Glass fibre filler polyester resin

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. 

Typical systems are polyester and phenolic resins filled with glass fibres and mineral fillers. 

A mixture of glass fibres, 12-55 mm long, fillers, and catalysed polyester resin sandwiched between 2 polythene sheets to prevent adhesion of the layers and facilitate handling. Two processes are used to make SMC s giving laminates with slightly differing properties ... 

Thermosetting plactics are often reinforced by as much as 100 phr of various fillers, for example, wood flour, cotton flock asbestos and synthetic fibre used with phenolic thermosets, and silica flour, mica or talc with epoxies. Glass fibre reinforcement of polyester resins for structural, automotive, aerospace and marine applications is too well known to require comment. 

Resin transfer moulding (RTM) is a low-pressure variation of transfer moulding where, instead of granules or preforms, a pre-mixed resin and catalyst (hardener) is injected into a closed mould containing dry glass, carbon or aramid fibre reinforcement. When the resin has cooled, the mould is opened and the composite part ejected. The resins used include polyester, vinylester, epoxies, phenolics and methyl methacrylate combined with pigments and fillers. Applications include small complex aircraft and automotive components as well as automotive body parts, baths and containers. 

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