Dawid J. D'Melo, Anagha S. Sabnis, Mohan A. Shenoy and Mukesh S. Kathalewar
The purpose of this paper is to evaluate the efficiency of acrylated guar gum (AGG) as an additive in alkyd resin for improved mechanical properties and to optimize the results of…
Abstract
Purpose
The purpose of this paper is to evaluate the efficiency of acrylated guar gum (AGG) as an additive in alkyd resin for improved mechanical properties and to optimize the results of such an addition.
Design/methodology/approach
For studying the effect of AGG on coating properties, guar gum was modified to various degrees of esterification and various compositions of alkyd systems were made by incorporating different concentrations of AGG. The mechanical and solvent absorption of the unmodified and modified alkyd systems were characterized.
Findings
The incorporation of AGG into alkyd coating showed significant improvement of mechanical properties over the unmodified one. The modification caused an additional crosslink site through its unsaturation which led to increased crosslink density without phase separation of additive from the alkyd system which was confirmed by SEM scans.
Research limitations/implications
The reactive additive, AGG used in the present study was synthesised using acryloyl chloride. Besides, it could also be synthesised from methacryloyl chloride and the effect of methyl substitution on water and solvent absorption could be studied.
Practical implications
The method developed provided a simple and practical solution to improving the mechanical properties of alkyd coatings.
Originality/value
The method for enhancing mechanical properties of cured alkyd system was novel and could find numerous applications in surface coatings.
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The purpose of this paper is to study the effect of acrylated guar gum (GG) compared with GG in acrylic emulsions with reference to its viscosity, film properties such as…
Abstract
Purpose
The purpose of this paper is to study the effect of acrylated guar gum (GG) compared with GG in acrylic emulsions with reference to its viscosity, film properties such as mechanical strength, weathering properties and clarity.
Design/methodology/approach
The acrylate derivatives were synthesised and characterised and then incorporated in acrylic emulsions and their rheology studied. Films were analysed for their clarity and mechanical properties. The films were then subjected to UV radiation and the influence of these additives on the weathering properties was studied.
Findings
The viscosity of acrylated GGs in emulsions was lower than that of GG in emulsion because of the increased hydrophobic nature and hence reduced water‐binding capacity. The mechanical properties of acrylated GGs were superior compared with GG due to increased compatibility of the additive with the polymer binder. This was further confirmed with increased clarity of the films. Acrylated GG was found to act as a protective additive with reference to UV degradation of the coatings.
Research limitations/implications
The performance of these additives was analysed on un‐pigmented coating formulations, which may not conform with pigmented coatings.
Practical implications
These biodegradable additives synthesised from renewable resources could be used to increase the mechanical strength as UV stabilisers and in some cases also as rheology modifiers.
Originality/value
The use of acrylated polysaccharides to increase mechanical and weathering properties allows the use of biodegradable, renewable resources as opposed to petroleum‐based compounds.
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M.A. Shenoy, A. Sabnis and D.J. D'Melo
To study the effect of addition of free diols and triols in the coating formulation on coating properties.
Abstract
Purpose
To study the effect of addition of free diols and triols in the coating formulation on coating properties.
Design/methodology/approach
Polyester resins were synthesised from maleic anhydride, dimerised fatty acid, neopentyl glycol and tris (2‐hydroxyethyl) isocyanurate (THEIC). Then, ethylene glycol, propylene glycol, glycerol, trimethylol propane and THEIC were added as reactive components to the coating formulation. These coatings were then analysed for various coating properties and compared with those obtained with the base resins.
Findings
The coatings obtained with the addition of these reactive components were found to have improved properties compared with those of the base resins except in cases where the reactive component itself contributed to a reduction in performance, e.g. reduced alkali resistance with the addition of THEIC.
Research limitations/implications
The addition of the free diols and triols required a corresponding increase in the amount of the curing agent to be added.
Practical implications
This process would allow for the tailoring of coatings to suit requirements to a certain extent without modifying the base resin. The addition of low molecular weight components in the coating formulation, which is then incorporated in coatings, could reduce the solvent requirement.
