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1 – 10 of over 2000
Article
Publication date: 1 August 2007

Fátima Esteves and Helena Alonso

Chemical treatment methods are most often used nowadays for polymer surface modification; however, new technologies are now considered, especially in physical treatment methods…

Abstract

Chemical treatment methods are most often used nowadays for polymer surface modification; however, new technologies are now considered, especially in physical treatment methods, as laser technologies. Infra-red lasers, like CO2, appear to be advantageous due to their large beam size, high efficiency, easy operation, use of non-toxic gases and low cost. However, they have been less used than others for surface treatment of polymers, possibly due to the thermal damage effects caused by infra-red radiation. This shortcoming can be overcome by the use of pulsed lasers. CO2 pulsed laser can be considered as a non-contact and environmental-friendly treatment technique for the modification of the surface of polymers. Surface morphological modifications can be produced, resulting in changes in the physical and chemical properties of the materials, such as water absorption and dyeing. In this work, polyester and polyamide fabrics were treated with a CO2 pulsed laser and then dyed with different commercial dyes. Dyeing properties were investigated and changes in the dye ability of laser treated fibres are expected. Laser treatment created certain roughness on the fibre surface, resulting in an increase of the overall surface area and a subsequent enhancement of dye adsorption.

Details

Research Journal of Textile and Apparel, vol. 11 no. 3
Type: Research Article
ISSN: 1560-6074

Keywords

Article
Publication date: 13 June 2016

Binnur Sagbas

The aim of this study is to determine the effect of argon plasma surface modification on tribological properties of conventional ultra-high molecular weight polyethylene (UHMWPE…

Abstract

Purpose

The aim of this study is to determine the effect of argon plasma surface modification on tribological properties of conventional ultra-high molecular weight polyethylene (UHMWPE) and vitamin E-blended UHMWPE. In previous studies, some researchers conducted a study on argon plasma surface modification of UHMWPE, but there is no study about argon plasma surface modification of VE-UHMWPE. So another objective of this paper is to compare the results for both the material groups.

Design/methodology/approach

UHMWPE and vitamin E-blended UHMWPE sample surfaces were modified by microwave-induced argon plasma to increase tribological properties of the materials. The modified surfaces were evaluated in terms of wettability and wear behavior. Wettability of the surfaces was determined by contact angle measurements. Wear behavior was examined by ball-on-disc wear tests under lubrication with 25 per cent bovine serum.

Findings

Argon plasma surface modification enhanced the wear resistance and surface wettability properties of conventional UHMWPE and VE-UHMWPE. Wear factor of argon plasma-treated samples reduced, but for VE-UHMWPE samples, this reduction was not as high as the conventional UHMWPE’s wear factor.

Originality/value

In previous studies, some researchers have studied on argon plasma surface modification of UHMWPE, but there is no study about argon plasma surface modification of VE-UHMWPE.

Details

Industrial Lubrication and Tribology, vol. 68 no. 4
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 24 July 2023

Upendra S. Gupta, Sudhir Tiwari and Uttam Sharma

The incompatibility of natural fibers with polymer matrices is one of the key obstacles restricting their use in polymer composites. The interfacial connection between the fibers…

Abstract

Purpose

The incompatibility of natural fibers with polymer matrices is one of the key obstacles restricting their use in polymer composites. The interfacial connection between the fibers and the matrix was weak resulting in a lack of mechanical properties in the composites. Chemical treatments are often used to change the surface features of plant fibers, yet these treatments have significant drawbacks such as using substantial amounts of liquid and chemicals. Plasma modification has recently become very popular as a viable option as it is easy, dry, ecologically friendly, time-saving and reduces energy consumption. This paper aims to explore plasma treatment for improving the surface adhesion characteristics of sisal fibers (SFs) without compromising the mechanical attributes of the fiber.

Design/methodology/approach

A cold glow discharge plasma (CGDP) modification using N2 gas at varied power densities of 80 W and 120 W for 0.5 h was conducted to improve the surface morphology and interfacial compatibility of SF. The mechanical characteristics of unmodified and CGDP-modified SF-reinforced epoxy composite (SFREC) were examined as per the American Society for Testing and Materials standards.

