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1 – 10 of over 1000
Article
Publication date: 3 November 2014

X.R. Zhang, L.Z. Liu, J.F. Li, W.W. Cui and L. Weng

The key purpose of this study was to investigate the effects of different ultrasonic irradiation times on the wettability and other properties of the resulting water-based…

Abstract

Purpose

The key purpose of this study was to investigate the effects of different ultrasonic irradiation times on the wettability and other properties of the resulting water-based coating. The subject water-based coating was prepared using water-soluble polyester and amino resins by ultrasonic oscillation.

Design/methodology/approach

The coating was prepared by polymerising polyester and amino resins in water using ultrasonic oscillation. The coating was baked for 40 seconds at 350°C to coalesce and solidify the film. The contact angle, thermal stability and mechanical properties of the film, as well as the molecular weight (MW) and structure of the polyester resin, were determined.

Findings

The contact angle of the coating was found to decrease with ultrasonic irradiation; the mechanical properties and thermal stability were not altered when the irradiation time was longer than 5 hours. The MW of the polyester initially decreased then increased and stabilized with ultrasonic irradiation. The structure of polyester molecule and aggregated state of the solidified coating were not changed by ultrasonic irradiation.

Research limitations/implications

In the study reported here, the effects of different ultrasonic irradiation times were investigated. Results of this research could benefit in-depth understanding of the influence of ultrasonic treatment on polyester resins and polyester coatings and could further promote the development of water-based coatings.

Originality/value

The contact angle of the water-based coating decreased by mechanical means. The effects of ultrasound on microstructure and properties of the coating and resin were discussed in detail.

Details

Pigment & Resin Technology, vol. 43 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 4 January 2016

M.Y. Zhang, L.Z. Liu, L. Weng, W.W. Cui and K.S. Hui

– The aim of this study was to fabricate polyimide (PI)/Al2O3 composite films via surface modification and ion exchange techniques, and examine their properties.

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Abstract

Purpose

The aim of this study was to fabricate polyimide (PI)/Al2O3 composite films via surface modification and ion exchange techniques, and examine their properties.

Design/methodology/approach

The method involves hydrolyzing the PI film double surface layers in an aqueous potassium hydroxide (KOH) solution and incorporating aluminium ions (Al3+) into the hydrolyzed layers of the PI film via subsequent ion exchange, followed by a treatment of the Al3+-loaded PI films with an aqueous ammonia solution, which leads to the formation of Al(OH)3 in the surface-modified layers. After a final thermal annealing treatment in ambient air, the Al(OH)3 decomposes to Al2O3, and forms composite layers on both surfaces of the re-imidized PI film.

Findings

The PI/Al2O3 composite film obtained with a 6 hours of KOH treatment exhibited excellent thermal stability, good mechanical properties and better electric breakdown strength and corona-resistance properties than the pristine PI film.

Practical implications

The method for obtaining the composite films in this paper is worth consideration, but additional research will be needed. Furthermore, this method is of general importance for the fabrication of composite PI films with tailored properties.

Originality/value

This study showed that surface modification and ion-exchange techniques are powerful methodologies for the fabrication of PI/Al2O3 composite films.

Details

Pigment & Resin Technology, vol. 45 no. 1
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 29 October 2020

Dennis Lu-Chung Weng, Lu-Huei Chen and Ching-Hsing Wang

The main purpose of this study is to reveal how the China factor influences Taiwan voters' evaluations of the two major parties across elections and generations. We…

Abstract

Purpose

The main purpose of this study is to reveal how the China factor influences Taiwan voters' evaluations of the two major parties across elections and generations. We contend that 1) elderly Taiwan voters may take the China factor more seriously than younger cohorts, and 2) China factor may be weighted differently depending on the levels of elections. More importantly, we argue that the China factor is tangled with voters' partisanship.

Design/methodology/approach

Data gathered from 2008 to 2014 Taiwan's Election and Democratization Study (TEDS) enable in investigating the influence of the China factor on Taiwan people's vote choices in the two local and two presidential elections. To answer the research question, this study applies issue voting theory and the seemingly unrelated regression (SUR) employed for empirical investigations.

Findings

The findings of this study provide empirical evidence on how political generations have changed their reactions to China in Taiwan's elections. The fundamental variables, party identification and the China issue are still very important and cannot be disregarded. Specifically, the China factor played a quite influential role in the Democratic Progressive Party (DPP) supporters' voting decisions regardless of their generations, whereas its effect on the Kuomintang (KMT) supporters' voting decisions varies depending on electoral contexts and generations.

Originality/value

While some scholars might suspect that the single item is not sufficient to be an effective predictor of vote choice, we contend that the China factor is definitely the most significant component in Taiwan's elections, especially when it is tangled with partisanship. The SUR approach in this study confirms that partisanship and the China factor cannot be viewed separately.