Originality/value
Although polyesters are an established polymeric system in coatings, the use of reactive diluents has not been investigated with the exception of unsaturated polyesters, whose curing chemistry is fundamentally different from that of polyesters focused on in this paper.
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Mazrina Mazlan, Muhammad Rizwan, Ahmad Danial Azzahari, Vidhya Selvanathan, Faridah Sonsudin and Nurshafiza Shahabudin
The purpose of this study is to modify guar gum (GG) into guar gum acetate (GGA) and phthaloyl guar gum (PHGG) by transesterification and phthaloylation, respectively.
Abstract
Purpose
The purpose of this study is to modify guar gum (GG) into guar gum acetate (GGA) and phthaloyl guar gum (PHGG) by transesterification and phthaloylation, respectively.
Design/methodology/approach
GG has been modified into GGA through transesterification reaction between GG and vinyl acetate and PHGG through esterification reaction with phthalic anhydride. The modified GG was characterized by solubility test, Fourier-transform infra-red (FTIR) spectroscopy, proton nuclear magnetic resonance (1H NMR) spectroscopy, X-ray diffractometry (XRD) and thermogravimetric analysis. Swelling properties of GGA and PHGG hydrogels in water were evaluated.
Findings
These two types of modified GG have better solubility such as in dimethyl sulfoxide and N,N-dimethylformamide but no true organosolubility was achieved. The modifications were confirmed through FTIR with new absorption peaks at 1,733 cm−1 for GGA and 1,709 cm−1 for PHGG coupled with observed substitution peaks at 1.80 to 2.20 ppm and 7.40 to 7.90 ppm, respectively, from 1H NMR spectroscopies. XRD revealed both GGA and PHGG are less crystalline than native GG. GGA was found to be more thermally stable than native GG, whereas PHGG was slightly less thermally stable than native GG. The swelling property in distilled water for native GG, PHGG and GGA was 918.43 ± 46.62%, 537.04 ± 2.87% and 393.04 ± 13.42%, respectively.
Research limitations/implications
The GGA and PHGG hydrogels are expected to be useful for biomedical fields such as tissue engineering and drug-delivery.
Originality/value
Modifications of native GG into GGA using vinyl acetate and PHGG using phthalic anhydride are novel.
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Bohao Ma, Jessica Limierta, Chee-Chong Teo and Yiik Diew Wong
The study proposes an evaluation model that allows quantitative characterization of the effects of service quality on consumer’s satisfaction for online food delivery (OFD…
Abstract
Purpose
The study proposes an evaluation model that allows quantitative characterization of the effects of service quality on consumer’s satisfaction for online food delivery (OFD) services in a nonlinear manner. As such, the authors endeavor to bridge the research-to-practice gaps whereby the effect magnitudes and nonlinear patterns of service quality have been overlooked in the current literature.
Design/methodology/approach
The quantitative Kano method is adopted. A Kano questionnaire was first developed by synthesizing and operationalizing existing evidence on OFD service qualities. The questionnaire solicited consumers’ evaluations of 21 OFD service attributes, and it was distributed to an online panel in Singapore. With 580 valid responses, the functions that quantitatively depict effects of each attribute on consumer’s satisfaction were subsequently derived.
Findings
The results reveal that among Singaporean consumers, food quality, reliability of delivery, responsiveness of customer support, ease-of-use of digital interfaces and promotions are pivotal attributes contributing to above-average satisfaction improvement across all performance levels. Meanwhile, delivery riders’ attitudes and real-time tracking functions emerge as substantial contributors to satisfaction at high-performance levels.
Practical implications
The findings provide crucial insights for OFD practitioners in Singapore in resource prioritization and service optimization. This study demonstrated the importance of streamlining customer support services and focusing on the utilitarian aspects of OFD services. Moreover, these results can be employed in advanced service improvement procedures, providing a roadmap for future OFD service enhancements.
Originality/value
This study pioneers the development of a quantitative quality evaluation model in the OFD context. With the established quantitative Kano model, the study addresses the omission of effect magnitudes and nonlinear patterns of service quality. It highlights the transition from a binary “does it affect satisfaction” to a more nuanced “how much does it affect satisfaction” approach, offering a robust understanding of consumer’s satisfaction dynamics.
