Fillers barytes

Fillers (qv) are occasionally used in flexible slab foams the two most commonly used are calcium carbonate (whiting) and barium sulfate (barytes). Their use level may range up to 150 parts per 100 parts of polyol. Various other ingredients may also be used to modify a flexible foam formulation. Cross-linkers, chain extenders, ignition modifiers, auxiHary blowing agents, etc, are all used to some extent depending on the final product characteristics desired. 

For electrical insulation china clay is commonly employed whilst various calcium carbonates (whiting, ground limestone, precipitated calcium carbonate, and coated calcium carbonate) are used for general purpose work. Also occasionally employed are talc, light magnesium carbonate, barytes (barium sulphate) and the silicas and silicates. For flooring applications asbestos has been an important filler. The effect of fillers on some properties of plasticised PVC are shown in Figure 12.21 (a-d). 

Barthlott, Wilhelm, 22 108 Bartles-Mozley concentrator, 16 631 Baryte, as filler, 11 311 Basan, molecular formula and structure, 5 94t... 

The principal characteristics of polymers which control their ability to dissipate energy are their stiffness, surface mass, and their inherent damping characteristics. In this chapter we are only concerned with the last of these three. Briefly, however, if lack of stiffness is a problem with a particular polymer in a damping system, this can be enhanced, if not completely obviated, by using the material in a constrained layer (29) mode. Surface mass refers to the mass of material behind a unit surface area. Clearly, for polymers which are all inherently low density materials, this can be increased by the incorporation of dense, particulate fillers such as lead, barytes etc. 

Resin Mortars The following organic/polymeric mortars are used in CRM construction, all being usable in HF exposures if non-silica fillers such as carbon or barytes are employed ... 

Furan Mortars Furans have the broadest range of resistance to both acid and alkali (pH 0-14) and temperatures of all the resin mortars. Furan mortars can accept temperatures up to 350°-360°F. Modified furans are available that can withstand continuous temperatures of up to 425°F and intermittent temperatures to 475°F. Unlike the other mortar materials, furans have excellent resistance to strong alkalies as well as non-oxidizing acids and many organic chemicals. However, furan mortars are attacked by some organic solvents such as aniline. Furans are available with silica, carbon or barytes fillers, the filler choice depending upon the environmental conditions. 

Inexpensive, finely ground minerals like barium sulfate (barytes), dolomite, limestone (whiting), clays, and silica are widely used to provide bulk and reduce the cost of friction material formulations. These materials also act as friction modifiers and alter the performance of the end product. Other less commonly used fillers are hollow and solid organic and inorganic microspheres and fly ash. 

Diluting fillers such as clays, talc, and barytes act as diluents to cut costs. 

The use of inert materials in vinyls is widely practiced. The filler can be used to lower cost and increase hardness. The most common types of fillers in use today include the calcium carbonates and silicate types. Also available are various silica gels, barytes, gypsum, alums, wood flour, and antimony oxide. Depending upon the oil absorption value of the inert material, a filler will (1) lower tensile properties, (2) increase hardness, (3) lower flexibility, and (A) increase processing temperatures. 

Fillers, usually barium sulfate (barytes) or calcium carbonate (whiting)... 

Minex 10 No. 22 Barytes " Raven 850 Ultra-Pflex filler, polyester gelcoats Minex 10... 

Inorganic materials such as chalk, flour, china, clay, mica, barytes. Fuller s earth, Aerosil (finely divided Si02), asbestos, glass-fiber, and metal or oxide single crystals (whiskers) are all used as fillers. Organic fillers include wood flour, cellulose flakes, foam-rubber chips, paper cuttings. 

The most common fillers used are barytes, especially because of their off-white to cream and even dark brown colour, which renders them particularly suitable for wood. They are used generally in the proportion of 35 to 40% of the total adhesive system but can be used even up to 50%. The primary aim of the filler is to reduce costs, but it has also a positive effect on the cohesive strength of the adhesive, and gives to the molten adhesive some body . 

Celestite n. Mineral, which is chiefly strontium sulfate. When ground, it has some application as a filler, being used as an alternative to barytes. The ground mineral is also known as strontium white. 

Sales of barytes as a filler in Europe in 2003 have been reported by the Barytes Association as 282,000 tonnes, but this includes coatings and rubbers as well as plastics. Barytes is used in plastics to improve friction and wear and sound insulation, and in polyurethane foams to improve resilience. 

Barite (baryte, heavyspar) Oil-well drilling muds, filler in rubbers, paint extender, aggregate in speciality heavy weight concretes, flux in the glass industry, and barium chemicals... 

Development and use of additives to improve sound insulation properties of plastics compounds (especially required by the automotive industry) has been a strong theme of recent development. In the past, insulation theory has taken it that the most significant factor is mass, and by increasing it, insulation can be improved. This has led to use of heavy loadings of heavy fillers, such as barytes, but it goes diametrically against the other requirement of the automotive industry, reduction in weight. 

Baryte is predominately barium sulfate (BaS04) that is available in particle sizes from 1 to 20 /u.m. It is used as a filler when a high specific gravity is required of the polymer article. Typical polymer loading levels are 25-100 phr for articles such as stoppers and seals. 

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