Polymerization molecular

The first step in the preparation of an LB film is the successful spreading of a monolayer of the material of interest, which may be molecular, polymeric, or particulate and need not be amphiphilic in the traditional sense. This is accomplished by depositing drops of a dilute solution of the material in an appropriate spreading solvent onto the water surface. The concentration is generally millimolar or less, and the solvent selected should be one that will spread across the surface rapidly and evaporate without remaining at the surface or dissolving into the subphase. Common spreading solvents include chloroform, benzene,... 

Schubert M, Yin CH, Castellani M, Bange S, Tam TL, Sellinger A, Horhold HH, Kietzke T, Neher D (2009) Heterojunction topology versus fill factor correlations in novel hybrid small-molecular/polymeric solar cells. J Chem Phys 130 094703... 

It was suggested earlier in this section that oxoacid salts such as CaC03 could be viewed as products of reactions between basic oxides (containing O2- discrete ions) and covalent (molecular/polymeric) oxides in which oxide ions are transferred to form oxo-anions. Analysis of the thermochemistry of such reactions has led to the formulation of a numerical scale of acidity for oxides. In Table 9.1 the acidity parameter a is listed for the most important binary oxides. Highly-negative values indicate a basic oxide, while acidic oxides have positive values. 

Oxygen forms binary compounds with nearly all elements. Most may be prepared by direct reaction, although other methods (such as the thermal decomposition at carbonates or hydroxides) are sometimes more convenient. Oxides may be broadly classified as molecular, polymeric or ionic. 

Classical DFT is an efficient theoretical tool for prediction of microscopic structure, thermodynamics, and phase behavior of bulk and inhomogeneous fluids, both simple (atomic) and molecular (polymeric) (Evans, 1992 Hansen and McDonald, 1986 Wu, 2006 Wu and Li, 2007). The approach has roots in quantum DFT developed by Hohenberg and Kohn... 

A. J. Epstein and J. S. Miller, Molecular Polymeric Magnets Proceedings of the 6th International Conference on Electrical and Related Properties of Organic Solids, Capri, Italy, May 1992 (J. Kalinwski, ed.) Mol. Cryst. Liq. Cryst. (in press). 

There are two mechanisms for the molecular polymerization by disulfide bonds. One is the polymerization through an inter-molecular disulfide bond formed by oxidation between the two free -SH groups located on different protein molecules. The other mechanism is polymerization through an intermolecular disulfide bond formed by an interchange reaction between free -SH groups and disulfide bonds which are located intermolecularly. 

Alcohols react easily with trimethylene ozide in the presence of catalytic amounts (if sulfuric or 7> tolueiiD sulfonic adds to fom the 3-hydroxypropyl ethers.(In addition, some low molecular polymeric... 

Plasma-induced polymerization is essentially conventional (molecular) polymerization that is triggered by a reactive species created in an electric discharge. In order for one to form polymers by plasma-induced polymerization, the starting material must contain polymerizable structures, such as olefinic double bonds, triple bonds, or cyclic structures. 

Oxygen forms binary compounds with nearly all elements. Most may be obtained by direct reaction, although other methods (such as the thermal decomposition of carbonates or hydroxides) are sometimes more convenient (see Topic B6). Oxides may be broadly classified as molecular, polymeric or ionic (see Topics B1 and B2). Covalent oxides are formed with nonmetals, and may contain terminal (E=0) or bridging (E-O-E) oxygen. Especially strong double bonds are formed with C, N and S. Bridging is more common with heavier elements and leads to the formation of many polymeric structures such as Si02 (see Topics FT and F4). 

It can be noted that this reaction Is closely analogous to the free radical inter-intra-molecular polymerization discovered by Butler and Angelo (11) In which a difunctional monomer undergoes such efficient ring closure that a soluble linear polymer is obtained instead of a crosslinked or three-dimensional product. 

The chemical components responsible for the strength properties of wood can theoretically be viewed from three distinct levels the macroscopic (cellular) level, the microscopic (cell wall) level, and the molecular (polymeric) level (i). 

The first reports on supramolecular polymers date back from the pre-Staudinger period, when many researchers were investigating the ways in which aggregates of small molecules could give rise to increased viscosities. It has been suggested that Louis Henry, in 1878, was the first to propose the idea of molecular polymerization by associative interactions, at about the same time that... 

The polymers resulting from plasma polymerizations do not bear simple stochiometric relations to the starting monomers. The plasma polymerization of ethane, C2H6, leads to a polymer with the approximate composition C2H3. Sometimes oils are produced which consist of highly branched oligomers. Films from plasma polymerizations are inevitably cross-linked and insoluble. The term plasma polymerization is thus a misnomer. The plasma polymerization is not a molecular polymerization as, e.g., the addition polymerization of... 

Singer, K. D., Molecular polymeric materials for nonlinear optics, in Polymers for Lightwave and Integrated Optics Technology and Applications (L. A. Homak, ed.), Marcel Dekker, New York, 1992, p. 327. 

Figure 1 schematizes several classes of systems described as SPs. The reference model at the top of the figure represents the classical covalent chain resulting from molecular polymerization of small bifunctional monomers. The covalent chain is an open one, meaning that it could in principle grow to a large DP distribution, irreversible in solution and under a wide range of external variables. 

In view of the presence of the free volume Vf, the macro-molecular polymeric chains still retain a certain degree of freedom of motion that allows for some configurational changes under loads. These changes may be viewed as occurring against viscous resistance and are therefore time dependent. 

Van der Waals forces and many absorption mechanisms are credited in forming surface layers of oiganic substances on the surfaces of fillers. These are used frequently to explain the reinforcing nature of many fillers with special attention to various forms of silica. It is known that the low molecular polymeric fragments are more likely to be involved in these interactions because they are more mobile and they have a higher probability to meet a suitable partner for interaction. It is... 

In spite of the vast difference between molecular and supramolecular polymers, some concepts and questions that are relevant in molecular polymerization need to be considered also in its supramolecular counterpart. In particular, a key question is how large will the degree of linear supramolecular polymerization... 

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