Influence of polysiloxane microspheres on hydrophobicity, structure and mechanical properties of paper materials

Abstract

The aim of the study was to investigate the impact of three types of polysiloxane microspheres on the barrier properties, structure and mechanical properties of paper. An influence of new silicon filler on properties of cellulose paper sheet was analyzed. Polysiloxane microspheres were used as an additive introduced into the network of cellulosic fibers in order to obtain new functional properties of the paper. The following types of microspheres were used in the research: M1 hydrophilic of average diameter 23.5 µm, M2 hydrophobic of average diameter 3.1 µm and M3 hydrophobic of average diameter 23.5 µm. The obtained handsheets were analyzed for changes in apparent density, roughness, tensile strength, bursting strength, and tear resistance. Wettability and resistance to liquid were characterized by contact angle measurement, penetration dynamics analysis and uniformity of liquid penetration measured using an extended liquid penetration analyser. It was found that the presence of M2 (small diameter) microspheres improved significantly the paper’s hydrophobicity without changing the mechanical properties. The addition of M1 and M3 (large diameter) microspheres decreased the mechanical properties of the paper samples and did not improve their hydrophobicity. However, M1 microspheres resulted in increased uniformity of liquid penetration through the paper structure. The presented studies also show that it is possible to obtain paper with high hydrophobic properties only through the filling application when polysiloxane microspheres are used for this purpose. The results also indicate that it is not necessary to hydrophobize the entire material structure in order to achieve its high hydrophobicity. Graphic abstract