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Article
Publication date: 5 March 2021

Emrah Uysal, Mustafa Çakir and Bülent Ekici

Traditional nanocomposite production methods such as in situ polymerization, melt blending and solvent technique, have some deficits. Some of these are non-homogeneous…

Abstract

Purpose

Traditional nanocomposite production methods such as in situ polymerization, melt blending and solvent technique, have some deficits. Some of these are non-homogeneous particle distribution, setup difficulties, time-consuming and costly. On the other hand, three-dimensional printing technology is a quite popular method. Especially, Stereolithography (SLA) printing offers some benefits such as fast printing, easy setup and smooth surface specialties. Furthermore, surface modification of Graphene Oxide (GO) and its effects on polymer nanocomposites are quite important. The purpose of this study is to examine the effect of surface modification of GO nanoparticles on the mechanical properties and morphology of epoxy acrylate (BisGMA/1,6 hexane diol diacrylate) matrix nanocomposites.

Design/methodology/approach

In this study, Ultraviolet (UV) curable end groups of synthesized resin were linked to functional groups of graphene oxide, which are synthesized by the Tour method, which is a kind of modified Hummer method. In addition, synthesized GO nanoparticle’s surfaces were modified by 3-(methacryloyloxy) propyl trimethoxysilane. Significant weight percentages of GO were added into the epoxy acrylate resin. Different Wt.% of modified graphene oxide/acrylate resins was used to print test specimens with SLA type three-dimensional printer.

Findings

Surface modification has a significant effect on tensile strength for graphene oxide nanoparticles contained composites. In addition, a specific trend was not observed for tensile test results of non-modified graphene oxide. The tendency of impact and hardness test finding were similar for both surfaces modified and non-modified nanoparticles. Finally, the distribution of particles was homogeneous.

Originality/value

This paper is unique because of the inclusion of both surface modifications of graphene oxide nanoparticles and SLA production of nanocomposites with its own production of three-dimensional printer and photocurable polymer resin.

Details

Rapid Prototyping Journal, vol. 27 no. 4
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 1 October 1999

Andrzej Krysztafkiewicz and Slawomir Binkowski

Surface of precipitated silica was modified with 3‐aminopropyltriethoxysilane. The optimum solvent was selected, in which the silane coupling agent was deposited on silica…

Abstract

Surface of precipitated silica was modified with 3‐aminopropyltriethoxysilane. The optimum solvent was selected, in which the silane coupling agent was deposited on silica surface. Basic physicochemical properties of the modified silica were estimated. Methods of evaluating silica surface modification extent were presented, taking advantage first of all of its altered hydrophilicity and of differences in condensation extent of surface silanol groups. The modified silica was used as adsorbent capable of trapping water soluble organic amines.

Details

Pigment & Resin Technology, vol. 28 no. 5
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 June 2003

A. Krysztafkiewicz, S. Binkowski, A. Kaczmarek and T. Jesionowski

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…

Abstract

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.

Details

Pigment & Resin Technology, vol. 32 no. 3
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 October 2000

Radosllaw Werner, Andrzej Krysztafkiewicz and Teofil Jesionowski

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…

Abstract

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.

Details

Pigment & Resin Technology, vol. 29 no. 5
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 7 November 2016

Lizhu Liu, Weiliang Li, Weiwei Cui, Xiaorui Zhang and Weng Ling

In this paper, boric acid was loaded on the surface of expandable graphite (EG), polyvinyl alcohol (PVA) and silane coupling agent (KH550) served as a bridge. The purpose…

Abstract

Purpose

In this paper, boric acid was loaded on the surface of expandable graphite (EG), polyvinyl alcohol (PVA) and silane coupling agent (KH550) served as a bridge. The purpose of this study was to improve the flame retardant properties of semi-rigid polyurethane, meanwhile, the mechanical properties of the foam got ameliorated.

Design/methodology/approach

PVA was dissolved in hot water. EG was added to this solution. After stirring for 0.5 h at 85°C in ultrasonic agitation, the system was put at room temperature to cool. The silane coupling agent KH550 was added dropwise into the solution system, stirring to fully hydrolyze. Boric acid was added into the system, placing it in an oven at 90°C to dry after filtration. Changing of flame retardant properties and mechanical properties of semi-rigid polyurethane adding modified EG were characterized.

