Epoxy base, preparation

Other modifications of the polyamines include limited addition of alkylene oxide to yield the corresponding hydroxyalkyl derivatives (225) and cyanoethylation of DETA or TETA, usuaHy by reaction with acrylonitrile [107-13-1/, to give derivatives providing longer pot Hfe and better wetting of glass (226). Also included are ketimines, made by the reaction of EDA with acetone for example. These derivatives can also be hydrogenated, as in the case of the equimolar adducts of DETA and methyl isobutyl ketone [108-10-1] or methyl isoamyl ketone [110-12-3] (221 or used as is to provide moisture cure performance. Mannich bases prepared from a phenol, formaldehyde and a polyamine are also used, such as the hardener prepared from cresol, DETA, and formaldehyde (228). Other modifications of polyamines for use as epoxy hardeners include reaction with aldehydes (229), epoxidized fatty nitriles (230), aromatic monoisocyanates (231), or propylene sulfide [1072-43-1] (232). 

Literature search shows that epoxy-based nanocomposites have been prepared by many researchers [34-38]. Becker et al. have prepared nanocomposites based on various high-functionahty epoxies. The mechanical, thermal, and morphological properties were also investigated thoroughly [39 3]. The cure characteristics, effects of various compatibilizers, thermodynamic properties, and preparation methods [16,17,44 9] have also been reported. ENR contains a reactive epoxy group. ENR-organoclay nanocomposites were investigated by Teh et al. [50-52]. 

A wide range of paints and other organic coatings is used for the protection of mild steel structures. Paints are used mainly for protection from atmospheric corrosion. Special chemically resistant paints have been developed for use on chemical process equipment. Chlorinated rubber paints and epoxy-based paints are used. In the application of paints and other coatings, good surface preparation is essential to ensure good adhesion of the paint film or coating. 

Flow sheets for preparing the components of various monomer and oligomer reactant mixtures do not differ significantly from each other, although they may have different sets of reactors. The choice depends mainly on the physical and chemical properties of the initial components. Fig. 4.2 shows a flow sheet for obtaining continuously molded polyurethane elastomers. Fig. 4.3 illustrates an elementary flow sheet for a batch process unit for manufacturing moldings of epoxy resin or epoxy-based composites filled with quartz sand. 

Polyindanebisphenol, (III), thermosetting polymers were prepared by McCarthy [3] and were characterized as having a low dielectric constant, low moisture absorption, and a low coefficient of expansion. These materials were used in the production of epoxy-based laminates. 

Cyclic derivatives of type III include cyclic Mannich bases, such as dihydroben-zoxazines 497, employed as detergents for lubricating oils, - and cyclic urcides 498, precursors of crosslinking agents for fabrics, as well as other cyclic derivatives prepared by conversion of Mannich bases. Macromolecular derivatives of type IV are relatively small in size and have branched (star-shaped) structures they are of considerable importance as, for example, corrosion inhibitors 499, plastics stabilizers 500, - pre-polymers for epoxy-based electrophoretic paints, and polyols in polyurethane synthesis. ... 

Two-component IPN foams consisting of polyurethane and epoxy were prepared by the one-shot, free-rise method. The effects of PU/E ratio on the sound absorption and mechanical energy attenuation characteristics were determined with varying levels of different fillers and plasticizers. The formulations (Table IX) were based on the best elastomer results. An average of over 90X absorption was obtained at high frequencies by the Impedance tube method. However, this average drops dramatically at low frequencies. This reduction may be seen in Figs. 3 and 4 for 90/10 and 70/30 IPN foams vlth 20X... 

History The first commercial epoxies were prepared in 1927 in the USA by reacting epichlorohydrin with bisphenol A. The name epoxy is based on the Greek words epi, which means upon and oxy, which means sharp/acidic. 

Dense three-dimensional networks have been prepared by thermal,5-7 photochemical, or sol-gel reactions. From our previous report on a typical thermally crosslinked epoxy-based polymer,7 doping with a crosslinkable dye, though lowered the Tg of the polymer, resulted in a dramatic enhancement of the temporal stability as a direct result of the increased crosslinking density. Nevertheless, polymers which possess high Tg as well as high crosslinking density still exhibit slow decay of the NLO properties at elevated temperatures. 

