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Two types of amorphous silica namely, the precipitated silica and the pyrogenic silica, were studied. The surfaces of such silica were modified with silane coupling agents such as 3‐aminopropyltriethoxysilane, N‐2‐(aminoethyl)‐3‐aminopropyltrimethoxysilane and 3‐ureidopropyltrimethoxysilane. Pigments were obtained by the adsorption of organic dyes, C.I. Reactive Blue 19 and C.I. Acid Green 16, onto the modified silica surface. Structural properties of the modified silica and the pigments obtained were evaluated using scanning electron microscopy, zeta potential analysis and particle size measurement techniques. Moreover, colour of the pigments obtained was evaluated using the CIE L *a*b* colour space system. The specific surface area of the pigment obtained was estimated using the BET method.

Studies were carried out on the modification of silica with 3‐aminopropyltriethoxysilane in various solvents. The modified silica obtained was subjected to comprehensive evaluations of physicochemical properties, including the bulk density and the capacities to absorb water, dibutyl phthalate and paraffin oil. Particle size, particle size distribution, uniformity of the particles, tendency to form agglomerates, as well as particle surface morphology, were also examined using SEM and dynamic light scattering (DLS) techniques. The properties of the modified silica obtained were compared to evaluate the effects of the solvents used during the surface modification of the silica.

The purpose of this paper is to obtain ZnO‐SiO₂ oxide composites of low bulk density, high homogeneity and consisting of the smallest possible particles. The optimum parameters of precipitation of ZnO‐SiO₂ oxide composites impregnated with natural latex rubber were established. The formation and impregnation the ZnO‐SiO₂ oxide composites were made to occur simultaneously.

The influence of non‐ionic surfactants added during the precipitation process on the physico‐chemical properties of the oxide systems obtained was investigated. The products were characterised by determination of bulk density, absorption capacities of water and paraffin oil, particle size distribution (applying NIBS and laser diffraction methods), as well as SEM observations of surface morphology and microstructure. Moreover, the colorimetric characteristics of the oxide composites obtained and sedimentation profiles in water were analysed. Energo‐dispersive microanalysis of the products enabled determination of the content of ZnO and SiO₂. The surface area (BET) and the size and volume of pores were also estimated.

Modification of the oxide composites with nonylphenylpolyoxyethyleneglycol ethers was found to improve the basic physico‐chemical parameters of the ZnO‐SiO₂ hybrid systems and to change the character of its surface to become more hydrophobic. The conditions in which samples with the best properties were obtained were concluded to be optimum.

Only the selected non‐ionic surfactants were applied as modifying agents of ZnO‐SiO₂.

There is a possible application of ZnO‐SiO₂ oxide composites as activators of rubber compounds and barrier materials in textiles.

The proposed method of ZnO‐SiO₂ oxide composite synthesis in the process of precipitation with simultaneous modification with non‐ionic surfactants provides products with desirable dispersive‐morphological parameters and a hydrophobic surface character.

The study reported here concerned production of green pigments, hydrated nickel(II) silicates and oxides, obtained by precipitation from solutions of sodium metasilicate and sodium hydroxide using nickel(II) sulphate.

The pigments were analysed using a number of techniques including scanning electron microscopy for particle surface morphology and dynamic light scattering for particle structure and the tendency of the particles to agglomerate.

The most desirable physicochemical parameters were shown by highly dispersed nickel(II) silicates precipitated in presence of the modifying agents. Silicate pigments precipitated in the presence of Rokanol K‐7 had low bulk densities, a high capacity to absorb water, dibutyl phthalate and paraffin oil within the primary particles, which is particularly noteworthy.

Due to their good dispersibility, well developed surface and appropriate coating power, coloured silicates of, e.g. chromium(III) and nickel(II) may be used as pigments and fillers for surface coatings.

The method of obtaining nickel(II) pigments developed was novel and provided a solution for problem of post‐galvanic nickel solutions.

Presents the outcome of intensive research into highly dispersed sodium‐aluminium silicate. Optimal conditions of the precipitation process of sodium‐aluminium silicates of high dispersion degrees from the solution of sodium metasilicate were given. In the precipitation process water soluble aluminium salts were used. A physicochemical analysis and microscopic structure of the obtained silicates were performed. The products obtained are characterized by parameters comparable to those of the sodium‐aluminium silicate P‐820 (Degussa).

Proposes to investigate preparation of amorphous silica via precipitation reaction from aqueous solution of sodium metasilicate and hydrochloric acid in emulsion medium, focusing on determination to optimise the dispersive and morphological properties of silicas studied.

The silicas obtained were analysed using modern research techniques, such as scanning electron microscopy for studies on particle surface morphology and dynamic light scattering technique for studies on particle structure and their tendency for agglomeration. Moreover, the sedimentation characteristics of the silica powders were evaluated.

The properties of silicas precipitated from emulsion systems depend on several variables but the amount and concentration of the applied reagents and pH of the emulsion are of critical importance. Using 16, 14 or 12 wt% solution of sodium metasilicate (per SiO₂ content) and 5.0, 4.3 or 3.7 wt% solution of hydrochloric acid, the particles obtained were of best dispersive parameters. Mean diameter, polydispersity, shape and sedimentation of particles reflect the applied preparation procedure. Several of the silicas obtained manifest tendency for formation of secondary agglomerates and aggregates. The pH of the solution obtained from two mixed emulsions exerts a pronounced influence on quality and properties of the prepared silica. The best silica is obtained at pH 6‐7. In the cases where the emulsion has been dosed with “pure” sodium metasilicate solution, particles of irregular shape of high mean particle diameters, with a tendency to form large particle accumulations, have been formed.