Findings

The cold glow discharge nitrogen plasma treatment of SF at 120 W (30 min) enhanced the SFREC by nearly 122.75% superior interlaminar shear strength, 71.09% greater flexural strength, 84.22% higher tensile strength and 109.74% higher elongation. The combination of improved surface roughness and more effective lignocellulosic exposure has been responsible for the increase in the mechanical characteristics of treated composites. The development of hydrophobicity in the SF had been induced by CGDP N2 modification and enhanced the size of crystals and crystalline structure by removing some unwanted constituents of the SF and etching the smooth lignin-rich surface layer of the SF particularly revealed via FTIR and XRD.

Research limitations/implications

Chemical and physical treatments have been identified as the most efficient ways of treating the fiber surface. However, the huge amounts of liquids and chemicals needed in chemical methods and their exorbitant performance in terms of energy expenditure have limited their applicability in the past decades. The use of appropriate cohesion in addition to stimulating the biopolymer texture without changing its bulk polymer properties leads to the formation and establishment of plasma surface treatments that offer a unified, repeatable, cost-effective and environmentally benign replacement.

Originality/value

The authors are sure that this technology will be adopted by the polymer industry, aerospace, automotive and related sectors in the future.

Details

Pigment & Resin Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 28 August 2007

Andy Cobley and Tim Mason

This paper sets out to give an introduction to sonochemistry and the effects brought about by the application of ultrasound that might be useful in surface modification; and to…

Abstract

Purpose

This paper sets out to give an introduction to sonochemistry and the effects brought about by the application of ultrasound that might be useful in surface modification; and to show the feasibility of sonochemical surface modification in water on a range of materials employed in electronic manufacturing.

Design/methodology/approach

Ultrasound was applied through DI water for the surface modification of four materials: a ceramic, a polyphenylene ester (polystyrene polymer (Noryl HM4025)), an acrylonitrile‐butadiene‐styrene/polycarbonate (ABS/PC‐Cycolac S705), and an FR4 laminate (Isola Duraver 104). The efficacy of the treatment was determined by weight loss, scanning electronic microscopy, contact angle and roughness.

Findings

Ceramic and Noryl materials can be surface modified sonochemically in DI water. Weight loss results suggested that, this was also the case for the Duraver laminate but the ABS/PC substrate was least affected by treatment in an ultrasonic field under these benign processing conditions.

Originality/value

Traditional “wet” surface modification techniques often use hazardous chemistry, high‐process temperatures, copious rinsing and long dwell times. This research programme addresses these issues by evaluating sonochemical surface modification techniques with the objective of producing a one‐step process using benign chemistry at lower temperature with less rinsing.

Details

Circuit World, vol. 33 no. 3
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 22 May 2009

X. Jiang, J. Gu, X. Bai, L. Lin and Y. Zhang

The purpose of this paper is to investigate in detail the effects of acid treatment on multi‐walled carbon nanotubes (MWNTs), which could find a variety of applications in…

Abstract

Purpose

The purpose of this paper is to investigate in detail the effects of acid treatment on multi‐walled carbon nanotubes (MWNTs), which could find a variety of applications in coatings and composites.

Design/methodology/approach

A number of analytical techniques, including Fourier transform infrared spectroscopy (FT‐IR), X‐ray photoelectron spectroscopy (XPS), Raman spectroscopy (Raman), and scanning electron microscopy (SEM), were employed to assess the effects of acid treatment on MWNTs.

Findings

It was found that desirable modifications to MWNTs occurred after acid treatment. Thus, carboxylic acid groups were introducing on to the surface of MWNTs. It was also found that both chemical and physical properties of MWNTs could be modified/altered.

Practical implications

The investigation established a method to modify MWNTs via acid treatment and the effects of such a treatment on MWNTs in detail. The modified MWNTs can be used for various applications and further modifications. The acid treated and the further modified MWNTs can be dispersed into polymers to prepare polymer/MWNTs composite materials and composite surface coatings. Some properties of the resulting composites were improved by the dispersed MWNTs, giving excellent mechanical, electrical, thermal and magnetic properties.

Originality/value

The finding on the effects of acid treatment on MWNTs, supported by detailed FT‐IR, XPS, Raman and SEM data, would be of interest to the field. The modification technique provided a route to further modification of carbon nanotubes. The acid treated and the further modified MWNTs are useful for preparation of polymer/MWNTs composite materials and composites surface coatings with improved mechanical, electrical, thermal and magnetic properties.

