Formulation epoxy resin

An epoxy resin formulation completely free of organic solvent was applied to carbon steel coupons using supercritical carbon dioxide (CO2) as the volatile solvent. Sleet coupons coated in this manner were compared to coupons coated with a standard military specification marine primer (MlL-P-24441) during exposure to aerated 0.5 nrl sodium chloride (NaCl). The solvent-free coating protected the steel from corrosion in this environment as well, if not better than, the solvent-based primer (Kendig et al., 1999). 

The Epoxy Resin Formulators TrainingManual, The Society of Plastics Industry, Inc., New York, 1984. 

Over the past several decades, significant advances have been made in developing epoxy-based adhesives having improved performance over these early adhesive systems. These improvements were made possible by (1) the incorporation of toughening additives into epoxy resin formulations and (2) the use of multifunctional epoxy resins primarily for high-temperature applications. These innovations are discussed in later chapters. 

TABLE 4.4 Properties of an Epoxy Resin Formulation Based on a Blend of Polyglycol Diepoxy Flexibilized Resin and Standard DGEBA Resin, Cured with Methylene Dianiline5... 

Glycidyl ethers of aliphatic polyols based on polyglycol, glycerin, and other polyols are flexible epoxy resins. They are used as reactive diluents and flexibihzers for solvent-free epoxy resin formulations. Epoxy-polyglycol resins that are produced from the reaction of epichlorohydrin and polyester polyols based on ethylene or propylene oxide are the most common of these types of flexible epoxy resins. Examples of typical commercial aliphatic epoxy resins are shown in App. C. 

Buehner, R. W., and Atzinger, G. D., Waterborne Epoxy Dispersions in Adhesive Applications, Epoxy Resin Formulators Conference, San Francisco, February 20-22, 1991. 

Epoxy resin formulations containing aliphatic amines will blush and provide an oily surface under very humid conditions. This is due to a reaction of the amine primary hydrogen atoms with carbon dioxide. Resistance to blushing is more important for coatings than for... 

TABLE 5.4 Surface Tension of Several Epoxy Resin Formulations... 

Diluents are higher-MW components than solvents that are also added to the epoxy adhesive formulation to lower the viscosity and modify processing conditions. The primary function of a diluent in an epoxy resin formulation is to reduce its viscosity to make it easier to compound with fillers, to improve filler loading capacity, or to improve application properties. Solvents, certain curing agents, and flexibilized epoxy resins can also lower the viscosity of epoxy adhesive formulations, but this is not their primary function. The effect of various diluents on the initial viscosity of a diglycidyl ether of bisphenol A (DGEBA) epoxy resin is illustrated in Fig. 6.3. 

By adding flexible diluents to the base epoxy resin formulation... 

Core-shell structures (Fig. 8.7) have also been suggested as a method of toughening epoxy resin formulations. The polymeric shell, which surrounds an elastomeric core, provides good adhesion to the epoxy matrix. Hyperbranched polymers with hydroxyl... 

Chemical manufacturers, formulators, and distributors must make health, safety, and environmental protection an integral part of the product. Several guides have been created to help develop and implement policies and practices that ensure protection through the product life cycle. One of these, developed by the Epoxy Resin Formulators Group of the Society of Plastics Industry, has been found to be most useful for the epoxy formulator.6... 

Product Stewardship Guide, Epoxy Resin Formulators Group, The Society of the Plastics Industry, New York, 2001. 

The properties of thermosetting and thermoplastic resin systems are continually improved to meet increasing performance requirements of end users. One way to enhance material properties is to incorporate nano-modifiers, based on elastomeric silicone particles, which are optionally grafted with other (acrylic) polymers to control dispersibility, viscosity, and other parameters. As an example, epoxy resin formulations have been modified with silicone nanospheres to improve low-stress behavior. Table 1 shows the outstanding fracture toughness improvement of silicone coreshell nanospheres, even at very low particle loading levels. 

Polystyrene-Epoxy Syntactic Foam. Hollow polystyrene microspheres are produced by heating expandable polystyrene (in other words gas-filled spheres, e.g., propane or butane-filled polystyrene) of microscopic size. The expandable polystyrene microspheres may be added to the epoxy-resin formulation, and the exothermic heat (or the heat during oven cure) can be employed for the expansion. In this manner, foams having densities as low as 80 kg/m (5 Ib/ft ) may be developed. 

Tetrabromobisphenol A (TBBPA) is primarily used as a reactive flame retardant in epoxy resin circuit boards. Both hydroxyl groups on TBBPA can be reacted with epichlorohydrin under basic conditions to form the diglycidyl ether, which is widely used in epoxy resin formulations. TBBPA is also used in polycarbonate and ether polyester resins and is used as a chemical intermediate for the synthesis of tetrabromobisphenol A allyl ether, -bis(2-hydroxyethyl ether), -carbonate oligomer, and -diglycidyl ether. TBBA is also used as a flame retardant in plastics, paper, and textiles, and as a plasticizer in adhesives and coatings. 

Coilife [Westinghouse]. TM for special epoxy resin encapsulation of random-wound stators using solventless epoxy-resin formulations and rotational seasoning. 

The commercially available phenoxy resin has Mw around 50,000 and little epoxy functionality. The phenoxy polymer is then classified as a polyol or a po-ly(hydroxy ether) [3]. Typical applications for the phenoxy resin are as hot-melt adhesives, coatings for beverage cans, and toughening agents for various epoxy resin formulations. The viscoelastic properties of phenoxy resins have been studied by Alegria et al. [11-15]. The phenoxy polymer can be used as a reference in the viscoelastic study of DGEBA oligomer. 

Hedreul et al. (1998) examined a model of the cure kinetics of a thermally and microwave-cured rubber-modified epoxy-resin formulation. The phenomenological cure kinetic model used was... 

By lowering the volume percent of resin and increasing the volume percent of the filler, the composite CTE is reduced. This is best illustrated in Figure 3.17 where an epoxy resin formulated with 15 phr of m-phenylenediamine has a CTE of 50 ppm/°C without filler. The addition of about 60% by weight of alumina, for example, lowered the CTE to about 25 ppm/°C. 

K Street NW, Suite 600 Washington DC 20006-1301 Phone (202) 974-5200 (formerly Epoxy Resin Formulators)... 

For such critical applications, moisture uptake at high humidities can lead to changes in physical properties that are vitally important, especially as service temperatures varying between -30°C and +110°C can be encountered. Much study has been devoted to this (e.g. Wright [32] and Eckstein [33]). Water diffuses into even the most resistant resin, especially if the surface is damaged by weathering. It both plasticizes and swells the resin and reduces the bond between it and the reinforcement. For conventional epoxy resins, for each 1 % water pickup, decreases by about 20°C [32,35]. Eckstein [33] examined 70 different epoxy resin formulations and found... 

Kar Karger-Kocsis, J., Gryshchuk, O., lost, N. Toughness response of vinylester/epoxy-based thermosets of interpenetrating network structure as a function of the epoxy resin formulation Effects of the cyclohexylene linkage. J. Appl. Polym. Sci. 88 (2003) 2124—2131. 

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