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Inorganic pigments have been widely investigated due to their chemical stability such as resistance to chemical attacks by acids and alkalis, excellent hardness and high…
Abstract
Purpose
Inorganic pigments have been widely investigated due to their chemical stability such as resistance to chemical attacks by acids and alkalis, excellent hardness and high temperature stability. Cr1.3Fe0.7O3 which is considered as a ceramic nanopigment also seems to be a highly efficient photovoltaic material. The paper aims to discuss these issues.
Design/methodology/approach
In this work, the paper reports the synthesis of a novel and high purity Cr1.3Fe0.7O3 nanopigment via sol-gel process using stearic acid as complexing agent. The method includes formation of an organic precursor with metallic cations homogeneously distributed all over the matrix. Sample characterisations were performed by X-ray diffraction, electron microscopy, UV-vis diffused reflectance spectra and photoluminescence. The transport properties and colour characteristics were also investigated by spectroscopic and technological characterisation of the synthesised nanoparticles.
Findings
The prepared nanopigments were uniform in distribution and a spherical morphology with an average size of about 200 nm was observed. Cr1.3Fe0.7O3 nanoparticles showed a direct band gap value of 2.85 eV and the colour efficiency of the nanopigments evaluated by colourimetric analysis resulted characteristic values of L*=39.96, a*=3.67 and b*=3.12.
Originality/value
This method for synthesis of nanopigments is novel and could be employed for various applications in synthesis of wide variety of nanoceramics.
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Pratima Verma and R.R.K. Sharma
The purpose of this paper is to investigate the linkages among different employee benefits, business strategies and organizational cultures. The manufacturing and service sectors…
Abstract
Purpose
The purpose of this paper is to investigate the linkages among different employee benefits, business strategies and organizational cultures. The manufacturing and service sectors in the conglomerate industry are investigated.
Design/methodology/approach
Analysis of variance (ANOVA) are used for the statistical verification of the hypotheses, whereas Levene’s test and Wilk–Shapiro tests are conducted to verify the assumptions of ANOVA.
Findings
The results reported indicate that the social class benefits (SCB) and long-term benefits (LTB) are high in defenders as compared to prospectors and innovators, whereas group incentive schemes (GIS) are lower in the defender, and power distance and uncertainty avoidance are higher in the defender as compared to prospector and innovator.
Practical implications
This paper highlights that if mismatch among the employee benefits, strategy and culture occurs, then it becomes a hurdle to the good performance of organization and employee. The proposed model focuses on the effective coherence among the strategy, culture and benefits for leveraging the business processes. This research along with enriching the already existing literature would also act as a guidelines to practitioners implementing organizational change and development and to the academicians for extending the research in this area.
Originality/value
It has been established in the study that employee benefits (SCB, LTB, GIS and result-oriented benefits) are completely different for innovators, defenders and prospectors for conglomerate firms.
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Deborah Oyine Aluh, Roland Nnaemeka Okoro and Adamu Zimboh
The purpose of this paper is to assess the prevalence of depression and post-traumatic stress disorder (PTSD) among internally displaced persons (IDPs) in Maiduguri.
Abstract
Purpose
The purpose of this paper is to assess the prevalence of depression and post-traumatic stress disorder (PTSD) among internally displaced persons (IDPs) in Maiduguri.
Design/methodology/approach
The study was a cross-sectional study that took place among the six IDP camps located in Maiduguri metropolis in Borno State. A non-randomized technique was used to sample 1,200 respondents. Face-to-face interviews with selected members of households were carried out confidentially. The study used the Patient Health Questionnaire (PHQ-9) and Impact of Event Scale-6 which were translated to Kanuri. Descriptive and inferential statistics were employed using SPSS version 21.
Findings
The response rate was 100 percent. In total, 96.1 percent (1,153) of the respondents were depressed, while 78 percent (936) of the respondents were symptomatic for PTSD. The prevalence rate of comorbid PTSD with depression was 68.1 percent (817). About one-third of the respondents had moderately severe depression (29.6 percent, n=355) while about one in ten of them were severely depressed (11.3 percent, n=136). The odds of being depressed was 3.308 higher in people aged 51–60 years compared to people between 18 and 20 years. Significant predictors of depression in the sampled population were screening positive for PTSD and being unemployed.
