Constructing Structure-Property-Relationship

Polymer microstructural characterization provides information that is essential to understand polymerization mechanisms and to construct structure-property relationships required for the production of polymers with a set of well-defined molecular and macroscopic properties. 

Toropov AA, Toropova AP, Mukhamedzhanova D, Gutman I (2005a) Simplified molecular input line entry system (SMILES) as an alternative for constructing quantitative structure-property relationships (QSPR). Indian J. Chem. Sect A. 44 1545-1552. 

The combination of CLP techniques and high-throughput experimentation tools accelerates the research in this field significantly. Besides, on the data collected, the construction of 3D-plots and extensive databases will provide the basis for deeper understanding of the underlying principles. As a consequence, the elucidation of quantitative structure-property relationships will be feasible. 

Corma, A Serra, J.M., Serna, P. and Moliner, M. (2005) Integrating high-throughput characterization into combinatorial heterogeneous catalysis unsupervised construction of quantitative structure/property relationship models. /. Catal., 232, 335. 

Currently, there is growing interest in polymers the frameworks of which are constructed from the Group 14 elements silicon, germanium and tin. Several reviews on polysilanes have appeared in the literature . In the first section of this article we focus on recent developments in the chemistry of polygermanes and polystannanes. The chemistry and structure-property relationship of oligostannanes and low molecular weight polystannanes was the subject of earlier reviews . ... 

Food polymers and the behaviour of their mixtures are mainly responsible for the structure-properties relationship in both food and chyme. The two basic features of food are that its biopolymers, proteins and polysaccharides are its main construction materials and water is the main medium, solvent and plasticizer. In other words, three components— protein, polysaccharide and water—are the main elements of food structure that are principally responsible for quality of foods (see also Chapter 13). 

By a quantitative structure-property relationship (QSPR) analysis of a total of 45 different empirical solvent scales and 350 solvents, the direct calculation of predicted values of solvent parameters for any scale and for any previously unmeasured solvent was possible using the CODESS A program [ie. comprehensive descriptors for structural and statistical analysis) developed by Katritzky et al. [244]. The QSPR models for each of the solvent scales were constructed using only theoretical descriptors, derived solely from the molecular solvent structure. This QSPR study enabled classification of the various solvent polarity scales and ultimately allowed a unified PCA treatment of these scales. This PCA treatment, carried out with 40 solvent scales as variables (each having 40 data points for 40 solvents as objects), allowed a rational classification and grouping... 

Abstract In sensor and microfluidic applications, the need is to have an adequate solvent resistance of polymers to prevent degradation of the substrate surface upon deposition of sensor formilations, to prevent contamination of the solvent-containing sensor formulations or contamination of organic liquid reactions in microfluidic channels. Unfortunately, no comprehensive quantitative reference solubility data of unstressed copolymers is available to date. In this study, we evaluate solvent-resistance of several polycarbonate copolymers prepared from the reaction of hydroqui-none (HQ), resorcinol (RS), and bisphenol A (BPA). Our high-throughput polymer evaluation approach permitted the construction of detailed solvent-resistance maps, the development of quantitative structure-property relationships for BPA-HQ-RS copolymers and provided new knowledge for the further development of the polymeric sensor and microfluidic components. 

The results of this work reveal that the general problems, such as "structure-properties" relationships, materials behaviour in different fields, etc. in FGMs, could be in principle solved through the construction and proper solution of integral equations in a scalar form for particular cases. Local fields of stress and strain, temperature, etc. as well as non-steady problems were considered. The approach suggested could be extended on fields of any nature, such as mechanical, concentrational, etc., whereas the form of equations and the method of their solution remain invariant to the kind of problem. 

A new method allowing the prediction of many important physical properties of polymers prior to synthesis was presented in this book. Our quantitative structure-property relationships based on this method enable the prediction of the properties of uncrosslinked isotropic amorphous polymers constructed from nine key elements (carbon, nitrogen, oxygen, hydrogen, fluorine, silicon, sulfur, chlorine and bromine) from which most technologically important synthetic polymers are built. Some properties of crosslinked polymers can also be predicted. 

Model Networks. Construction of model networks allows development of quantitative structure property relationships and provide the ability to test the accuracy of the theories of mbber elasticity (251—254). By definition, model networks have controlled molecular weight between cross-links, controlled cross-link functionality, and controlled molecular weight distribution of cross-linked chains. Silicones cross-linked by either condensation or addition reactions are ideally suited for these studies because all of the above parameters can be controlled. A typical condensation-cure model network consists of an a, CO-polydimethylsiloxanediol, tetraethoxysilane (or alkyltrimethoxysilane), and a tin-cure catalyst (255). A typical addition-cure model is composed of a, co-vinylpolydimethylsiloxane, tetrakis(dimethylsiloxy)silane, and a platinum-cure catalyst (256—258). 

The purpose of this review is to assemble and assess currently available information about structural modification of urea/thiourea inclusion compounds. We concentrate here on the structural aspects of new inclusion compounds with urea/thiourea/selenourea-anion host lattices, most of which were prepared and structurally analyzed in our laboratory. The versatility of urea or thiourea as a key component in the construction of novel anionic host lattices is clearly demonstrated by occurrence of many new types of linkage modes. The results show that co-molecular aggregates of urea or thiourea with other neutral molecules or anionic moieties can be considered as fundamental building blocks for the constructions of various types of novel host lattices. Comments on structure-property relationship for these inclusion compounds are made wherever appropriate. 

Structure-Property Relationships, The studies aimed at construction of the (8 scale and related investigations have uncovered some interesting relationships between indicator structures and solvatochromic effects. It was found (78c, 134) for example, that 4-nitroaniline (1) forms two hydrogen bonds to HBA solvents, that the ratio of the hydrogen bond strengths is about 1.5/1, and that the ratio of the bathochromic spectral effects is 1 /(0.93 0.13). Comparable effects have also been observed with 3-nitroaniline (12). 

Analogous to the construction of quantitative structure-property relationships, mass spectra are mapped onto real numbers by MS descriptors. The values obtained allow us to hnd relationships between mass spectra and structural properties. 

Construction of a Physical Basis for Structure-Property Relationships... 

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