Findings

The flame retardant performance of the foam with EG has been improved, whereas the tensile strength decreased with an increase in the content of EG. After adding modified EG, compared to semi-rigid polyurethane with EG, flame retardant performance and tensile strength of the foam improved.

Research limitations/implications

In the study reported here, the surface of EG was modified by boric acid. The modified EG was added into semi-rigid polyurethane foam. The flame retardant performance and tensile strength of the foam after adding modified EG were discussed. Results of this research could benefit in-depth study of the influence of adding modified EG to semi-rigid polyurethane. The study could promote the application of flame-retardant polyurethane foam.

Originality/value

The flame retardant performance and tensile strength of the semi-rigid polyurethane were improved by adding modified EG. The effects of modified EG on the flame retardant performance and tensile strength of semi-rigid polyurethane were discussed in detail.

Details

Pigment & Resin Technology, vol. 45 no. 6
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 10 May 2021

María V. Puc-Oxté and Máximo A. Pech-Canul

This paper aims to prepare highly hydrophobic films on aluminum AA3003 using myristic acid (MA) and evaluate its corrosion protection efficiency in a low-chloride solution.

Abstract

Purpose

This paper aims to prepare highly hydrophobic films on aluminum AA3003 using myristic acid (MA) and evaluate its corrosion protection efficiency in a low-chloride solution.

Design/methodology/approach

The aluminum surface was initially treated with boiling water to develop a porous nanostructure, and then surface modification was carried out in ethanolic solutions with different concentrations of MA. The surface morphology, wetting behavior and film composition were first characterized, and then, the corrosion behavior was evaluated with electrochemical techniques.

Findings

The best hydrophobicity and corrosion resistance were obtained with 50 mM of MA. For such concentration, a water contact angle of 140° and protective efficiency of 96% were achieved. A multilayer structure was revealed by scanning electron microscope and X-ray photoelectron spectroscopy.

Originality/value

The results of this work shed light on the anticorrosion performance of fatty acid self-assembled multilayers on the surface of Al–Mn alloys.

Details

Anti-Corrosion Methods and Materials, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 20 June 2017

N. Adhikary and B. Gurumoorthy

This paper aims to propose an automatic and direct method to manipulate global parameters of the object for prototyping and simulation, given an STL mesh model of a…

Abstract

Purpose

This paper aims to propose an automatic and direct method to manipulate global parameters of the object for prototyping and simulation, given an STL mesh model of a thin-walled object. Proposed method is useful in rapid prototyping, where changing the global parameters such as thickness, scaling local features or draft of walls of an STL mesh is often required. Presently, user needs to iterate over the cycle of modification of the computer-aided design (CAD) model and tessellating it to change the global parameters. The proposed algorithm eliminates the need for CAD model while manipulating those global properties, as it works directly with the mesh model.

Design/methodology/approach

Proposed algorithm automatically identifies walls and its thickness, and then, it extracts mid-surface from each wall. Global parameters are then modified by using these mid-surfaces.

Findings

Mesh directly modified and the mesh obtained by tessellating modified CAD model has same global properties; proposed method can also allow multiple parameters to be modified at the same time.

Research limitations/implications

Input STL model is assumed to be error-free, where models containing errors like self-intersection will lead to incorrect mid-surfaces. Present algorithm assumes that the mid-surface represent of the input STL model is a manifold surface.

Originality/value

A novel algorithm of directly manipulating global parameters of a thin-walled object in its STL mesh model is proposed. The paper also presents a novel method of extracting mid-surface representation from a thin-wall STL mesh.

Details

Rapid Prototyping Journal, vol. 23 no. 4
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 10 August 2018

Ming Qiu, Rui Zhang, Yingchun Li, Hui Du and Xiao Xu Pang

The MoS2/graphite composite coatings modified by La2O3 through spraying technique were successfully prepared on the inner rings of spherical plain bearings. As a…

Abstract

Purpose

The MoS2/graphite composite coatings modified by La2O3 through spraying technique were successfully prepared on the inner rings of spherical plain bearings. As a comparison, unmodified coatings were also prepared. This paper aims to study the La-modified MoS2/graphite composite coating experimentally and improve the tribological performance of self-lubricating spherical plain bearings.

