Glass fibre filler

Applications of scanning electron microscopy (SEM) to polymer characterisation and microstructure include studies on the zwitterions-type polymer, poly(3-diethyl methylmethacryloyl ethyl) ammonium persulfonate grafted on to a silica surface by treatment of poly(2-dimethyl amino) ethyl methacrylate [2], polyaniline coated glass fibre fillers with different polyaniline contents [3], and also studies on ultra high molecular weight blends [4] and high-density polyethylene (HDPE)-gamma ferric oxide composite films [5]. 

Nylon exhibits low friction properties giving excellent resistance to abrasion and wear with good temperature resistance and dimensional stability especially when formulated with mineral or glass fibre fillers. Bearings and moving parts are among nylon s applications. 

Some polymeric samples can be examined directly without prior treatment. For example, thin polymeric films may be used for infrared transmission spectra and samples with glass-fibre fillers may be examined by Raman directly. 

This is also known as Bulk Moulding Compound (BMC). It is blended through a mix of unsaturated polyester resin, crosslinking monomer, catalyst, mineral fillers and short-length fibrous reinforcement materials such as chopped glass fibre, usually in lengths of 6-25 mm. They are all mixed in different proportions to obtain the required electromechanical properties. The mix is processed and cured for a specific time, under a prescribed pressure and temperature, to obtain the DMC. 

Incorporation of fillers such as glass fibre, wood flour, etc. 

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. 

Several blends based on polysulphone materials have been marketed. Probably the most well known is Mindel, originally produced by Uniroyal, acquired by Union Carbide, but now marketed by Amoco. Whilst not exhibiting the heat resistance of the unblended homopolymer, Mindel materials, which are blends of polysulphone and ABS, are lower in cost, easier to process and have higher notched impact strengths. The Mindel A materials are unreinforced, the Mindel B grades contain glass fibre, and the Mindel M grades contain other mineral fillers. A related polysulphone/SAN blend has been marked as Ucardel. 

Industrial grade materials employ fillers such as asbestos, silica and glass fibre. These are incorporated by dry-blending methods similar to those used with woodflour-filled phenolic compositions. 

Miscellaneous uses include textile bobbins, guns for hot melt adhesives and bilge pump housings. These materials are normally found in reinforced form. In addition to glass fibres, other fillers such as glass beads, talc and mica are used in conjunction with coupling agents. 

Such is the anisotropy that flexural modulus may be four times as high in the flow direction as in the transverse directions. This difference may be reduced by incorporating fillers such as glass fibre or mica. 

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. 

With the exception of epoxy resins, when a resin is fully polymerized it loses any irritant properties. However, associated materials, e.g. glass fibre used as a filler, or the dust from plywood or veneers, may promote initation. Partially-cured resins will retain some uritant properties. Traces of cutaneous or respiratory sensitizers liberated, e.g. by heating or machinery, may be problematic. 

Coupling Agents. Coupling agents are added to improve the bonding of the plastic to inorganic filler materials, such as glass fibres. A variety of silanes and titanates are used for this purpose. 

A pyrolysis technique was investigated as a method for the chemical recycling of glass fibre-reinforced unsaturated polyester SMC composites. The proeess yielded liquid products and gases and also a solid residue formed in the pyrolysis of glass fibres and fillers. The solid residue was used as a reinforeement/filler in unsaturated polyester BMC composites, and the influenee on mechanical properties was studied in comparison with BMC prepared entirely from virgin materials. 

Alternative proeesses for the reeyeling of fibre-reinforeed plastie (FRP), and their applieation in Japan, are briefly reviewed. Pulverised waste has been used in plastie mouldings for automotive applieations, and in eement roof tiles. FRP may be burned in ineinerators and used to heat water, or as an additive to eement kilns, where the resin aets as a fuel and the glass and filler beeome eement raw materials. Pyrolysis, in eonjunetion with metal eatalysts, has been used to reduee the waste to oils or gases, and treatment with steam or supereritieal water has also been sueeessfully applied. 26 refs. 

Filler/reinforcementi c Active fillerc Carbonates, glass fibres, Al(OH)3, kaolin, talc, silica, wollastonite, glass spheres, mica Al, Ca, Fe, Mg, K, Na, S, Si, Zr... 

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