Details

Pigment & Resin Technology, vol. 38 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 December 1994

S M Tavakoli

Examines the use of power beams to prepare surfaces prior to adhesivebonding. Describes the current surface treatments available and discussestheir limitations. Outlines how power…

184

Abstract

Examines the use of power beams to prepare surfaces prior to adhesive bonding. Describes the current surface treatments available and discusses their limitations. Outlines how power beam techniques for surface modification of polymeric and metallic adherends has the potential to overcome many of these problems. Also looks at the emerging technology of using radiation‐curable adhesives based on ultraviolet, visible light and electron beams, which have the advantages of fast rates of cure, improved quality of finished products and the absence of any volatile organic compounds.

Details

Assembly Automation, vol. 14 no. 4
Type: Research Article
ISSN: 0144-5154

Keywords

Article
Publication date: 11 January 2008

H. Satapathy and A.K. Banthia

The purpose of this paper is to synthesise, characterise and study polymerisation kinetics of novel 4‐nonylphenylmethacrylate (NPMA) polymer.

Abstract

Purpose

The purpose of this paper is to synthesise, characterise and study polymerisation kinetics of novel 4‐nonylphenylmethacrylate (NPMA) polymer.

Design/methodology/approach

New methacrylic monomer, 4‐NPMA with a pendant nonylphenyl group was synthesised and characterised using various characterisation techniques. The free radical polymerisation kinetics study was done with the help of differential scanning calorimetry data.

Findings

The average heat of polymerisation (ΔHp) was found to be 685.43 J/g. Activation energy (Ea) of 95.86 kJ mol−1 and frequency factor of (A) 3.4 × 104 min−1 was obtained using Kissinger method. The thermogravimetric analysis of the polymer in nitrogen reveals that it possesses very good thermal stability in comparison to alkyl methacrylates due to presence of pendant nonylphenyl group.

Research limitations/implications

New methacrylic monomer, 4‐NPMA was synthesised by reacting nonylphenol dissolved in methyl ethyl ketone (MEK) with methacryloyl chloride in the presence of triethylamine as a base. Polymerisation of 4‐NPMA was carried out in MEK using benzoyl peroxide (BPO) as initiator under nitrogen atmosphere. The kinetics study of NPMA monomer with 1.1 wt% BPO was reported for evaluation of kinetic parameters by employing the Kissinger equation.

Practical implications

This is a simple and easy method of modification of methacrylate ester with phenyl groups to obtain a polymer of enhanced properties.

Originality/value

This is a novel method for enhancing the thermal as well as surface adhesion properties of methacrylate polymers which finds several applications in surface coatings and adhesives.

Details

Pigment & Resin Technology, vol. 37 no. 1
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 13 August 2018

Jizhi Zhang and Xiankai Jiang

The purpose of this paper is to synthesize and characterize a series of alicyclic two-component waterborne polyurethane (2K-WPU) which is composed of non-ionic polyisocyanate…

Abstract

Purpose

The purpose of this paper is to synthesize and characterize a series of alicyclic two-component waterborne polyurethane (2K-WPU) which is composed of non-ionic polyisocyanate aqueous dispersion and hydroxyl aqueous dispersion.

Design/methodology/approach

The appearances of aqueous dispersions and 2K-WPU films were observed by photographs. The micromorphology of alicyclic polyisocyanate aqueous dispersion was examined by scanning electron microscopy (SEM). The molecule structures of WPU were studied by Fourier transform infrared (FTIR). The effect of NCO:OH molar ratio of two components and trimethylolpropane (TMP) content on the thermal stability, mechanical and water resistance properties of 2K-WPU films was studied.

Findings

It was found by SEM that alicyclic polyisocyanate particles in aqueous dispersion showed a kind of spherical particle appearance, in which hydrophobic polyisocyanate was encapsulated by hydrophilic ether linkages segment. FTIR showed that WPU was polymerized through mixture of polyisocyanate component and hydroxyl component and increasing NCO:OH molar ratio of two components from 1.1:1 to 1.5:1 had increased the content of urea, urethane and allophanate of 2K-WPU films. Increasing NCO:OH molar ratio had improved the mechanical and thermal properties of the 2K-WPU film, but the water resistance of the 2K-WPU film increased first and then weakened. Increasing TMP contents from 1 to 0.75 mol for 1:5 system had improved the mechanical, thermal and water resistance properties of the 2K-WPU film.

