Solid epoxy resins

Figure 2.7 Thermal conductivity versus volume concentration of metallic particles of an epoxy resin. Solid lines represent predictions using Maxwell and Knappe models.

The same approach was used by Brzozowski et al. [45] for synthesis of elevated-molecular-weight (E-M) epoxy resins (solid epoxy resins) with reduced flammabil-... 

Figure 12.29. Relative permeability to water of a glass-sphere-filled epoxy resin. Solid line represents equation (12.35) and dashed line experimental data taken at 85°C. Similar decreases below the predicted value were noted at other temperatures as well. (Manson and Chiu, 1973u.)...

The synthesis of elevated-molecular-weight (E-M) epoxy resins (solid epoxy resins) based on polyaddition of bisphenol-A and lower-molecular-weight (L-M) epoxy resin under microwave irradiation was recently described [117]. Usually, E-M epoxy resins are manufactured by the melt process in which liquid epoxy resins and organic compounds that contain two active hydrogen atoms (e.g., bisphenol... 

Solid epoxy resins based on the reaction product of epichlorohydrin and bisphenol A or bisphenol F mild to moderate irritants and mild sensitizers not readily absorbed through skin low volatility, exposure unlikely unless crushed or ground low toxicity... 

The materials of construction, from the cupboard to the fan, should be inorganic and resistant to attack by perchloric acid. For the cupboard itself suitable materials include stainless steel of types, 316 or 317, solid epoxy resin, and rigid PVC. Stainless steel has been popular for this application as it is easy to form, weld, and polish. It is, however, attacked by the acid, which causes discoloration of the metal surface and the formation of iron(III) perchlorate, which can be explosive. Ductwork, separate from other extract systems, is usually made from stainless steel or plastic materials. Fire regulations may preclude the use of plastic ductwork or require it to be sheathed in an outer casing of metal or GRP. The fan casing and impeller can both be made of plastic. 

Bisphenol A is a solid material in the form of white flakes, insoluble in water but soluble in alcohols. As a phenolic compound, it reacts with strong alkaline solutions. Bisphenol A is an important monomer for producing epoxy resins, polycarbonates, and polysulfones. It is produced by the condensation reaction of acetone and phenol in the presence of HCI. (See Chapter 10, p. 273)... 

Two-pack epoxies These were first patented in 1938 but were not in general production until 1947. They have been very widely used over the last decade. Produced from the by-products of the petroleum industry, the basic epoxy resins may be in the form of relatively low-viscosity liquid resins or they may be solid resins of increasing hardness. Both solid and liquid resins can then be reacted with a number of different curing agents. This means that almost any type of film and with any required properties can be made. 

Proppants are solid particles used to hold open the fracture after conclusion of the well treatment. Criteria to choose the economically most effective proppant for a given set of formation conditions have been discussed (7 6). While sand is the most commonly used proppant because of its low cost, resin-coated sand, sintered bauxite, and A O particles have also been used because of their greater compressive strength and resistance to dissolution at high temperature and pH (55). While epoxy resins are most commonly used, the use of other resins such as phenol-formaldehyde has been described. 

Coatings industries processes, air pollution from, 20 106-109 Coatings industry, 9 153 solid epoxy resins in, 10 359 Coating structures, in photography,... 

Instead or bisphenol-A, many other compounds with hydroxyl groups (such as glycols, glycerols and resorcinols) can also be used. The epoxy resins obtained through these reactions will be either highly viscous liquids or solids with high Melting points. 

Macroelectrodes with solid membranes contain homogeneous [142] or heterogeneous [25] membranes. The construction of an ISE of this type with an internal reference electrode is shown in fig. 4.1. For good functioning of an ISE it is necessary that the membrane be completely sealed in the electrode body, with no cracks leading to short-circuiting between the external and internal solutions. Cements based on Teflon, PVC or epoxy resin are used (170). 

Uncured resins are oligomers of relatively low molecular weight that may be a liquid or a solid. Before epoxy resins can become useful products, they must be cured, with the addition of a curing agent. Curing involves the cross-linkage by polymerization of the reactive epoxy groups into a three-dimensional matrix. 

Results are presented of experiments undertaken by Gaiker in the manufacture of sandwich panels containing foam cores based on PETP recycled by a solid state polyaddition process developed by M G Ricerche. Panels were produced with glass fibre-reinforced unsaturated polyester and epoxy resin skins, and allthermoplastic panels with PE, PP, PS and glass fibre-reinforced PETP skins were also produced. EVA hot melt adhesives and thermoset adhesives were evaluated in bonding glass fibre-reinforced PETP skins to the foam cores. Data are presented for the mechanical properties of the structures studied. 

Latexes are usually copolymer systems of two or more monomers, and their total solids content, including polymers, emulsifiers, stabilizers etc. is 40-50% by mass. Most commercially available polymer latexes are based on elastomeric and thermoplastic polymers which form continuous polymer films when dried [88]. The major types of latexes include styrene-butadiene rubber (SBR), ethylene vinyl acetate (EVA), polyacrylic ester (PAE) and epoxy resin (EP) which are available both as emulsions and redispersible powders. They are widely used for bridge deck overlays and patching, as adhesives, and integral waterproofers. A brief description of the main types in current use is as follows [87]. 

Liquid polymers with terminal mercapto groups (LP-2) are obtained when solid polyolefin poiysulfides are reduced. These liquid polymers may be oxidized to solid polymers in the presence of oxidizing agents, such as lead oxides. The liquid polymers are used in caulking compositions and as reactive flexibilizing agents in epoxy resins. 

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