infrared spectroscopy, thermal methods, gel permeation chromatography, size exclusion chromatography, analysis related to safety and health, and miscellaneous techniques. (MVL)

Reviews techniques for the characterization and analysis of synthetic polymers, copolymers, and blends. Includes techniques for structure determination, separation, and quantitation of additives and residual monomers; determination of molecular weight; and the study of thermal properties including degradation mechanisms. (MVL)

Proposes a two-stage experimental approach that combines preparative chemistry and polymer characterization. Describes the simple organic synthesis of a plasticizer, the dioctylphthalate, and its direct use in the preparation of a styrene/divinylbenzene network copolymer. Discusses how to evaluate the physical properties of the resulting plastic. (TW)

Describes a polymerization reactor engineering course offered at Michigan Technological University which focuses on the design and operation of industrial polymerization reactors to achieve a desired degree of polymerization and molecular weight distribution. Provides a list of the course topics and assigned readings. (TW)

Lists eight sources of technical information suitable for classroom use which deal with polymer materials. Provides the names and addresses of these societies and associations and describes the type of information each has available. (TW)

Describes two demonstrations (1) a dust explosion using a coffee can, candle, rubber tubing, and cornstarch and (2) forming a silicate-polyvinyl alcohol polymer which can be pressed into plastic sheets or molded. Gives specific instructions. (MVL)

Describes a three-week summer program teaching selected chemistry faculty how to incorporate polymer chemistry into chemistry courses. In addition to lectures, the program conducted many experiments and provided a trip to industry laboratories. (YP)

Discusses a continuing education course that reached 1000 viewers at 43 North American sites. Points out that each professor had 35 minutes for his presentation followed by a 10-minute call-in question and answer period. Notes polymer topics will be the focus of upcoming lessons. (MVL)

Reviews current biochemistry, education, and polymer course options found in chemistry programs. Proposes a new core curriculum with 28 semester hours with courses in inorganic, chemical, and instrumental analysis, organic, bioorganic, and physical chemistry. Notes that the new curriculum would better prepare students for the existing employment areas. (MVL)

Gives a brief account of fluoropolymers as an important part of polymer chemistry and attempts to make the topic relevant to the secondary school audience. Provides general characteristics and applications for fluoropolymers. (MVL)

1H spin–lattice relaxation experiments have been performed for ionic liquid–polymer gel membranes, including 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF4]) and poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP) with different proportions. The experiments have been performed in a broad range of resonance frequencies (from about 5 Hz to 40 MHz) vs temperature and complemented with analogous studies for [BMIM][BF4] in bulk as a reference. A model of the relaxation processes in the membranes has been proposed. The model includes two relaxation contributions. One of them corresponds to the concept of restricted, two-dimensional translation diffusion with a residence lifetime, while the second one has the form characteristic of polymers (mathematically similar to the limiting behavior of two-dimensional translation diffusion with a very long residence lifetime). The extensive dataset has been consistently interpreted in terms of the model, revealing two dynamical processes on the time scales of 10−7 s (for the second relaxation contribution) and 10−9 s (for the first one). The relationship of these relaxation contributions to the motion of the polymer or ionic liquid–polymer complexes and to the translation diffusion of BMIM cations in the matrix has been discussed. [ABSTRACT FROM AUTHOR]

Unlike one-dimensional polymers, the theoretical framework on the behaviors of two-dimensional (2D) polymers is far from completeness. In this study, we model single-layer flexible 2D polymers of different sizes and examine their scaling behaviors in solution, represented by Rg ∼ Lν, where Rg is the radius of gyration and L is the side length of a 2D polymer. We find that the scaling exponent ν is 0.96 for a good solvent and 0.64 for under poor solvent condition. Interestingly, we observe a previously unnoticed phenomenon: under intermediate solvent conditions, the 2D polymer folds to maintain a flat structure, and as L becomes larger, multiple folded structures emerge. We introduce a shape parameter Q to diagram the relationship of folded structures with the polymer size and solvent condition. Theoretically, we explain the folding transitions by the competition between bending and solvophobic free energies. [ABSTRACT FROM AUTHOR]

The dynamical and conformational properties of the comb polymer with various rigidities of the backbone and arms in steady shear flow are studied by using a hybrid mesoscale simulation approach that combines multiparticle collision dynamics with standard molecular dynamics. First, during the process of the comb polymer undergoing periodic tumbling motion, we find that the rigidity of the arms always promotes the tumbling motion of the comb polymer, but the rigidity of the backbone shifts from hindering to promoting it with increasing the rigidity of the arms. In addition, the comb polymer transitions from vorticity tumbling to gradient tumbling with the increase in shear rate. Second, the range of variation of the end-to-end distance of the backbone and the average end-to-end distance of the arms increases with the increase in the rigidity of the arms and backbone, respectively, and the range of both changes grows with the increase in shear rate. Furthermore, as the rigidity increases, the moldability of the comb polymer decreases and the orientation angle of the comb polymer increases. [ABSTRACT FROM AUTHOR]

The modern era of running shoes began in the 1960s with the introduction of simple polymer midsole foams, and it ended in the late 2010s with the introduction of advanced footwear technology (AFT). AFT is characterized by highly compliant, resilient, and lightweight foams with embedded, rigid, longitudinal architecture. This footwear complex improves a runner's efficiency, and it introduced a step change in running performance. Purpose: This review serves to examine the current state of knowledge around AFT—what it is and what we know about its ingredients, what benefits it confers to runners, and what may or may not mediate that benefit. We also discuss the emerging science around AFT being introduced to track-racing spikes and how it is currently regulated in sporting contexts. Conclusions: AFT has changed running as a sport. The construction of AFT is grossly understood, but the nature of the interacting elements is not. The magnitude of the enhancement of a runner's economy and performance has been characterized and modeled, but the nuanced factors that mediate those responses have not. With these knowns and unknowns, we conclude the review by providing a collection of best practices for footwear researchers, advice for runners interested in AFT, and a list of pertinent items for further investigation. [ABSTRACT FROM AUTHOR]