Chemical linkages

Generation of chemical linkages between long-chain molecules can be compared to two straight chains joined together by links. The rigidity of the material increases with the number of links. The function of a monomer is to provide these links. 

To introduce some interfacial physico-chemical linkage between EVA and PRP, blends were made by adding different quantities of M AH-PP. Some results are demonstrated in Table 12, The physico-mechanical properties of the PRP-EVA compositions modified with MAH-PP showed that properties are influenced by MAH-PP concentration. Compositions with better impact strength and improved brittleness can be prepared by varying the modifier concentration. Tensile strength and elongation are not significantly influenced by the addition of a modifier. An increase in the modifier con-... 

It has been well established that wear resistance of filled rubber is essentially determined by filler loading, filler morphology, and polymer-filler interaction. For fillers having similar morphologies, an increase in polymer-filler interaction, either through enhancement of physical adsorption of polymer chains on the filler surface, or via creation of chemical linkages between filler and polymer, is crucial to the enhancement of wear resistance. In addition, filler dispersion is also essential as it is directly related to the contact area of polymer with filler, hence polymer-filler interaction. 

The vital processes—eg, synthetic reactions, muscular contraction, nerve impulse conduction, and active transport—obtain energy by chemical linkage, or coupling, to oxidative reactions. In its simplest form, this type of coupling may be represented as shown in Figure 10—1. The conversion of metabolite A to metabolite B... 

Another way of immobilizing catalyst complexes might be to trap them in the pores of solid particles, for instance by synthesizing the complex inside the pores of a zeolite ( ship in a bottle ). Another method could be to trap catalyst complexes in porous materials and deposit a membrane at the outer. surface. These methods of immobilizing a homogeneous catalyst do not involve chemical linkage between the catalyst and the carrier. The fixation is the result of steric hindrance. 

The support for a chemical linkage between cellulose and lignin in wood, presented by Hibbert and co-workers (90), is based on their treatment of oak wood with acetic anhydride, glacial acetic acid and catalytic amounts of sulfuric acid. A fraction soluble in dioxane was found to have, after several precipitations, the same composition of lignin, cellulose and pentosan as that of the wood itself. 

Phillips (91) extracted different amounts of lignin from corncobs by altering the concentration of alkali and the temperature of extraction. This was taken by him as evidence in favor of a chemical linkage between the lignin and the carbohydrate. 

Prepare a set of potential binding elements with a common chemical linkage group X... 

Polyamides, polyethers is based on the common chemical linkages found in these polymers. Classification Based on the Mode of Synthesis of Polymers... 

A few of the many chemical linkages or groups that can be detected in polymer spectra, along with the approximate wavelengths at which they occur are shown in figure below. The infrared absorption bands of interest in common polymers are... 

The chemical linkage,, between A and B shown above can be of any sort, provided modification of the physical and chemical processes of excited states occurs when photoactive components form part of a supramolecular structure. 

Considering that the phosphodiester bond is one of the most stable chemical linkages in nature, its cleavage is an obvious and challenging target for antibody catalysis. In an attempt to model a metal-independent mechanism, a... 

Whilst C—H bonds represent the most ubiquitous chemical linkage in Nature, they are at the same time some of the most difficult bonds to cleave, although they are not completely inert [5b,c]. For example, in 1963 Kleinman and Dubeck reported the possibility of C—H bond cleavage in azobenzene by the Cp2Ni complex (Scheme 13.1) [1]. The structure originally proposed by Kleinman and Dubeck considered the nickel center to be coordinated T 2 to the N=N n-bond (2) (Scheme 13.2). 

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