Processing aids, definition

Single-screw extmsion of rigid PVC definitely requires the use of a process aid to achieve optimum quality and production rates. Typically, 1.5-3.0 phr is sufficient. While not absolutely necessary in low-shear, twin-screw extmsion, the inclusion of at least 1.0-1.5 phr of a process aid definitely enhances product quality. Because of its effect on promoting powder fusion, a slightly lower barrel temperature profile may be used when running with a compound containing process aid on a twin-screw extrader. 

Definition Limit of quantitation is a parameter of quantitative assays for low levels of compounds in sample matrices, such as impurities and degradation products in food additives and processing aids. It is the lowest concentration of analyte in a sample that can be determined with acceptable precision and accuracy under the stated experimental conditions. The limit of quantitation is expressed as the concentration of analyte (e.g., percentage, milligram per kilogram, parts per billion) in the sample. 

Definition Reaction prod, of microciystalline wax and oi en Uses External lubricant, processing aid, slip agent, antiblocking agent, scuff/mar resist, aid in plastics, styrenics, polyolefins, TPOs, for formulation of emulsions, coatings, textile finish softeners, floor, auto, and liq. solv.-based polishes modifier in solvent polish systems car-nauba substitute... 

Definition Extract derived from Aiiium sativum Properties Pungent acrid aromatic garlic odor Uses Natural flavoring agent and adjuvant in foods food processing aid (Japan)... 

Definition End prod, of controlled hydrogenation of soybean monoglycerides Properties Nonionic Uses Emulsifier, emollient, stabilizer, dispersant, opacifier for cosmetics, foods, pharmaceuticals lubricating greases synthetic waxes textile lubricants antistat, lubricant, processing aid in plastics, nonwoven fibers dispersant for color cones. defoamer in food-contact paper/paperboard in food-contact textiles... 

Definition Methyl ester of cottonseed oil Uses Solvent, cosolvent, penetrant in industrial, food processing, and agric. applies. in textile processing aids in printing inks Trade Name Synonyms Norfox MCS [Norman, Fox http //www.norfoxx.com]... 

Synonyms 1,3-Bis (2-hydroxypropoxy) benzene Definition Hydroxypropyl ether of resorcinol Toxicology Eye irritant Uses Chemical intermediate processing aid and chain extender for PU elastomers Trade Name Synonyms HPR [Indspec... 

These two examples illustrate that different food additive definitions tend to be very similar because a general consensus has been reached among the majority of countries as to what an additive is. It should also be pointed out that a special statute is normally reserved for dietetic products, nutritive substances added to food products (e.g., vitamins, amino acids, minerals, etc.), technological processing aids, and aromas. 

The sol-gel blend or pre-crosslinked grades of polychloroprene such as the T Type polychloroprenes available from DuPont Dow contain a highly cross-linked network, which that acts as an internal processing aid (94,95). The hlend has many of the same characteristics as the sol component, hut different compoimd rheology properties. This composition results in faster extrusion with extrudates having smoother surfaces. Extrudates also retain their shape better with good definition until vulcanized. 

The ISO definition of a process aid is a compounding material which improves the processability of a rubber compound. The ideal para-... 

It takes the chemical yield into account and includes all reagents, solvent losses, all process aids, excluding water however because it would lead to exceptionally high E-factor figures, which eventually make the comparisons of processes difficult. The definition of total waste is not entirely clear, and boundaries must be drawn to decide whether factors such as emissions, energy use and solvent are accounted for. ... 

Definition Mixture of syn. fatty alcohols with 20-40 carbons in the alkyl chain Uses Antioxidant heat stabilizer UV stabilizer vise, depressant emulsifier in cosmetics emollient protective f Im-former for skin care prods, food-pkg. adhesives chemical intermediate for oxidation, ethoxylation, sulfation, amination, esterification coemulsifier and direct additive in coatings processing aid, lubricant, dispersant in plastics... 

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