Yilu Gong, Tantan Shao, Xiuming Wang, Xin Zhang, Zhijuan Sun and Lijun Chen
Fluorine and silicon materials have received the keen attention of many researchers because of their water repellency and low surface free energy. The purpose this study was to…
Abstract
Purpose
Fluorine and silicon materials have received the keen attention of many researchers because of their water repellency and low surface free energy. The purpose this study was to prepare vinyl acetate (VAc)-vinyl ester of neodecanoic acid (VeoVa 10) copolymer latex modified with fluorine and silicone monomer, which is emulsified with the novel surfactants of disodium laureth sulfosuccinate (MES) and octylphenol polyoxyethylene ether (OP-10).
Design/methodology/approach
A series of modified latices containing fluorine-silicon have been prepared by semi-continuous seeded emulsion polymerisation of mixed monomers of VAc, VeoVa10, hexafluorobutylmethacrylate (HFMA) and vinyltriethoxysilane (VTES) and emulsified by novel surfactants of MES and OP-10.
Findings
The optimum conditions for preparing the modified latex is as follows: the amount of the surfactant was 4.0 Wt.% and the mass ratio of the anionic and nonionic surfactant was 3:1; the dosage of initiator was 0.4 Wt.% and the mass ratio of the main monomer was 3:1; and the amounts of VTES and HFMA were 2.0 and 6.0 Wt.%, respectively. In comparison with the conventional latex, the hydrophobicity of latex film was improved further.
Originality/value
The modified p (VAC-VeoVa) latex is prepared via semi-continuous seeded emulsion polymerisation, which is emulsified with the novel mixed surfactants of MES and OP-10. There are two main innovations. One is that the novel p (VAC-VeoVa) latex containing fluorine-silicon is prepared successfully. The other is that the emulsifier is composed of the novel mixed surfactants of MES and OP-10.
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Yilu Gong, Tantan Shao and Lijun Chen
Fluorine materials have received the keen attention of many researchers because of their water repellency and low surface free energy. The purpose of this paper is to prepare…
Abstract
Purpose
Fluorine materials have received the keen attention of many researchers because of their water repellency and low surface free energy. The purpose of this paper is to prepare fluorine-containing soap-free acrylic emulsion, which sodium allyoxypropyl hydroxypropyl sulfonate (COPS-1) and anionic emulsifier sodium a-alkenyl sulfonate (a-AOS) were combined as polymerizable emulsifier, and undecylenic acid (UA) and dodecafluoroheptyl methacrylate(DFMA) were introduced as functional monomer.
Design/methodology/approach
The fluorinated polyacrylate emulsion was successfully prepared by semi-continuous seed emulsion polymerization, wherein the main monomers were methyl methacrylate (MMA) and butyl methacrylate (BA), and the initiator was potassium persulfate (KPS). Sodium alloxypropyl sulfonate (COPS-1) and an anionic emulsifier sodium a-alkenyl sulfonate (a-AOS) were compounded as a polymerizable emulsifier. Besides, undecylenic acid (UA) and dodecafluoroheptyl methacrylate (DFMA) were introduced as the functional monomers.
Findings
The optimum recipe of preparing the modified latex is as follows: the amount of emulsifier was 4%, the ratio of emulsifier (COPS-1: AOS) was 3: 1, and the content of initiator was 0.6%. In this case, the conversion rate of acrylic polymer emulsion was high and the polymerization stability was good. When the amount of monomer UA was 2% and the amount of DFMA was 4%, the overall performance of the emulsion was the best.
Originality/value
The fluorine-containing soap-free acrylic emulsion is prepared via semi-continuous seeded emulsion polymerisation, which sodium allyoxypropyl hydroxypropyl sulfonate (COPS-1) and anionic emulsifier sodium a-alkenyl sulfonate (a-AOS) were combined as polymerizable emulsifier, and undecylenic acid (UA) and dodecafluoroheptyl methacrylate (DFMA) were introduced as functional monomer. There are two main innovations. One is that the fluorine-containing soap-free acrylic emulsion is prepared successfully. The other is that the undecylenic acid is introduced as functional monomer.
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This study aims to examine the effects of local tournament incentives on environmental, social and governance (ESG) disclosure and the quality of such disclosures among Chinese…
Abstract
Purpose
This study aims to examine the effects of local tournament incentives on environmental, social and governance (ESG) disclosure and the quality of such disclosures among Chinese A-share listed companies. Furthermore, it seeks to investigate the moderating roles of CEO duality, institutional investors’ shareholding and product market competition in this relationship.
