Resins, filled thermosetting

Mineral hydrates, such as alumina trihydrate and magnesium sulfate heptahydrate, are used in highly filled thermoset resins. 

The membrane material used in the past, if a membrane were used at all, was lead. Today membrane materials include rubber, urethanes, fiberglass reinforced thermoset resins, and aggregate filled thermoset resins. The fiberglass reinforced and aggregate filled resins have also found use as linings without brick or tile. 

The filler effects on the chemoviscosity of thermosetting resins have not been studied extensively, but are vital to understanding the rheology of filled thermosets. For example, the effects of filler concentration on viscosity can be used in process control to monitor batch-to-batch variations or to provide essential information for research into alternative filler/resin batches. Ng and Manas-Zloczower (1993) examined an epoxy-resin system with silica filler and established that the elastic modulus of the resin can be expressed in terms of... 

The measurement of yield stress at low shear rates may be necessary for highly filled resins. Doraiswamy et al. (1991) developed the modified Cox-Merz rule and a viscosity model for concentrated suspensions and other materials that exhibit yield stresses. Barnes and Camali (1990) measured yield stress in a Carboxymethylcellulose (CMC) solution and a clay suspension via the use of a vane rheometer, which is treated as a cylindrical bob to monitor steady-shear stress as a function of shear rate. The effects of yield stresses on the rheology of filled polymer systems have been discussed in detail by Metzner (1985) and Malkin and Kulichikin (1991). The appearance of yield stresses in filled thermosets has not been studied extensively. A summary of yield-stress measurements is included in Table 4.6. 

Durez . [OxyQiem/Durez] Phenolic, alkyd, or phthalate resins, some glass or mineral filled thermosets for tqpplics. incl. automrxive transmission parts and braking systems, communication products for compr., transfer, and inj. molding applies. 

Chem. Descrip. y-Methacryloxypropyltrimethoxysilane CAS 2530-85-0 EINECS/ELINCS 219-785-8 Uses Adhesion promoter for adhesives and coatings coupling agent for glass-reinforced and min.-filled thermosetting resins blend additive in resin systems (polyester, acrylic), and filled or reinforced thermoplastic polymers (polyolefins, polyurethanes)... 

Glaskyd Thermoset alkyd resins filled or not, UP American Cyanamid... 

The characteristics of the solution dispersion method are low temperature, small viscosity of solution, and more uniform dispersion. However, this method is used mostly for the preparation of composite material of thermosetting resin filled with whiskers. 

Microcrystalline quartz is obtained by pulverizing quartz sands and is a hard solid (7 Mohs). It increases the thermal shock resistance in brittle resins - some filled thermosetting resins are cracked by relatively few thermal cycles between, say, ambient temperature and 100°C - when added at high concentrations (typically 100-200 parts per hundred by weight). It can be surface treated with an aminosilane to enhance adhesion, when used in epoxy compositions to improve flexural modulus, electrical insulation or thermal properties, and in the case of unsaturated polyesters, it can be treated with a methacrylic silane. 

Other filled resin systems that require a coupling agent include highly filled sand cores with ftiran urea-formaldehyde and urethane resins in the foundry industry highly filled polymer concrete where polyester and epoxy binders are used to bond aggregate and cultured marble, cultured onyx, and cultured granite, where a highly filled thermoset resin is used to bond and aluminum trihydrate. 

The use of conventional organofiinctional silanes, as described in the section on filled thermosetting resins, has been tried in filled thermoplastic resins with mixed results. Oren-ski and co-workers reported good results with the use of Union Carbide A-187 and A-1100 in wollastonite filled engineering resins at high filler loading. Attempts to extend this approach to less reactive thermoplastic resins, such as polyolefins, were less successful. 

Ziemianski, L. P., A Survey of the Effect of Silane Coupling Agents in Various Non-glass Filled Thermosetting Resin Systems, presented at 22nd Annual SPE Conference, Montreal, Canada, Mar. 1966. 

Tang G, Wang Z, Ma Q and Zhao D, Study on improving wear resistance of epoxy resin filled with nanometer alumina . Thermoset Resin 2002 17(1) 4-8 (in Chinese). 

Although it would be desirable to recycle laminate scrap, this has been difficult because of its thermoset nature. However, a 1993 patent (18) suggested a means whereby scrap consisting of cellulose, thermoset resins, and partially reacted resins can be ground to a powder which is used as a filler in a thermoplastic resin. The filled thermoplastic resin is then used for mol ding of various articles. 

Practical methods for synthesis and elucidation of the optimum physical forms were developed at Du Pont (13). The violets fill the void in the color gamut when the inorganics are inadequate. The quinacridones may be used in most resins except polymers such as nylon-6,6, polystyrene, and ABS. They are stable up to 275°C and show excellent weatherabiUty. One use is to shade phthalocyanines to match Indanthrone Blue. In carpeting, the quinacridones are recommended for polypropylene, acrylonitrile, polyester, and nylon-6 filaments. Predispersions in plastici2ers ate used in thermoset polyesters, urethanes, and epoxy resins (14). 

The PAI resin is utilized for small, simple parts. Because of its stiff melt flow, the resin is available in compression moldable powder. Grades include neat, filled, and glass-reinforced resins it is also available in solution for use as an enamel. Because of high prices ( 33—44/kg) the market is limited, estimated at 150—300 tons for the mol ding resin. Resins competing with PAI include PEI, polyethersulfones, and thermoset resins. 

First-generation polymer composites (e.g., fiberglass) used thermosetting epoxy polymers reinforced with randomly oriented short glass fibers. The filled epoxy resin could be cured into a permanent shape in a mold to give lightweight, moderately strong shapes. 

Filament winding, 26 767, 768 of thermosetting resins, 19 558 Filament-winding resin-impregnated glass rovings, 20 117 Filament yarns, 11 250 acrylic, 11 212 Filiform corrosion, 7 174 Filled fibers, encapsulation spinning of, 16 26... 

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