Adhesives starch sulfates

Fillers (calcium carbonate, calcium sulfate, aluminum oxide, bentonites, wood flour) increase the solid content of the dispersion, and they are added up to 50%, based on PVAc. The purpose of their addition is the reduction of the penetration depth, a thixotropic behavior of the adhesive, gap filling properties, and the reduction of the adhesive costs. Disadvantages can be the increase of the white point and possibly the more marked tool wear rate due to greater hardness of the adhesive. Other components in PVAc formulations are defoamers, stabilizers, filler dispersants, preservatives, thickeners (hydro-xyethylcellulose, carboxymethylcellulose), poly(vinyl alcohols), starch, wetting agents, tackifiers, solvents (alcohols, ketones, esters), flame retardants, and others. 

Alkenyl succinic anhydride Ammonium laureth sulfate Ammonium lauryl sulfate Beeswax C18-28 alkyl acetate Chitin Coco/oleamidopropyl betaine Decylamine oxide Diethylaminoethyl stearate Glycol stearate SE Maltodextrin Myristamidopropyl dimethylamine PEG-5 lauramide Rapeseedamidopropyl benzyidimonium chloride Rapeseedamidopropyl ethyidimonium ethosulfate Rapeseed amine Sodium lauryl sulfate Sucrose cocoate Tallowamide DEA viscosity builder, adhesives Corn (Zea mays) starch Methyl rosinate PEG-2 laurate SE Silica, fumed Xanthan gum viscosity builder, agric. 

Although TLC plates may be prepared in the laboratory, their ready commercial availability generally makes this unnecessary. The plates are produced by mixing the adsorbent with a small quantity of a binder such as starch or calcium sulfate and spreading the mixture as a layer approximately 250 p, thick on the supporting plate. The binder is needed for proper adhesion of the thin layer of adsorbent to the plate. TLC plates should be dried in an oven for an hour or more at 110 °C prior to use, to remove any atmospheric moisture adsorbed on them. This is necessary because the activity of the adsorbent and its effectiveness in separating the components of a mixture are decreased because water occupies binding sites on the surface of the solid. 

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