Practical implications

The investigation established a method to prepare alicyclic 2K-WPU which is composed of non-ionic polyisocyanate aqueous dispersion and hydroxyl aqueous dispersion. The prepared 2K-WPU film could be applied in the field of waterborne surface coating, e.g. textile, wood and synthetic leather surfaces (Hasan et al., 2017; Akindoyo et al., 2016).

Originality/value

The paper established a method to synthesize alicyclic two-component 2K-WPU. The effect of NCO:OH molar ratio and TMP content on the thermal stability, mechanical and water resistance properties of 2K-WPU films were studied.

Details

Pigment & Resin Technology, vol. 47 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 8 November 2022

Abolfazl Zare

This study aims to enhance the dyeability of polyester fabrics with turmeric natural dyes through plasma and alkaline treatments. The aim is to achieve better color strength in…

Abstract

Purpose

This study aims to enhance the dyeability of polyester fabrics with turmeric natural dyes through plasma and alkaline treatments. The aim is to achieve better color strength in dyed samples without significant changes in their other properties. This is done while the weight loss is kept in a range with no considerable effect on those properties.

Design/methodology/approach

The surface of a poly(ethylene terephthalate) fabric was modified using oxygen plasma at a low temperature. The alkaline hydrolysis of that polyester fabric was also done through treating it with an aqueous sodium hydroxide (NaOH) solution. The untreated and treated polyester fabrics were studied for the changes of their physical characteristics such as weight loss, wetting behavior, strength loss, bending length, flexural rigidity and K/S and wash fastness. The samples were treated with plasma and sodium hydroxide and dyed with a turmeric natural dye.

Findings

In comparison to the untreated sample, the plasma-treated, alkaline-treated and plasma treatment followed by alkaline hydrolysis polyester experienced 9.3%, 68.6% and 102.3% increase in its color depth as it was dyed with a turmeric natural dye, respectively. The plasma treatment was followed by alkaline hydrolysis. The improvement in the color depth could be attributed to the surface modification.

Originality/value

In this paper, investigations were conducted of the separate effects of plasma treatment and alkaline hydrolysis as well as their synergistic effect on the dyeing of the polyester fabric with a natural dye obtained from turmeric.

Details

Pigment & Resin Technology, vol. 52 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 8 August 2018

Sainan Zhang and Xiankai Jiang

The purpose of this paper is to synthesize and characterize a series of two-component aromatic waterborne polyurethane (2K-WPU) which is composed of non-ionic and anionic…

Abstract

Purpose

The purpose of this paper is to synthesize and characterize a series of two-component aromatic waterborne polyurethane (2K-WPU) which is composed of non-ionic and anionic polyisocyanate aqueous dispersion and polyurethane polyol aqueous dispersion.

Design/methodology/approach

The polyisocyanate aqueous dispersion was synthesized through non-ionic and anionic hydrophilic modification procedures. The values of the hydrogen bonding index (HBI) and molecule structures of WPU were obtained by Fourier transform infrared (FTIR). The thermal, mechanical and water resistance properties of 2K-WPU films were investigated.

Findings

The appearance of non-ionic polyisocyanate aqueous dispersion and anionic polyisocyanate aqueous dispersion was colorless translucent pan blue and yellow opaque emulsions, respectively. FTIR not only showed that 2K-WPU was obtained from the polymerization of polyisocyanate component and polyhydroxy component by polymerization but also showed that the content of hydrogen bondings of anionic 2K-WPU (WPU 2) was higher than non-ionic 2K-WPU (WPU 1). The glass-transition temperature (Tg), storage modulus and water resistance of WPU 2 were higher than WPU1, whereas the thermal stability of WPU1 was better than WPU 2.

Practical implications

The investigation established a method to prepare a series of 2K-WPU which was composed of non-ionic or anionic polyisocyanate aqueous dispersion and polyurethane polyol aqueous dispersion. The prepared 2K-WPU film could be applied as substrate resin material in the field of waterborne coating.

Originality/value

The paper established a method to synthesize a series of 2K-WPU. The effect of HBI value and the molecule structure of soft segment on the thermal stability, mechanical and water resistance properties of 2K-WPU films were studied.

Details

Pigment & Resin Technology, vol. 47 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

1 – 10 of over 2000