Shell flour

Oxahc acid manufacture via the oxidation of carbohydrates is stiU actively pursued, especially in China (10—12). In India, processes which produce sihca and oxahc acid have been developed (13,14). The raw materials include agricultural wastes, such as rice husks, nut shell flour, com cobs, baggase, straw, etc. 

Another commonly employed low-cost organic filler is coconut shell flour. This can be incorporated into the moulding composition in large quantities and this results in cheaper mixes than when woodflour is used. The mouldings also have a good finish. However, coconut shell flour-filled mouldings have poor mechanical properties and hence the filler is generally used in conjunction with woodflour. 

The adhesive resins are of the novolak type and generally hardened by paraformaldehyde (which may be supplied mixed with coconut shell flour or diatomaceous earth) in conjunction with an accelerator such as magnesium oxide. 

Cellulosic materials, such as wood, in their different forms (i.e., wood flour and wood pulp), cotton, shell flours, ground com cobs, and other vegetable by-products or agro-wastes are used as the source of cellulosic raw materials for the plastic industry [29,56], at least as... 

Among the naturally occurring filler materials are cellulosics such as wood flour, a-cellulose, shell flour, and starch, and proteinaceous fillers such as soybean residues. Approximately 40,000 t 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 filler for phenolic resins, urea resins, polyolefins, and PVC. Shell flour, which lacks the fibrous structure of wood flour, has been used as a replacement for wood flour for some applications. 

Which would yield the stronger composite (a) peanut shell flour, or (b) wood 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). 

In hardwood plywood, the glue mix is typically formed by adding water and soft wheat flour at rather high proportions with a minor addition of filler, such as nut shell flour to the urea-formaldehyde resin. Urea-formaldehyde resins are usually shipped in 60 - 65 percent non-volatile solids form. Acid salts such as ammonium sulfate are added to increase the rate of cure of the urea-formaldehyde resin when under pressure and subsequently heated in hot presses. Some acid salts cure the urea-formaldehyde sufficiently well under ambient "cold" press conditions. It is evident this type of plywood would be oriented toward interior use such as furniture. If water-proof type bonds are required of hardwood plywood, then melamine-formaldehyde resins are used in similar mix form but with higher resin solids... 

Organic Extenders. Organic extenders are primarily of two types (1) fillers derived from organic materials and (2) low-cost, naturally occurring or synthetic resins. Of the first type, wood flour, shell flour, and other cellulosic fillers are the most common. They also provide a margin of mechanical property reinforcement because of their relatively high aspect ratio. Of the resinous types these are petroleum-based derivatives as well as soluble lignin and scrap synthetic resins. 

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. 

Coconut shell is the source of two other products, coconut shell flour and activated charcoal. Powdered coconut shell is used in the plastics industry as a compound filler for synthetic resin glues. It is also used as a filler and extender of phenolic molding powders that give a smooth and lustrous finish to molded articles, thereby improving their resistance to moisture and heat. Activated charcoal is an adsorbent for toxic agents. It has been used in gas masks, but can also be used to remove odors and industrial stench. As well, this by-product is a contact catalyst used to facilitate some industrial chemical reactions (61). 

Industrial Flour WF-5, WF-7 - nut shell flour American Wood Fibers, Jessup, MD, USA... 

GlufiL [Agrashell] Walnut shell flour extender/filler. 

PF-resin A, medium alkali content (8-10%) PF-resin B, low alkali content (3-5%) PF-resin C, medium alkali content (6-8%) PF-powder resin, no addition of water, no dissolving of the powder before blending the strands Extender e.g., coconut shell flour. 

Examples of only a few additives are carbon black, carnauba wax, coconut shell, coke dust, macerated filler, shell flour, vermiculite, and wax. Many additives, especially those that are conductive may affect electrical properties. Most plastics, which are poor conductors of current, build up a charge of static electricity. Antistatic agents can be used to attract moisture, reducing the likelihood of a spark or discharge. 

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

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

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