Design/methodology/approach

The performance of La2O3 toward the friction coefficient, temperature rise and wear rate of the coatings was studied by a self-made tribo-tester under different swing cycles. And the texture, surface morphology and element composition of the coatings were characterized by scanning electron microscope, energy dispersive spectroscopy and X-ray diffractometry.

Findings

The additives La2O3 refined the coatings’ microstructure and improved the tribological properties of the coatings. The oxidation of Mo + 4 to Mo + 6 was effectively inhibited. And the amount of abrasive grains, peeling pits and local cracks on the coatings surface decreased and homogeneous lubricating films formed, which were attributed to the existence of La2O3. The wear mechanisms of unmodified coatings were severe abrasive wear, adhesive wear and delamination wear. However, it exhibited superior wear resistance of the La-modified coatings to unmodified coatings, presenting slight abrasive wear and adhesive wear. The service life of bearings was prolonged under the protection of the modified coatings.

Originality/value

The paper proposed a new modified MoS2/Graphite composite coating for the self-lubricating spherical plain bearings. The investigation on the friction, wear and temperature increase behaviors and the wear mechanisms of the coatings are beneficial to prolonging the service life of the self-lubricating spherical plain bearings.

Details

Industrial Lubrication and Tribology, vol. 70 no. 8
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 13 September 2011

Peter Greenwood and Borje Gevert

The purpose of this paper is to study methods of reacting the surface of the particles of silica sols with silanes, primarily gamma‐glycidoxypropyltrimethoxysilane (GPTMS…

Abstract

Purpose

The purpose of this paper is to study methods of reacting the surface of the particles of silica sols with silanes, primarily gamma‐glycidoxypropyltrimethoxysilane (GPTMS) and study some basic properties of the modified sols and the nature and structure of the silane groups attached to the particle surface.

Design/methodology/approach

The surface of the silica particles was modified by reacting the silica sols with aqueous solutions of silanes, chiefly GPTMS. The presence and structure of silane groups on the particle surface were established by Si‐NMR and C‐NMR, respectively.

Findings

Several silanes were studied but silica sols could be readily modified only with GPTMS and glycidoxypropylmethoxydiethoxysilane (GPMDES), most readily if the silanes were pre‐hydrolysed in water. Higher degrees of silylation were preferably done by continuous addition of silane. Lower degrees of modification can be achieved at room temperature by the stepwise addition of the silane solution. The silylation of the silica surface with GPTMS significantly reduces the number of charged surface groups and silanol groups. GPTMS binds covalently to the silica surface and the epoxy ring opens and transforms into a diol. Silica sols modified with GPTMS and GPMDES are stable toward aggregation.

Research limitations/implications

Only organo‐reactive silanes were studied.

Originality/value

This is the first work to study the modification by silanes of silica aquasols with high concentrations of silica. The silane modification can extend the use of silica to areas of applications previously inaccessible to silica sols.

Details

Pigment & Resin Technology, vol. 40 no. 5
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 October 2002

Teofil Jesionowski, Andrzej Krysztafkiewicz and Aleksandra Dec

In this study, titanium white was investigated, covered with aluminium oxide and silica. The titanium white was produced by Chemical Works Police S.A. under the catalogue…

Abstract

In this study, titanium white was investigated, covered with aluminium oxide and silica. The titanium white was produced by Chemical Works Police S.A. under the catalogue symbol of R‐210. Surface of titanium white was modified with silane coupling agents, such as 3‐methacryloxypropyltrimethoxysilane (A‐174), vinyltrimethoxysilane (U‐611) and N‐2‐(aminoethyl)‐3‐aminopropyltrimethoxysilane (U‐15D). The unmodified and the modified titanium white was subjected to physicochemical analysis. Moreover, tests were performed aiming at defining morphology, surface structure, and dispersion of the particles as related to, first of all, the type of applied modifier. Product evaluation took advantage of modern investigative techniques, including SEM and DLS. Modified and unmodified titanium whites were applied as pigments in acrylic paints. The modified Titanium dioxide in particular improved strength and utility properties of studied paints.

Details

Pigment & Resin Technology, vol. 31 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

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