Design/methodology/approach
This study uses a quantitative approach, and data from A-share listed companies in China spanning from 2012 to 2021. To test the proposed hypotheses, the authors conduct hierarchical regression analysis along with a series of robustness tests to ensure the validity of our findings.
Findings
The findings of this study indicate that local tournament incentives have a positive impact on companies’ propensity to disclose ESG information, yet they negatively influence the quality of these disclosures. Additionally, the presence of CEO duality and product market competition attenuate this relationship, whereas the shareholding of institutional investors serves to strengthen it.
Practical implications
This study’s findings can aid policymakers and regulators in China and other emerging economies in policies that promote high-quality ESG information disclosure, taking into account local tournament incentives. Furthermore, the study underscores the importance of maintaining robust corporate governance structures within firms to ensure that CEOs’ self-serving motivations do not undermine ESG disclosure.
Originality/value
This study adds to the ongoing discourse on the significance of ESG disclosure in emerging economies by analyzing the influence of executive promotion incentives on ESG disclosure from an external labor market standpoint. By exploring the potential self-serving motivations of CEOs in promoting ESG values and practices within organizations, this paper addresses a gap in the existing literature.
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Since China’s “opening-up” in the late 1970s, Singapore has played a major role in enhancing China’s engagement with the world, especially in economic terms. This traditional…
Abstract
Purpose
Since China’s “opening-up” in the late 1970s, Singapore has played a major role in enhancing China’s engagement with the world, especially in economic terms. This traditional relationship is well manifested in the third government-to-government (G–G) project under the BRI, which is known as the Chongqing Connectivity Initiative (CCI). The purpose of this paper is to address the following question: despite Singapore’s initial reluctance to agree on a third G–G project with China, why did Singapore eventually decide to join the CCI?
Design/methodology/approach
This paper draws on archives of over 700 Chinese language media reports and over 400 English language media reports, as well as private interactions with scholars interested in Sino-Singapore relations and with both sides’ officials in charge of the CCI project.
Findings
The paper finds that it is the goal of connecting the region, along with the need to maintain Singapore’s relevance to China and the regional economy that led to Singapore’s participation in the third G–G project. This paper also uses this case to analyse the changes that are taking place in the bilateral economic relations.
Originality/value
Despite wide media coverage, op-ed commentaries and respective government statements, there are a limited number of academic studies on the rationale of the third G–G project and contemporary Sino-Singapore relations in the literature. The scholarship has not addressed the rationale for Singapore’s changing attitude towards CCI and the manner in which the CCI has improved cooperation (or upgraded cooperation to a broader and regional level).
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This paper intends to provide a thematic literature review of the scholarly research articles orbiting the Sino–African education cooperation and exchange, published between 2005…
Abstract
Purpose
This paper intends to provide a thematic literature review of the scholarly research articles orbiting the Sino–African education cooperation and exchange, published between 2005 and 2022.
Design/methodology/approach
The methodology used in this paper is qualitative in nature with a thematic approach. The author used content analysis techniques to spotlight the major themes of the topic studied. The author selected the papers and theses, based on their heuristic capacity, from two major databases for the English and Chinese literature: Web of Science and CNKI. The selection process resulted in 60 high-quality peer-reviewed articles and theses. Another 30 research articles and theses were used as supplementary resources.
Findings
The literature concentrates on six points: the historical development, the nature of the exchange, the frameworks of the cooperation, vocational training and knowledge transfer, African students in China and their experiences, and education cooperation and soft power. However, research tends to be somewhat polemical rather than an academic debate between Chinese researchers and their western peers. Therefore, empirical studies beyond the geopolitical preoccupations and the “YEA” or “NAY” to the Sino–African education exchange are critically needed.
Practical implications
The implications of this study go beyond the east/west or developed/developing world rhetoric and focus more on sustainable educational development on a global scale. Understanding how the literature on the Sino–African education engagement is shaping, provides valuable insights into international education in the global south. It can also be implied to approach educational engagement with other destinations such as India, Türkiye and Brazil.
Originality/value
This thematic literature review concentrates on the educational aspect of Sino–African relations. It compares English and Chinese peer-reviewed scholarly articles and theses on China–Africa educational engagement and has heuristic implications for sustainable educational development globally.