Paper making behaviour of a modified filler obtained by layer-by-layer technique

Abstract

One way of increasing the filler content in paper without sacrificing the mechanical properties is based on the modification of the filler surface with compounds that promote a better bonding with the cellulosic fibres. In this context, sodium alginate was deposited at the surface of precipitated calcium carbonate (PCC) as a first layer and alternated successive layers of Cationic poly(diallyldimethylammonium) chloride – polyDadmac and alginate were applied using a layer-by-layer (LbL) procedure. The analysis of the synthesized new materials showed that there is a deposition of the negative and positive polyelectrolites at the surface of PCC. In fact by XPS it was confirmed that small amounts of the polyelectrolytes are present at the surface of PCC. Papermaking tests were carried out using the new composites. An improvement of the handsheets strength properties was observed when comparing to handsheets produced with the unmodified PCC.