This full IPN combines the network of an NLO active epoxy-based polymer and the network of an NLO active phenoxy-silicon polymer. l The epoxy-based NLO network is prepared from the epoxy prepolymer (BPAZO) based on the diglycidyl ether of bisphenol A and 4-(4 -nitrophenylazo)aniline functionalized with crosslinkable acryloyl groups. The second NLO network of a phenoxy-silicon polymer is based on an alkoxysilane dye (ASD) of (3-glycidoxypropyl)trimethoxysilane and 4(4 -nitrophenylazo)aniline, and the multifunctional phenoxyl molecule 1,1,1- tris(4-hydroxyphenyl)ethane (THPE).22 Figure 4 shows the chemical structures of BPAZO, ASD, and THPE. Each network can be formed... 

Figure 5.1. Chemical structure and synthetic route of some epoxy-based azo polymers prepared by the postpolymerization azo coupling reaction.

Electrostatic layer-by-layer (LBL) self-assembly techniques based on oppositely charged poipelectrolytes can be useful to create stable noncentrosymmetric order in thin films. Using this interesting technique, thermodynamically stable noncentrosymmetric multilayer films can be prepared without any need for poling. Tripathy et al. reported the fabrication stable multilayer films of epoxy-based side chain azo polymers for second-order nonlinear optics.The second-order NLO coefficients of the five-bilayer LBL films of these polymers were found to be comparable to those of spin-coated poled films. A schematic view of the procedure to fabricate polyelectrolyte-based LBL films is shown in Fig. 7. 

Zhang Y, Fei X, Zhang G, Li H, Shao K, Zhu J, Zhao C, Liu Z, Han M, Na H (2010) Preparation and properties of epoxy-based cross-linked sulfonated poly(arylene ether ketone) proton exchange membrane for direct methanol fuel cell applications, bit J Hydrogen Energ 35 6409-6417... 

Monoglyceride or fatty amide diol of a vegetable oil is initially prepared using the same procedure as described in an earlier chapter (Chapter 4). This diol has to be used as a partial replacement for poly/diols in the preparation of epoxy resin, as 100% epoxies based on this type of diol have been found to have poor performance. A general laboratory procedure with partial oil-based diol is described below. 

How are vegetable oil-based diglycidyl ether type epoxy resins prepared ... 

Requirements of the adhesive. A full compliance spectrum for steel/concrete bonding has been published by the authors(18) and is reproduced as an Appendix at the end of the book. The purpose of the adhesive is to produce a continuous bond between steel and concrete to ensure that full composite action is developed by the transfer of shear stress across the thickness of the adhesive layer. Experience has shown that the best chance of success is likely to be achieved by using cold-cure epoxy based adhesives which have been specially developed for use in the construction industry. Provided that the surfaces have been prepared properly, these bond well to both steel and concrete and do not suffer shrinkage and cracking problems such as may occur with other systems like polyesters. For these purposes a cold-cure adhesive is defined as one which is capable of curing to the required strength between the... 

Fillers and thixotropic agents are used widely throughout the various acrylic sealant and adhesive products. Fillers also form a significant component of epoxy-based adhesives. For example, if it is necessary to identify the filler used in the hardener component of an epoxy product, the isolation sequence involves initial centrifugation of the product to isolate the crude filler component. The latter is then washed repeatedly with acetone and dried thoroughly. The fine dry powder may then be used to prepare a standard KBr disk for IR analysis. 

Kobayashi M, Salto H, Boury B, Matsukawa K, Sugahara Y (2013) Epoxy-based hybrids using T102 nanoparticles prepared via a non-hydrolytic sol-gel route. Appl Organometal... 

The patent literature indicates that the S3uithesis of epoxy compoimds was discovered as early as the late 1890s (2). In 1934, Schlack of I.G. Farbenindustrie AG in Germany filed a patent application for the preparation of reaction products of amines with epoxies, including one epoxy based on bisphenol A and epichlorohy-drin (3). However, the commercial possibilities for epoxy resins were only recognized a few years later, simultaneously and independently, by the DeTrey Freres Co. in Switzerland (4) and by the DeVoe and Raynolds Co. (5) in the United States. 

Electrodeposition processes using epoxy-based automotive primers were developed for anodic and cathodic systems. Anodic systems (AED) employ carboxy-lated epoxy resins neutralized with an amine. A typical binder is prepared by the esterification of the terminal epoxy groups of a solid resin (EEW = 500) with stoichiometric quantities of dimethylolpropionic acid to form a hydroxyl-rich resin. This intermediate is subseqnently treated with a cyclic anhydride to form an acid functionalised polymer, which is then neutralized with the amine. 

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