Details

Asian Education and Development Studies, vol. 11 no. 2
Type: Research Article
ISSN: 2046-3162

Keywords

Article
Publication date: 4 August 2021

Feng Gao, Xiaorui Zhang, Ling Weng, Yujun Cheng and Jiahao Shi

Phenolic epoxy vinyl ester resin (PEVER) is an advanced resin matrix, which has excellent heat resistance, electrical insulation. However, the brittleness and poor…

Abstract

Purpose

Phenolic epoxy vinyl ester resin (PEVER) is an advanced resin matrix, which has excellent heat resistance, electrical insulation. However, the brittleness and poor toughness of its curing product limited its application, so this paper aims to modify the PEVER with hyperbranched polyimide (HBPI), so as to enhance the toughness, heat resistance and dielectric properties of PEVER.

Design/methodology/approach

Hexamethylene diisocyanate trimer was used as the central reactant. Methyl tetrahydrophthalic anhydride was used as the branching unit, stannous octoate was used as the catalyst and hydroquinone was prepared as the inhibitor. Then, the hyperbranched structure of HBPI was characterized by Fourier transform infrared spectrometer and 13C-NMR. Next, PEVER was mixed with different contents of HBPI, and then the authors tested its curing product.

Findings

It is found that with the addition of HBPI, the free volume of the system was increased and the content of polar groups was decreased in each unit space, so the dielectric constant (ε) and the dielectric loss (tanδ) were decreased. In addition, PEVER could be well toughened by HBPI and the thermal stability of PEVER was improved.

Originality/value

HBPI has excellent heat resistance. The addition of hyperbranched polymer increases the free volume of the system so it can slow down the transfer of stress and its nearly circular structure can absorb the impact energy from all directions. Moreover, an appropriate amount of free volume can decrease the dielectric constant of PEVER by reducing the content of polar groups.

Details

Pigment & Resin Technology, vol. 51 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 6 December 2018

Zhen Yan, Dong Jiang, Xiaoming Gao, Can Zhang, Ming Hu, Dapeng Feng, Jiayi Sun, Lijun Weng and Chao Wang

This paper aims to study the tribological behavior of the WS2/oil-impregnated porous polyimide (PPI) solid/liquid composite system, in which both PFPE (perfluoropolyether…

Abstract

Purpose

This paper aims to study the tribological behavior of the WS2/oil-impregnated porous polyimide (PPI) solid/liquid composite system, in which both PFPE (perfluoropolyether) and SiCH (silahydrocarbons) oils with different hydrocarbon chains were used, respectively. Lubricating mechanism of the composite system was also explored.

Design/methodology/approach

The tribological behaviors of the WS2 films against the PPI cylindrical pins before and after immersing oil were evaluated under different loads by a reciprocating-type ball-on-disc tribometer.

Findings

The composite system exhibited the low and stable friction coefficient after the running-in stage, and the lubricant oil played a positive effect. It was found that the WS2/PFPE composite system exhibited more excellent lubricating property, although sole SiCH far exceeds PFPE in lubrication. The abnormal phenomenon mainly resulted from the influence of the oil amount. XRD results on the wear track surfaces indicated that PFPE and SiCH oils with different hydrocarbon chains were likely to preferentially adsorb to the edge plane and basal plane of the WS2 crystals, respectively.

Originality/value

In previous studies, liquid lubricants were directly dripped or spin-coated on the solid lubricant surface. Based on its potential advantage in application, the tribological behavior and mechanism of the solid lubricating film/oil-impregnated PPI composite system were investigated in this study.

Details

Industrial Lubrication and Tribology, vol. 71 no. 3
Type: Research Article
ISSN: 0036-8792

Keywords

Content available
Book part
Publication date: 2 August 2022

Christopher Ansell, Eva Sørensen and Jacob Torfing

Abstract

Details

Co-Creation for Sustainability
Type: Book
ISBN: 978-1-80043-798-2

Book part
Publication date: 25 September 2020

Letife Özdemir

Purpose: Through globalization, financial markets have become more integrated and their tendency to act together has increased. The majority of the literature states that…

Abstract

Purpose: Through globalization, financial markets have become more integrated and their tendency to act together has increased. The majority of the literature states that there is a cointegration between developed and emerging markets. How do positive or negative shocks in developed markets affect emerging markets? And how do positive or negative shocks in emerging markets affect developed markets? For this reason, the aim of the study is to investigate the asymmetric causality relationship between developed and emerging markets with Hatemi-J asymmetric causality test.

Design/methodology/approach: In this study, the Dow Jones Industrial Average (DJIA) index was used to represent developed markets and the Morgan Stanley Capital International (MSCI) Emerging Market Index was used to represent emerging markets. The asymmetric causality relationship between the DJIA Index and the MSCI Emerging Market Index was investigated using monthly data between January 2009 and April 2019. In the first step of the study, the Johansen Cointegration Test was used to determine whether there is a cointegration between the markets. In the next step, the Hatemi-J asymmetric causality test was applied to see the asymmetric causality relationship between the markets.

