Abrasion resistance injection moulding

Laboratory tests and experience during use have demonstrated that the nylons have extremely good abrasion resistance. This may be further improved by addition of external lubricants and by processing under conditions which develop a highly crystalline hard surface e.g. by use of hot injection moulds and by annealing in a non-oxidising fluid at an elevated temperature (150-200°C for nylon 66). 

The drive sprocket is injection-moulded in rubber-toughened PA6.6, which is resistant to repeated impact over a wide range of temperatures, and which shows excellent abrasion resistance. The plastic sprocket absorbs the shock of gear changes better than metal, causes less wear on the chain, and provides a quieter ride. The polymer is resistant to lubricants and other liquids. Reduced firiction improves power transmission and, coupled with a lower weight, results in better performance. 

In 1996,20 million lbs of rPET was used in applications in which it was first combined with another resin. This process, known as alloying or compounding, greatly increases the chemical resistance, dimensional stability and abrasion resistance. PET, both rPET and vPET, cannot easily be injection moulded PET will randomly crystallise during normal thick wall moulding thus making the moulded part brittle and subject to warp. The process of adding an impact modifier to PET allows it to overcome these problems and enables it to be used in other applications. 

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