Problems of Polymer Science

The principal problem of polymer science is the mastering of methods for obtaining materials with predetermined properties. Consequently, the main task of polymer chemistry is the development of the methods of synthesis of polymers which exhibit, in principle, any theoretically possible primary structure of macromolecules. At present, many empirical data have been accumulated in the field of experimental chemistry, which in many cases, make it possible to synthesize polymers with a predetermined primary microstructure. In particular, the most interesting in this sense is the available experience of the synthesis of stereoregular polymers. On the whole, the successful fulfilment of this program requires a reasonable and harmonious combination of empirical and theoretical approaches. 

In Chapter 4, the problems of polymer science are brought into line with other systems, well-studied by means of the rigorous methods of statistical jdiysics. Such an interrelation has proved possible due to the principle of universality, whose capabilities are most clearly seen in predicting the properties of polymer systems with such prototypes, which would. seem rather far from polymers, as magnets. 

A. V. Gushchin, V A. Dodonov, paper presented at the International Conference on Fundamental Problems of Polymer Science, Moscow, 1997. 

The discovery of poly-paraxylelene led me to ponder more about various problems of polymer science. I took advantage of my studies of methyl affinitiesto determine the reactivities of various vinyl and diene monomers , and strangely enough the studies of methyl affinities brought me to the discovery of living polymers and to our extensive investigations of anionic polymerization. 

In this section three applications of the parameter estimation technique to problems in polymer science involving sequence distribution data are described. These problems are of varying degrees of difficulty and each serves to point out different aspects of the method. 

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. 

If azimuthal averaging is used for the purpose of isotropization, a geometric problem from the 3D world is taken for a 2D problem57. For the field of polymer science the correct integration procedure has already been described in 1967 by Desper and Stein [148],... 

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. 

A) F. R. Mayo and M. Morton in Unsolved Problems in Polymer Science, National Academy of Science, NRC, Publication No.995, Washington, 1962. 

This paper may be regarded as a sequel to my second book on Cationic Polymerisation [1]. I have aimed here at providing a fairly detailed discussion of some theoretical aspects of the subject which is still (or perhaps now more than ever before) in Dainton s words rudis indigestaque moles (a crude and ill-digested, i.e., confused, mass) [2], I also intend to discuss specifically some of the problems raised by Mayo and Morton in their article Ionic Polymerization in the book Unsolved Problems in Polymer Science [3]. 

M.Kaneko, 11th Symposium on Unsolved Problems of Polymer Chemistry, p.21 The society of Polymer Science, Japan, Tokyo (1976). 

In this review, the problems of complex formation in different systems of interacting macromolecules namely in polymer-polymer, polymer-alternating or statistical copolymer systems are discussed. The influence of solvent nature, the critical phenomena, equilibrium, selectivity and co-operativity in reactions are considered. The perspectives of development of this field of polymer science and the potential practical applications of interpolymer complexes are pointed out. 

On the other hand, for the understanding of the importance of the achievements made in solving specific problems (in our case relating to oligomeric foams) and in the advance of polymer science as a whole, one should use the inductive method. Therefore, this survey is concluded by a discussion of the trends and perspectives of development of all gas-filled polymers. 

The solution of the basic problem of the science of construction materials, namely the establishment of the relationship between structure and properties acquires special complexity for gas-filled polymers. Six levels of structural organization can be distinguished in these materials ... 

As noted above, the first study of the problem of partial chain flexibility has been done by Flory (1) - one more problem in polymer science which he was the first to tackle. Flory has assumed the existence of a favorable arrangement of a number of consecutive base units. The configurational free energy of this arrangement differs by an amount e from other possible sequences. Apparently, these other arrangements do not have to be all identical thus e represents an average value. Flory points out that the stiffness of the chain is involved. He places the chains and solvent molecules on a lattice, a convenient although not a necessary step. 

Many methods for improvements of the spatial resolution in NMR imaging of solid materials have been proposed with different impact on applications in polymer science [8, 9, 11-13, 21]. For the great variety of techniques only those are reviewed in Sections 5.1.3 and 5.1.4 below, which are being applied successfully to problems in polymer science. Depending on the dominating features, the techniques can be classified into frequency and phase encoding approaches. 

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