Findings: There is a weak correlation between developed and emerging markets. This result is important for international investors who want to diversify their portfolios. As a result of the Johansen Cointegration Test, it was found that there is a long-term relationship between the MSCI Emerging Market Index and the DJIA Index. Therefore, investors who make long-term investment plans should not forget that these markets act together and take into account the causal relationship between them. According to the asymmetric causality test results, a unidirectional causality relationship from the MSCI Emerging Market Index to the DJIA Index was determined. This causality shows that negative shocks in the MSCI Emerging Market Index have positive effects on the DJIA Index.

Originality/value: This study contributes to the literature as it is one of the first studies to examine the asymmetrical relationship between developed and emerging markets. This study is also useful in predicting the short- and long-term relationship between markets. In addition, this study helps investors, portfolio managers, company managers, policymakers, etc., to understand the integration of financial markets.

Details

Uncertainty and Challenges in Contemporary Economic Behaviour
Type: Book
ISBN: 978-1-80043-095-2

Keywords

Article
Publication date: 16 September 2013

Maizaitulaidawati Md Husin and Asmak Ab Rahman

This paper aims to examine the basic determinants of consumers intention to participate in family takaful scheme using decomposed theory of planned behaviour (DTPB) and…

5028

Abstract

Purpose

This paper aims to examine the basic determinants of consumers intention to participate in family takaful scheme using decomposed theory of planned behaviour (DTPB) and identifying relevant factors may be moderate the relationship.

Design/methodology/approach

A comprehensive review of the DTPB literature is undertaken, with a particular focus on contribution to family takaful scheme.

Findings

The review finds that intention toward participating in family takaful scheme is are not only affected by attitude, subjective norm and perceived behavioural control but also influence by moderating factors like demographic variables, consumer knowledge, situational factors and consumer level of religiosity. Inhibiting factors related to insurance and takaful purchase is also highlighted.

Originality/value

Such an extensive review on identifying relevant factors to participate in takaful using DTPB has not been done before. The paper will be useful to researchers, professionals and others concerned with family takaful to understand the importance factors in participating in family takaful scheme.

Details

Journal of Islamic Marketing, vol. 4 no. 3
Type: Research Article
ISSN: 1759-0833

Keywords

Article
Publication date: 8 February 2016

Maizaitulaidawati Md Husin and Asmak Ab Rahman

The purpose of this paper is to apply theory of planned behaviour (TPB) in predicting consumer intention to participate in takaful. One area of concern for takaful…

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Abstract

Purpose

The purpose of this paper is to apply theory of planned behaviour (TPB) in predicting consumer intention to participate in takaful. One area of concern for takaful operators is the untapped Islamic insurance (takaful) market and lower market share compared to conventional insurance counterparts. It is possible that the application of the TPB could shed some light on the problem and possibly offer some assistance to the takaful operators.

Design/methodology/approach

Interrelationships among attitudes, subjective norm, perceived behavioural control and purchase intentions in regard to takaful products participation were examined within a framework of the theory of planned behaviour. A model and series of propositions are developed. The propositions are open to empirical verification and can form the basis for a research stream on takaful participation.

Findings

In identifying factors influencing takaful participation, TPB is used and the model incorporates certain individual factors that are likely to influence intentions towards takaful participation. The model proposes that individual factors such as awareness, knowledge and exposure have impacts on takaful participation.

Originality/value

This study provides insights for a previously unaddressed takaful participation among potential consumers. Prior work on determining participation of takaful has not applied TPB in an effort to understand the phenomenon.

Details

Journal of Islamic Accounting and Business Research, vol. 7 no. 1
Type: Research Article
ISSN: 1759-0817

Keywords

Article
Publication date: 7 March 2016

Maizaitulaidawati Md Husin, Noraini Ismail and Asmak Ab Rahman

This paper aims to address the influence of mass media (MM) and word of mouth (WOM) on subjective norm (SN) and the intentions to purchase a family takaful scheme among…

5059

Abstract

Purpose

This paper aims to address the influence of mass media (MM) and word of mouth (WOM) on subjective norm (SN) and the intentions to purchase a family takaful scheme among Muslim Malaysians.

Design/methodology/approach

Data were collected from 384 Muslim consumers in Kuala Lumpur, Malaysia, using a convenience sampling approach. The hypotheses were tested by applying structural equation modelling.

Findings

The results revealed that MM and WM were able to influence SN. In addition, the results also found that SN significantly influences intentions to purchase a family takaful scheme.

Practical implications

By examining MM and WM on SN, the study validated the importance of both constructs in affecting consumers’ SN and purchase intention. This study would be useful for takaful operators, as the findings would help them to formulate strategies for promotional activities.

Originality/value

This paper empirically justifies the relationship between MM and WM on SN and purchase intention of family takaful schemes in an integrated model.

Details

Journal of Islamic Marketing, vol. 7 no. 1
Type: Research Article
ISSN: 1759-0833

Keywords

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