In the precipitation reaction, aqueous solution of sodium metasilicate, hydrochloric acid and emulsifiers in the form of non‐ionic surfactants were used as substrates. The organic phase involved cyclohexane. Alternatives could be explored.

The method developed provides a novel and practical solution to precipitation of hydrophilic/hydrophobic silica fillers.

The method for obtaining amorphous types of silica could find numerous applications, particularly as polymer fillers.

Studies on the surface modification of sodium‐aluminium silicate P‐820 using silane coupling agents are described. The best modifiers were selected, which induced a change of the silicate surface from hydrophilic to hydrophobic. Physicochemical analyses of the modified silicate were performed. The methods of evaluating silicate surface modification degree were presented. The degree of hydrophobization of silicate surface was determined by a calorimetric method. Near infra‐red spectroscopy (NIR) was used to determine the degree of condensation of the silicate surface silanol groups. Studies on morphology and microstructure using transmission electron microscopy (TEM) were performed. Attempts were made to apply the unmodified and modified sodium‐aluminium silicate P‐820 as filler and pigment in silicate and dispersion paints.

The purpose of this paper is to report on a method of synthesis of TiO₂‐SiO₂ oxide composites characterised by spherically shaped particles with sizes in the micrometric ranges, which can be applied as a new generation of textile/TiO₂‐SiO₂ composites with barrier properties against UV radiation. Synthesis and characterisation of TiO2‐SiO2 oxide composites with a high degree of dispersion were performed, and their influence on the barrier properties of textile fabrics was investigated.

The precipitation was performed with the use of solutions of titanium sulphate and sodium silicate as the precipitating agent, which are cheap alternatives to organic precursors of Ti and Si. The reaction was conducted in an emulsion system, where cyclohexane was used as the organic phase and non‐ionic surfactants NP3 and NP6 as emulsifiers were applied.

The direction of substrate supply, concentration of the reagents and their ratio and other conditions of precipitation process were found to significantly affect the physicochemical parameters of the pigments obtained. A possibility is provided of manufacturing a new generation of textile/TiO2‐SiO2 composites with barrier properties against UV radiation.

Titanium sulphate, sodium silicate, cyclohexane as the organic phase, and non‐ionic surfactants NP3 and NP6 as emulsifiers, were used.

Synthesis of a new generation of textile/TiO2‐SiO2 composites with barrier properties against UV radiation has been performed. Textile fabrics modified with hybrid composites demonstrated high absorption of UV radiation over the full wavelength range.

Determination of optimum conditions of TiO2‐SiO2 oxide composites precipitation to obtain products with desired physicochemical, dispersive and structural properties. Development of nano‐structural textile composites with barrier properties, protecting against UV radiation.

The purpose of this paper is to characterise the electrokinetic properties of pigments supported on both unmodified and modified silica. The paper describes the preparation of hybrid pigments via adsorption of organic dyes on silica supports and determination of the zeta potential and electrophoretic mobility of the materials obtained.

The materials studied were hybrid pigments obtained as a result of adsorption of two basic dyes: C.I. Basic Red 1 and C.I. Basic Orange 14 and one acidic dye C.I. Mordant Red 3 from solutions of concentrations of 500, 2,000 and 3,000 mg/dm³ on the surface of both unmodified and modified silica supports. The agent used for modification of the silica surface was N‐2‐(aminoethyl)‐3‐aminopropyltrimethoxysilane.

The modification of the silica surface with aminosilane was found to change, significantly, the electrokinetic character of the inorganic support. This change was interpreted as being due to the ionisation of −NH₂ groups from the modifier molecule, which changes the surface charge. Electrokinetic curves of the pigment composites changed considerably as a function of the type and concentration of the organic dye adsorbed.

Only SiO2 supports (unmodified and aminosilane‐grafted) and C.I. Basic Red 1, C.I. Basic Orange 14 or C.I. Mordant Red 3 dyes adsorbed on its surface were evaluated. Other dyes could also be studied.

Measurements of the zeta potential were used to characterise the stability of colloidal dispersions of paints or dyes and to control the stability of paints on storage and their performance on painting and drying.

The paper demonstrates that the measurements of zeta potential permit determination of the optimum conditions for the use of a given pigment. The finding of the change of the zeta potential of a given pigment and so, also its application properties as a result of different functional groups in the dye or the modifying agent molecules.

The purpose of this paper is to propose a new method of synthesis of CuO · SiO₂ oxide composite based on the reaction of precipitation from water solutions of sodium silicate and copper nitrate.

Solutions of sodium silicate and copper nitrate were used as substrates. The effects of direction of substrate supply, concentration, excess of reagents and temperature of precipitation on the physicochemical properties of the products were analysed.

A new method of synthesis of CuO · SiO₂ oxide composite based on a precipitation reaction is proposed.

Only sodium silicate and copper nitrate solutions were used.

The CuO · SiO₂ oxide composite obtained can be used as blue pigment or polymer filler.

The paper determines optimum conditions of CuO · SiO₂ oxide composite precipitation to obtain products with desired physicochemical, dispersive and structural properties.