MAIN Governing Factors Influencing Mechanical Properties of Short Aramid-Fibres Reinforced Elastomers

Short fibres are embedded into many types of polymers to raise mechanical properties, in particular the E-modulus, and for reasons of cost reduction of moulded articles. In elastomeric applications they are of limited use because of difficulties to achieve uniform dispersion, lack of interaction between fibres and polymers and fibre breakage during mixing and further processing.

 

In order to obtain optimal performance of short-fibres in elastomers, there are several important governing factors which need special attention:

• The interaction/coupling of the fibres to the matrix polymer, in order to withstand shearing forces exerted on the fibre-matrix interface during deformation of the composite;

• Homogeneous dispersion of the fibres, without fibre clusters;

• Orientation of the short fibres in the matrix, to provoke anisotropy in properties, whenever needed.

In the presentation, a new coupling concept for a short aramid-fibre styrene-butadiene rubber composite is presented. In a mechanistic approach, the relationships between various factors: amount of fibres, processing parameters during mixing, fibre orientation and fibre-rubber interaction, on curing behaviour and mechanical properties are elucidated. The relative importance of either factor in achieving optimal performance is quantified.