Paint constituents extenders

Extender an inorganic material in powder form which has a low refractive index and consequently little obliterating power, but is used as a constituent of paints to adjust the properties of the paint, notably its working and film-forming properties and to avoid settlement on storage. 

Chemical Composition. The extenders should be chemically inert in the paint. Secondary constituents (e.g., iron ions) may produce color changes. Sulfates, sulfides, alkali, alkaline-earth, and heavy-metal ions may cause problems due to their chemical reactivity and toxicity, and also affect abrasion and weather resistance. 

Definition Clay (an aluminum silicate) mineral main constituent of kaolin Formuia AI2O3 2Si02 2H2O Uses Extender pigment offering hiding power and suspension, flow control used in interior emulsions and primer paints and polyester premix plastics coagulant aid for water treatment... 

Ext. D C. Colorants not certifiable for use in oral products but considered safe for use in externally applied products specifically excludes colorants that may have oral toxicity, extender. A low-gravity material used in paint, ink, plastic, and rubber products to reduce cost per volume by increasing bulk. Some example of extenders are diatomaceous earth, wood floe, mineral rubber, etc. In the food industry, soybean is used as an extender in meat products, providing equivalent nutritional value at a lower cost, extract. A product derived from vegetable matter by the application of solvents, heat or pressure to separate it from the other constituent parts, extraction. The process of treating a natural raw material with an organic solvent. The solvent portion containing the extracted material is filtered and the solvent removed. The extract will contain nonvolatile as well as volatile components. Oleoresins, resinoids, concretes, and absolutes are all produced by extraction. 

All paint systems may be considered as a combination of a small number of constituents. These are eontinuous phase or vehicle (polymer and diluent), discontinuous phase or pigment and extender, and additives. 

It is clear that, since the pitMieering work of Hermann Staudinger, the science and technology of polymer chemistiy has grown immensely, enriched by the work of innumerable research and engineering laboratories, and it will continue to do so. The present contributiOTi tries to paint one aspect of the full picture and to point to some fines of development. The incorporation of constitutional dynamics opens new perspectives. The analysis above may be extended to any set and network of dynamers, with more constituents, for which application of a given action will lead to a complex constitutional variation, resulting in a novel set of... 

Generally coating compositions consist of quite a few different raw materials. Emulsion polymers as binder as well as pigments and extenders are the most crucial and basic constituents. They usually make up for the major part of a coating. However, they cannot be formulated into a paint that fulfils the required application properties. Additives have to be employed to adjust flow behaviour, ensure a proper dispersing of the pigments, improve film formation, control foam formation, prevent microbiological attack etc. (Bielemann, 2000). 

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