Filler reinforced

Corray 40 carbon black cyclop araffinic hydrocarbon processing aid softens, swells, and smooths reclaim reinforcing filler... 

Carbon Black. This is the principal reinforcing filler used in mbber. Carbon black is made by three processes the furnace process, the thermal process, and the channel process. Over 97% of black is made by the furnace process (see Carbon, carbon black). 

Silica. The main uses of siUca are in the treads of off-the-road tines for improved chunking and tear resistance and as a component of the bonding system for brass and 2inc-plated steel cord. These are commonly used in radial passenger and tmck tire belt skim stock. In addition the body pHes of steel radial tmck tires, hoses and belts, and footwear use significant volumes of siUca as a reinforcing filler. 

Reinforcing Fillers. Carbon black is by far the most heavily used reinforcing filler for tire compounds. Annual tire usage of all grades of carbon black is estimated to be over three million metric tons aimuaHy. 

Clays. Clay, which is generally considered a mild reinforcing filler, is used sparingly in tires. It is most often used in white sidewalls or in low performance tires. Clay toimage in tires worldwide is estimated at 36,000 t annually. Clay can also be coupled to mbber with silanes, and this is the more popular version used in tires. Even with silane coupling, clays are still a weak reinforcing filler compared to both carbon black and siUca. 

Fumed sihca, a highly reinforcing filler, is usually added in amounts ranging from 6 to 20%. Sihca is most often used when a high strength sealant is desired. Several sihcas having different surface areas are available and surface treatment with silanes may be used as well. 

Large amounts of iaert fillers, such as whiting, talc, and clays, can be added. Very dense fillers, such as barium or strontium sulfates, are used to make compounds intended for sound-deadening appHcations. In contrast, high levels of reinforcing fillers, such as carbon black, produce undesirable properties ia the final product. 

The higher molecular-weight soHd epoxy resins are used in formulations that usually consist of a resin, hardener, reinforcing filler, pigments, flow control agents, and other modifiers. In addition to using conventional hardeners in these formulations, epoxy resins can also be hardened with other resins, ie, acryhcs or polyesters. 

Particulate fillers are divided into two types, inert fillers and reinforcing fillers. The term inert filler is something of a misnomer as many properties may be affected by incorporation of such a filler. For example, in a plasticised PVC compound the addition of an inert filler will reduce die swell on extrusion, increase modulus and hardness, may provide a white base for colouring, improve electrical insulation properties and reduce tackiness. Inert fillers will also usually substantially reduce the cost of the compound. Amongst the fillers used are calcium carbonates, china clay, talc, and barium sulphate. For normal uses such fillers should be quite insoluble in any liquids with which the polymer compound is liable to come into contact. 

For equivalent particle size the carbon blacks are the most powerful reinforcing fillers. However, fine particle size silicas can be very useful in non-black compounds whilst other fillers such as aluminium hydroxide, zinc oxide and calcium silicate have some reinforcing effect. 

Commercial grades of polymer may contain, in addition to glass fibre, fire retardants, impact modifiers and particulate reinforcing fillers. Carbon fibre may be used as an alternative to glass fibre. 

The reinforced reaction injection moulding (RRIM) process is a development of RIM in which reinforcing fillers such as glass fibres are incorporated into the polymer. One advantage of such a system is to reduce the coefficient of thermal expansion, and with a 40-50% glass fibre content the coefficient is brought into line with those of metals. 

Room temperature vulcanising silicone rubbers (r. t. v. rubbers) have proved of considerable value where elaborate processing equipment is not available. These rubbers are low molecular weight silicones with reactive end-groups and loaded with reinforcing fillers. The RTV silicone rubbers may be classified into two types ... 

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