Surface modification of iron oxide (Fe₂O₃) pigment particles with amino-functional polysiloxane for improved dispersion stability and hydrophobicity

Abstract

Purpose – The purpose of the present study is to use an amino-functional polysiloxane for the surface modification of red iron oxide (Fe2O3) pigment particles for their improved dispersion stability and hydrophobicity and to study the chemical interactions of polysiloxanes with the particle surface. Design/methodology/approach – Surface-treated red Fe2O3 pigment particles were prepared by treatment of the particles with different quantities of the (aminopropylmethylsiloxane)-dimethylsiloxane copolymer in concentrated suspensions in water. The samples were analysed with different instrumental and spectroscopic techniques to study the interaction of the polysiloxane with the particle surface and the effect of the surface treatment of the particles on their dispersion stability and hydrophobicity. Findings – Chemisorption of the amino-polysiloxane onto the surface of Fe2O3 particles resulted in stable layers which turned out to be helpful in improving greatly the dispersion stability of the particles as shown by the Static Light Scattering and Dynamic Light Scattering results. Formation of a polysiloxane coating onto the surface of the pigment particles was confirmed by studying the interactions of the polymer molecules with Fe2O3 surfaces by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy techniques. Practical implications – The surface-treated red Fe2O3 particles with improved dispersion stability can be important components of various formulations in applications such as the colouring of the cement or inorganic pigment-based paint formulations. Originality/value – The study provides mechanistic insights about the interactions of amino-polysiloxane with the red Fe2O3 particles. The process of surface modification of red Fe2O3 particles with the amino-functional polysiloxane showed increased hydrophobicity and dispersion stability which is an important requirement of the pigment-based formulations in real applications.

Applications of magnetic materials separation in biological nanomedicine

“…In order to preserve their specific magnetic properties, and to protect these NPs from both oxidation and agglomeration, the application of the encapsulation procedure has been proposed . A MNP can be copolymerized and modified to give a variety of reactive functional groups(such as ‐OH,‐COOH,‐CHO,‐NH 2 ) on their surface, and then coupled with many biological macromolecules such as cells, enzymes, proteins, antibodies and nucleic acids, so that it can be specifically targeted to separate substances .…”

Polymerizable Ligands as Stabilizers for Nanoparticles

“…Active targeting and imaging of prostate cancer [53] Polyethylene glycol (PEG) Decreased nanoparticle cytotoxicity by PEG coating of iron oxide nanoparticles [54] Poly(acrylic acid) PAA Removal of pollutant dyes from water. Pollutant remediation systems [55] polystyrene or polyisoprene Lithographically patterned micro-structured sample holders [56] Amino-functional polysiloxane Improvement of dispersion stability and hydrophobicity of the particles [57] www.particle-journal.com www.MaterialsViews.com…”

Preparation of amino functional polysiloxane–lanthanide (Dy3+ and Sm3+) composites

“…14 –16 The presence of amino groups in the amino polysiloxanes imparts new properties such as reactivity, surface activity, and adsorption properties. 17 –19 The polysiloxane–lanthanide complex can be prepared by introducing the fluorescent groups into the polysiloxane chain using the reactivity of the amino group. Polymer–lanthanide complexes not only have the unique optical properties of lanthanide ions but also have good mechanical properties such as easy processing formability, impact resistance, and lightweight.…”