Calcined clay filler

Organofunctional silanes are used to promote polymer-to-filler bonding with clay or siHca fillers. Vinyl silanes are used in peroxide-cured wire insulation to promote stronger bonding with calcined clay fillers. Mercapto silanes are used to treat kaolin clay in sulfur-cured compounds. 

Nylok . [J.M. Huber] Amino-functional calcined clay filler, reinf( cement for polyamide resin systems. 

Clays - Most commercial clays are classified as hydrous. They are undesirable for use in liquid polysulfide base compounds because of their low pH. However, calcined clays have been found to be satisfactory for use in polysulfide compounds because they are less acidic. The best use of calcined clay fillers is in conjunction with precipitated calcium carbonate fillers to produce a compound with a relatively neutral pH value. For example, calcined clay of the type similar to Icecap K has given good results. 

Formulating for low SIC and PF commonly involves choice of ester plasticizers having substantial aliphatic hydrocarbon side chains, use of hydrocarbon secondary plasticizers, use of calcined clay filler, reduction generally of polar additives, and (unfortunately) use of lead-based stabilizers. 

Fig. 2. (a) Brightness improvement obtained by the use of kaolin as a filler in paper and (b), opacity improvement obtained as pulp fibers are replaced with various kaolins. In both cases, A represents fine-particle calcined clay B, high brightness No. 1 kaolin C, coarse-particle water-washed kaolin and D,... 

Mineral fillers are used for light-colored compounds. Talc has a small particle size and is a semireinforcing filler. It reduces air permeabihty and has htde effect on cure systems. Calcined clay is used for halobutyl stoppers in pharmaceutical appHcations. Nonreinforcing fillers, such as calcium carbonate and titanium dioxide, have large particle sizes and are added to reduce cost and viscosity. Hydrated siUcas give dry, stiff compounds, and their acidity reduces cure rate hence, their content should be minimized. 

Carbon blacks are usually used as fillers. The semi-reinforcing types, such as PEP (Past Extmsion Pumace) and SRE (Semi-Reinforcing Pumace) give the best performance (see Carbon, carbonblack). To lower the cost and improve the processibiUty of light compounds, or to lower the cost of black compounds, calcined clay or fine-particle calcium carbonate are used. 

While organo-silane treatments are extensively used in both thermoset and elastomer applications, their use in thermoplastics has so far been somewhat restricted. This is because they do not react with the surface of calcium carbonate, one of the principal fillers used in this type of polymer and because of the lack of a suitable reactive functionality for most of the thermoplastic polymers. Today they are principally used in conjunction with glass fibres, calcined clays, aluminium and magnesium hydroxides, micas and wollastonite. The main thermo-... 

Clay minerals are widely used in the filler industry and the production of the various types has been described by Hancock and Rothon [85]. The products available range from unaltered kaolin to products produced by calcination. Kaolin deposits are widespread throughout the world. While simple clay minerals are extensively used as fillers in elastomers, their use in thermoplastics is more restricted and the principal products used are those obtained by calcination of ka-olinite. Thus metakaolinite finds application in PVC and silane treated calcined clay in polyamides. The production of these forms only is discussed below. 

Fillers. Fillers are used to improve strength and stiffness, to lower cost, and to control gloss. The most common filler is calcium carbonate, which ranges in size from 0.07 to well over 50 m. Some forms are treated with a stearic acid coating. Clay fillers, such as calcined clay, improve electrical properties. Glass fibers, talc, and mica improve tensile strength and stiffness, but at a loss in ductility. 

Figure 8.62 shows the compression set of rubber with different fillers at 1 1 proportion to rubber.Fillers, such as precipitated calcium carbonate, whiting, calcinated clay, each of which have limited interaction with the matrix give a substantially lower compression set. As the interaction between filler and the matrix... 

Typical fillers calcium carbonate, calcinated clay, aluminum hydroxide, magnesium carbonate, magnesium hydroxide, antimony trioxide, calcium borate, huntite, hydromagnesite, zinc oxide, talc, silica... 

Typical fillers carbon black, calcium carbonate, dolomite, clays, calcinated clays, talc, soapstone, zinc oxide, filmed silica, borates, iron oxide, zinc oxide, magnesium carbonate, pulverized polyurethane foam, barium and strontium ferrites, magnesium aluminum silicate, nylon fibers, quartz in EMI shielding field silver plated aluminum, silver plated nickel, silver coated glass spheres, silver plated copper, silver, nickel and carbon black... 

As mentioned earlier (section 19.2), the addition of filler reduces the transmission ofinlrared energy through a greenhouse film. Figure 19.21 shows the effect of various fillers in energy conservation applications. Calcinated clay gives the best... 

This is essentially hydrated aluminium silicates derived from natural deposits. There are soft clays, hard clays, calcined clays and treated clays. This is a common filler in the manufacture of acid resistant ebonites, natural soft rubbers and in Neoprene compounding for phosphoric acid duties. 

The use of calcined clay as a filler has shown to lead to the release of soluble aluminium from rubber closures into the parenteral solution (Milano et al., 1982). Various techniques for the determination of soluble aluminium in rubber closures have been proposed (Mondimore and Moore, 1983). There has been concern about aluminium since the 1970s, when a link was identified between high aluminium levels in tap water used for renal dialysis equipment and accumulation of the element in the brain. The injection of parenteral solutions into the body effectively bypasses the normal defence mechanisms and under these circumstances may present a challenge to the normal metabolic processes (Massey and Taylor, 1989). In response to these challenges, suppliers have developed rubber formulations that are essentially free from materials containing aluminium compounds. 

Calcined clay and precipitated or water ground calcium carbonates of less than 3 ym are the most common fillers used with PVC. Other fillers used are shown in Table XI. 

Fillers increase the strength, impart needed rheological properties, and reduce the cost of sealants. Tensile properties are increased significantly, depending on the type of filler, its particle size, and the type of cure. Improper filler selection can ruin the performance of a polysulfide sealant. Calcium carbonates (wet or dry ground limestone, precipitated), carbon blacks (furnace, thermal), calcined clays, silica and silicate fillers, and rutile titanium dioxide are typical fillers used in polysulfide sealants. Generally, combinations of fillers are used in formulation. Plasticizers improve the working properties while... 

Clay n. Any naturally occurring sediment rich in hydrated silicates of aluminum, predominating in particles of colloidal or near-colloidal size. There are many types of clays and clay-like minerals. Those of particular interest to the plastics industry are varieties refined by nature and man to a state of good color and particle-size distribution, such as kaolin (China clay). They are used as fillers in epoxy and polyester resins, PVC compounds, and urethane foams. Calcined clays are those that have been heated to a high temperature to drive off the chemically bound water, sometimes also surface-treated to improve their chemical inertness and moisture resistance. They are used primarily in vinyl insulation. 

Titanium oxide and calcined clay can be used as filler materials in the preparation of neutral to weakly acidic papers. 

Graft copolymers between unsatnrated acids, especially acrylic acid and maleic anhydride (MA), and polyolefins (PE and PP) are widely used as surface modifiers and compatibilisers, sometimes in combination with bi-functional coupling agents [46], for talc, calcium carbonate and calcined clays. Such polymer coatings include polypropylene-maleic anhydride [47], polypropylene c/s-4-cyclohexene-l,2 dicarboxylic acid [48], polystearyl or polylauryl acrylate [49], polypropylene-acrylic acid, partially oxidised poly(butane diol) [50] and ethylene-vinyl acetate copolymers [51]. Acid-containing products can react with basic fillers. With most other types, they will simply adsorb on to the mineral surface, but they can form esters with some non-basic metal hydroxyls, notably silanols. 

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