Basic Polymer Properties

J. G. Pritchard, Poly(VinylAlcohol) Basic Properties and Uses, Polymer Monographs, Vol. 4, Gordon Breach, New York, 1970. 

Since one of the main chemical and technological problems of conducting polymers is their low stability for long-term applications, and since storage capacity is a quantification of the basic property of these... 

The spiro polymerization is a novel reaction type that uses the spiro dimerization of o-QMs to build up linear oligomers and polymers. The basic properties of the spiro dimer of a-tocopherol, that is, its fluxional structure and its ready reduction to the ethano-dimer, remain also active when such structural units are bound in the polymer. The products of the reaction, both in its poly(spiro dimeric) form (41) and in the form of the reduced polytocopherols (42), are interesting materials for application as high-capacity antioxidants, polyradical precursors, or organic metals, to name but a few. 

A basic property of all conducting polymers is the conjugation of the chain-linked electroactive monomeric units, that is, the monomers interact via a jt-electron system. In this respect, they are fundamentally different from redox polymers. Although redox polymers also contain electroactive groups, the polymer backbone is not conjugated and the interaction between the isolated redox counters is weak. Consequently, redox polymers are nonconductors [17]. They will not be discussed in this context. 

Basic properties are those of the polymer but foaming reduces some of them. 

In this chapter we will attempt to provide a brief but illustrative description of the various aspects of the research and technology of conducting polymers. To appreciate fully the diverse range of operations that these materials may fulfil, it is crucial to understand their basic properties. Therefore, particular attention will be devoted here to the description of the mechanism of charge transport and to the characteristics of the electrodic processes in electrochemical cells. 

Because of the repulsion of the cyanide groups the polymer backbone assumes a rod-like conformation. The fibers derive their basic properties from this stiff structure of PAN where the nitrile groups are randomly distributed about the backbone rod. Because of strong bonding between the chains, they tend to form bundles. Most acrylic fibers actually contain small amounts of other monomers, such as methyl acrylate and methyl methacrylate. As they are difficult to dye, small amounts of ionic monomers, such as sodium styrene sulfonate, are often added to improve their dyeability. Other monomers are also employed to improve dyeability. These include small amounts (about 4%) of more hydrophilic monomers, such as -vinyl-2-pyrrolidone (Equation 6.69), methacrylic add, or 2-vinylpyridine (Equation 6.70). 

Crystalline polymers exhibit the following basic properties They are opaque as long as the size of the crystallites or spherulites, respectively, lies above the wavelength of light. Their solubility is restricted to few organic solvents at elevated temperature. The following crystalline polymers have attained technical importance as thermoplastic materials polyethylene, polypropylene, aliphatic polyamides, aliphatic/aromatic polyamides, aliphatic/aromatic polyesters, poly-oxymethylene, polytetrafluoroethylene, poly(phenylene sulfide), poly(arylene ether ketone)s. 

Amphoteric a substance that exhibits both acidic and basic properties Amylopectin branched glucose polymer component of starch... 

Carry oxygen and hemoglobin through the arteries, veins, and capillaries of living animals Used in polymer manufacture to create porosity Initiates reactions and accelerates their rate, without being consumed. Usually by means of acidic or basic properties. 

The second article by Kawahara and his coworkers focuses on polyolefin (PO)-based hybrid materials (POH), in view of their synthesis, structures, and properties. POs are currently the most widely and conveniently used polymeric materials as recognized by the production amount of over one hundred million tons annually in the world, due to the cheap price yet good properties. They are basically hydrocarbon polymers, and hence hydrophobic and less polar. These basic properties are to be modified by introducing a polar function for a wider use in practical applications. Preparation of POHs is one of the best ways to... 

It is instructive to compare the basic properties of the piezoelectric polymer, polyvinylidene fluoride (PYDF) with those of PZT . The flexibility and low density of the polymer contrasts with the stiffness, brittleness and high density of PZT . On the other hand the piezoelectric d coefficient for PYDF is relatively small ( — 30pCN the mechanisms by which the polarisation in PVDF... 

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