Investigation of the setting of polyamide fibre/latex-filled plaster composites

We have investigated the setting of binary blends (latex-filled plaster and polyamide fibre-reinforced plaster materials) and ternary blends (polyamide fibre-reinforced latex-filled plaster materials). The influences of the latex (nature and concentration) and the fibres (concentration, length and diameter) were analysed in terms of the setting time, the total swelling and the hydration of the plaster. The association of hydrophilic polyamide fibres with plaster disturbs the hydration, and the setting time of the plaster/latex binary blends depends strongly on the nature of the polymer. The choice of the proper latex to be associated with the plaster was made looking upon its influences on the setting time and the mechanical properties of the blend. The ternary blends were characterised by a drastic increase of the setting time correlated with a reduction of the total swelling.