Structure and properties of macromolecules

Herman Mark is famous for his tremendous contributions to the field of polymer science. He is not so well known for his early work in the field of crystal structure, nevertheless, I think that it was his experience in the crystal structure field that gave him the badkground that permitted him to make his important contributions to the understanding of polymers. He was, in fact, one of the leading investigators in the field of Uie use of x-ray diffraction for the determination of the structure of crystals in the years 1923 to 1928, and it was through this work that he developed the feeling for atoms and their interaction with one another that permitted him, later on, to make an effective attack on the problem of the structure and properties of macromolecules. 

T. Yamamoto, A. Morita, Y. Miyazaki, T. Marayama, H. Wakayama, Z.H. Zhou, Y. Nakamura, T. Kanbara, S. Sasaki, and K. Kubota, Preparation of ir-conjugated poly(thiophene-2,5-diyl), poly(p-phenylene), and related polymers using zerovalent nickel complexes. Linear structure and properties of the TT-conjugated polymers, Macromolecules, 25 1214—1223, 1992. 

Xu J, Fogleman EA, Craig SL. Structure and properties of DNA-hased reversible polymers. Macromolecules 2004 37 1863-1870. 

Kato T, Kihara H, Ujiie S, Uryu T, Frechet JMJ. Structures and properties of supramolecular liquid-crystalline side-chain polymers built through intermolecular hydrogen bonds. Macromolecules 1996 29 8734-8739. 

Abstract Macromolecular coils are deformed in flow, while optically anisotropic parts (and segments) of the macromolecules are oriented by flow, so that polymers and their solutions become optically anisotropic. This is true for a macromolecule whether it is in a viscous liquid or is surrounded by other chains. The optical anisotropy of a system appears to be directly connected with the mean orientation of segments and, thus, it provides the most direct observation of the relaxation of the segments, both in dilute and in concentrated solutions of polymers. The results of the theory for dilute solutions provide an instrument for the investigation of the structure and properties of a macromolecule. In application to very concentrated solutions, the optical anisotropy provides the important means for the investigation of slow relaxation processes. The evidence can be decisive for understanding the mechanism of the relaxation. 

A hierarchy of approximations now exists for calculating interactions between a charged particle and a charged, planar interface in electrolyte solutions. At moderate surface potentials less than approximately 2(kT/e the linear Poisson-Boltzmann equation provides a good approximation in many circumstances, provided the solution is a 1 1 electrolyte at low to moderate ionic strength. The relative simplicity of the linear equation makes it particularly useful for examining problems that are complicated in other ways, such as interactions involving many particles, interactions with deformable interfaces, and interactions where the detailed structure and properties of the particle (or macromolecule) play an important role. 

Questions that had been of fundamental importance to quantum chemistry for many decades were addressed. When the existence of bond alternation in trans-polyacetylene was been demonstrated [14,15], a fundamental issue that dates to the beginnings of quantum chemistry was resolved. The relative importance of the electron-electron and electron-lattice interactions in Ti-electron macromolecules quickly emerged as an issue and continues to be vigorously debated even today. Aspects of the theory of one-dimensional electronic structures were applied to these real systems. The important role of disorder on the electronic structure and properties of these low dimensional metals and semiconductors was immediately evident. The importance of structural relaxation in the excited state (solitons, polarons and bipolarons) quickly emerged. 

Lin CC, Jonnalagadda SV, Kesani PK, Dai HJ, Balsara NP (1994). Macromolecules 27 7769. Lohse DJ, Fetters LJ, Doyle MJ, Wang H-C, Kow C (1993). Macromolecules 26 3444. Lyngaae-Jorgensen J (1985). In Processing Structure and Properties of Block Copolymers, edited by MJ Folkes (ed). Applied Science, New York. 

Over the past decade or so, these remarkable achievements by nature have been recognized by the polymer science community. This has led to an increased interest in the use of biological concepts to synthesize polymers or to control the structure and properties of synthetic polymers. Of particular interest are peptide hybrid polymers. Combining peptide and synthetic polymer segments into a single macromolecule offers interesting possibilities to synergize the properties of the individual components and to compatibilize bio- and synthetic systems. 

Synthetic polypeptides consist of a repeating sequence of certain amino acids and their primary structures are not as complicated as those in proteins. The polypeptides are very important polymers in both polymer and protein science. The characteristic properties related to the structure lead to possible expansion for research in the field of polymer science, to provide very different moplecules from conventional synthetic polymers. For example, the concept of the liquid crystal is expanded by revealing the variety of structures and properties of liquid crystals. Furthermore, the polypeptides are sometimes used as biomimic materials. On the other hand, synthetic polypeptides are sometimes used as model biomolecules for proteins because they take the a-helix, /3-sheet, o)-helix structure, and so on, under appropriate conditions. From such situations, it can be said that synthetic polypeptides are interdisplinary macromolecules and are very important for research work in both polymer and protein science. 

J. R. Flick and S. E. B. Petrie, Studies in Physical and Theoretical Chemistry, 10, 145-163 (1978). (Volume title Structure and Properties of Amorphous Polymers. Edited by A. G. Walton. Contains the Proceedings of the Second Symposium on Macromolecules, held in Cleveland, Ohio, October 31-November 2, 1978). 

Reitzel, N. et al.. Self-assembly of conjugated polymers at the air/water interface. Structure and properties of Langmuir and Langmuir-Blodgett films of amphiphilic regioregular polythiophenes, J. Am. Chem. Soc. 122, 5788-5800, 2000. de Boer, B. et al.. Amphiphilic, regioregular polythiophenes. Macromolecules 35, 6883-6892, 2002. 

Hence, formation of the structure and properties of epoxy polymers during curing is determined by fundamental physical principles. This is accompanied by the change in the characteristic ratio C (molecular characteristics), although the structure of the macromolecule remains invariant. The use of the above physical principles even in the simplest version provides a correct description of the structure and properties of network polymers. 

This book provides an overview of possible combinations of metal complexes and metals with organic and inorganic macromolecules (often also named macromolecular metal complexes — MMC [1]). This book covers the formation, synthesis, structure and properties of these exciting and relatively new materials. Metal-containing macromolecules are a fascinating field of science. It is readily understandable that materials with unusual properties are obtained by having a metal complex or metal as part of a macromolecule. Nature shows us the functions of such materials extremely well by the selectivity and activity of, for example, hemoglobin, photosynthesis and metalloenzymes. 

To clarify the then new chemistry of macromolecules, he spoke of the monomer molecules as the building blocks. When linked together by polymerization these form the structure of the polymer molecule. The size and shape of the building blocks and the way they are arranged in the polymer molecule will affect the structure and properties of the molecules and hence those of the plastics material. Thus the monomer units have the same relationship to the plastic products as building bricks have to a com-... 

S.A. Chen and H.T. Lee, Structure and properties of poly(acrylic acid)-doped polyanihne structure and properties of poly(acrylic acid)-doped polyaniline. Macromolecules, 28, 2858-2866 (1995). 

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