High molecular weight organic compounds

Plastics are high-molecular-weight organic compounds of natural or mostly artificial origin. In fabrication, plastics are added with fillers, plasticizers, dyestuffs and other additives, wliich are necessary to lower the price of the material, and give it the desired properties of strength, elasticity, color, point of softening, thermal conductivity, etc. 

The term plastic comes from the Greek word to form. It identifies many different plastic materials. Polymers, the basic ingredients used in practically all plastics, can be defined as high molecular weight organic compounds, synthetic or natural substance... 

About half of the dissolved organic carbon may appear in humic or fulvic acids. These are high-molecular weight organic compounds of a composition which is somewhat uncertain. They contain aromatic hydroxyl and carboxyl groups which have the ability to bind to metal ions. Rivers and estuaries typically contain 10 mg/liter of acid with an exchange capacity of 5-10 mmol/g, mainly due to carboxylic... 

An allergen is a chemical or substance that results in an immimoglobulin E-mediated (antibody) allergic response. Allergens are usually high molecular weight organic compounds. The production of antibodies... 

Humic substances High-molecular-weight organic compounds that are variable in composiUon, have complex structures, and are relaUvely inert. They comprise a large fracUon of the DOM. Found in sods, sediment, fresh, and seawater. 

Comparison of High Molecular Weight Organic Compounds Isolated from Drinking Water in Five Cities... 

CHIAN et al. High Molecular Weight Organic Compounds 195... 

A high molecular weight organic compound, natural or synthetic, whose structure can be represented by a repeated small unit, the monomer (e.g., polyethylene, isoprene and cellulose). Synthetic polymers are formed by the addition or condensation polymerization of monomers. If two or more different monomers are involved, a copolymer is obtained. Some polymers can be rubbers and some can be plastics. Plastics which are also high polymers can include both natural, or synthetic products but exclude rubber whether natural or synthetic. At some stage in its manufacture every plastic is capable of flowing under heat and pressure into the desired final shape. 

Plastic (adj.) is defined by Webster as capable of being molded or modeled (e.g., clay)... capable of being deformed continuously and permanently in any direction without rupture. Plastic (n. ) in modern industry covers high-molecular-weight organic compounds that can be formed into any desired shape and then solidified into a useful product that can withstand the mechanical stresses normally applied to it. 

The haze which can be seen in fair weather is mainly due to submicron ammonium sulphate particles. This aerosol also contains soot, agglomerates of very small carbon particles with adsorbed high molecular weight organic compounds and appreciable amounts of certain trace elements, e.g. lead, zinc, iron, nickel, cadmium etc. 

Ultrafiltration membranes are suitable for the treatment of radioactive liquid wastes, especially as reverse osmosis pretreatment [6]. Therefore, ultrafiltration is used for the removal of the radioactivity associated with the proteins and high-molecular-weight organic compounds, as these species can reduce reverse osmosis performance. 

Ultrafiltration. In this stage, high-molecular-weight organic compounds as well as biological contaminants are removed, and the activity is reduced to an average of 50%-60%. 

P. J. Flory, Condensation Polymerization and Constitution of Condensation Polymers, in R. E. Burk and O. Grummitt, Eds., High Molecular Weight Organic Compounds, Frontiers in Chemistry, Vol. VI, Interscience, New York, 1949, pp. 211—283. 

Diesel exhaust particles (DEP) are composed of carbon black and adhered lipophilic and hydrophilic compounds that include approximately 18,000 different high molecular weight organic compounds, composed of aliphatic and aromatic hydrocarbons, polycyclic aromatic hydrocarbons, polycyclic... 

Burk, R. E., and Grummitt, O., ed.. Frontiers in Chem., 6, 1949. High Molecular Weight Organic Compounds. 

Natural high-molecular-weight organic compounds. These include humic substances and natural organic matter, asphaltene, and cellulose. 

Calcium and phosphate concentrations were measured as a function of pH in [20]. The pH was adjusted by the addition of KOH, KF, ("atNO jj, or K2HPO4. Dissolution is inhibited in the presence of high-molecular-weight organic compounds [146]. 

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