Walnut shell flour

In the past, phenolic mixes were simply a combination of the phenolic resin with a filler such as walnut shell flour or pecan shell flour. These type mixes are still used in some hardwood exterior plywood. Todays phenolic glue mixes for softwood plywood involve mixing phenolic resin with water, filler, extender and sodium hydroxide (usually 50 percent). 

The phenol-formaldehyde resin used as a control adhesive was a commercial resin (control P) characterized previously (0). A second phenolic resin (control C), used once, is reported to have 40.1% nonvolatiles, a viscosity of 0.42 Pa-s, and a specific gravity of 1.180 at 25 °C. Its measured pH was 11. For use, it was mixed with 15% walnut shell flour. 

GlufiL [Agrashell] Walnut shell flour extender/filler. 

Harris, T.C., Georgalas, A., 1981. Cosmetic facial powder containing walnut shell flour. US Patent 4279890. 

Trade Name Synonyms Lipo WSF 35/60 [Lipo http //www.lipochemicals.com] Lipo WSF 60/100 [Lipo http //www.lipochemicals.com] Lipo WSF 60/200 [Induchem AG http //www.induchem.com Lipo http //www.iipochemicals.com] Walnut Shell Flour 40/100 [Fanning http //www. fanncorp. com]... 

Walnut leaf extract Walnut leaves extract. See Walnut (Juglans regia) leaf extract Walnut oil. See Walnut (Juglans regia) oil Walnut Shell Flour 40/100 Walnut shell powder. See Walnut (Juglans regia) shell powder Walocel CRT Walocel CRT-A. See... 

Bark fibers, which would be expected to have a non-polar (ligninlike) surface gave good results when used as a filler in nonpolar thermoplastics. Likewise, peanut hull flour and walnut shell flour, which are rich in phenolic, lignin-like material, are relatively good fillers. Treatment of the surface of rice hull flour to increase its compatability with thermoplastic resins has been shown to greatly enhance its value as a filler. None of the shell flours are fibrous. 

Agrashell, Inc. Tradename for walnut shell flour. Bohemia, Inc. Tradename for fractionated douglas fir bark. 

The usual catalysts or curing agents are ammonium salts, for example ammonium chloride. It may be mixed with wood flour or walnut shell flour and mixed with the amino resin just before application. A buffer may also be included with the catalyst. This could be calcium phosphate. It is slow in reacting but will combine with the acid released by the ammonium chloride and thus reduce the damage that the acid might cause to the wood. Such catalyst systems may be used with urea resins or urea-melamine resins to provide full cure at room temperature for furniture assembly. Resins for plywood and chipboard applications are usually hot pressed without any external catalyst. 

Soybean flour can be used as the main component in adhesive formulations, but it is commonly added as extender for phenolic systems, or blended with casein or other adhesives. They are packaged as dry powders that contain both proteins and carbohydrates. The flour is dispersed in aqueous sodium hydroxide for preparing the adhesive, and also calcium hydroxide is added to extend the open time and to improve water resistance. Soybean glues have a limited water resistance, but recover their strength on drying. They are also susceptible to mold growth, and some fungicides need to be included in the commercial formulations. Fillers are used to reduce cost, but they also lower the performance of the adhesive. Some commonly used fillers are wood and walnut-shell flours, and also clay. 

Among the naturally occurring filler materials are cellulosics, such as wood flour, alpha cellulose, shell flour, and starch, and proteinaceous fillers, such as soybean residues. Approximately 40,000 tons of cellulosic fillers are used annually by the U.S. polymer industry. Wood flour, which is produced by the attrition grinding of wood wastes, is used as a filler for phenolic resins, dark-colored urea resins, polyolefins, and polyvinyl chloride (PVC). Shell flour, which lacks the fibrous structure of wood flour, is made by grinding walnut and peanut shells. It is used as a replacement for wood flour. 

Crude rubber Sugar Cornstarch Pea flour Walnut shells... 

Shellflex371 Shettflex 3211 Shellflex 3271 Shellflex 3681. See Naphthenic oil Shell flour. See Walnut (Juglans regia) shell powder... 

Nutshell flour n. Ground peanut or walnut shells, dried by heating or solvent extraction, have been used as low-cost fillers in olyethy-lene. Physical properties are comparable to those of PE filled with wood flour. 

PROCESSING. At packing houses, those English walnuts to be marketed in the shells (about 40%) are sized, bleached, and bagged for shipment Others are machine-shelled, and the kernels are graded for color and size, and packaged for the retail trade. Some of the poorer grades may be used to make walnut oil and shell flour. 

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