Practical implications
The high prevalence of depression and PTSD among the sampled population calls for structured interventions to deal with mental health problems. The study findings suggest the need for more research (preferably qualitative) on the mental health issues in this population.
Originality/value
This study contributes to the sparse available literature on the mental health of IDPs in Nigeria.
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Marcelo Ribeiro, Rosana Frajzinger, Luciane Ogata Perrenoud and Benedikt Fischer
Brazil’s street-based drug use is mostly characterized by non-injection psychostimulant (e.g. crack-cocaine) drug use in Brazil, with limited interventions and service…
Abstract
Purpose
Brazil’s street-based drug use is mostly characterized by non-injection psychostimulant (e.g. crack-cocaine) drug use in Brazil, with limited interventions and service availability. Recently, an influx of multi-ethnic migrants within an urban drug scene in Sao Paulo was associated with heroin use, a drug normatively absent from Brazil. The purpose of this paper is to characterize and compare heroin use-related characteristics and outcomes for an attending sub-sample of clients from a large community-based treatment centre (“CRATOD”) serving Sao Paulo’s local urban drug scene.
Design/methodology/approach
All non-Brazilian patients (n = 109) receiving services at CRATOD for 2013–2016 were identified from patient files, divided into heroin users (n = 40) and non-heroin users (n = 69). Based on chart reviews, select socio-demographic, drug use and health status (including blood-borne-virus and other infections per rapid test methods) were examined and bi-variately compared. Multi-variate analyses examined factors independently associated with heroin use.
Findings
Most participants were male and middle-aged, poly-drug users and socio-economically marginalized. While heroin users primarily originated from Africa, they reported significantly more criminal histories, drug (e.g. injection) and sex-risk behaviors and elevated rates of BBV (e.g. Hepatitis C Virus and HIV). A minority of heroin users attending the clinic was provided methadone treatment, mostly for detoxification.
Originality/value
This study documented information on a distinct sample of mostly migration-based heroin users in Sao Paulo, Brazil. Based on the local experience, global migration dynamics can bring changes to established drug use cultures and services, including new challenges for drug use-related related behaviors and therapeutic interventions that require effective understanding and addressing.
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Gustavo Santos, Célia Soares, Raquel Rebelo and Paula Ferreira
While awaiting resolution of their legal process, undocumented migrants (UM) face several challenges, including limited access to public health care. The purpose of this paper is…
Abstract
Purpose
While awaiting resolution of their legal process, undocumented migrants (UM) face several challenges, including limited access to public health care. The purpose of this paper is to survey UM attending a detention centre in Oporto (Portugal) to estimate the prevalence of mental health disorders in this population.
Design/methodology/approach
A retrospective chart review was performed with the relevant sociodemographic and clinical data of all UM in the process of coercive removal from Portuguese territory, observed by Doctors of the World, during three years (2014–2016). The Tenth Version of International Classification of Mental and Behavioural Disorders was used for nosological classification.
Findings
In total, 393 detainees were eligible for the study. Most detainees were male (84 per cent) and 76 months was the mean length of stay in Portugal before detention. In total, 29 per cent of detainees were diagnosed with a mental and behavioural disorder. The most prevalent diagnosis was neurotic, stress-related and somatoform disorders (47 per cent). UM with dual diagnosis (28 per cent) led to the articulation with the integrated centres of drug addiction, which provided and monitored opioid substitution therapy. Female UM were more prone to develop any mental and behavioural disorder when compared to men (χ2=7,017; p<0.05).
Research limitations/implications
In total, 9 per cent of the detainees were excluded from this study due to incomplete data on their medical charts. Some detainees presented oppositional behaviour, hostility towards others and refused to be assessed by the medical team. Both situations could have biased the prevalence of mental disorders. Finally, the appropriateness of the western model of mental health disorders (ICD-10) in the study population is controversial, considering the culture-bound phenomenology and syndromes.
Originality/value
This paper identified the most prevalent mental health disorders in UM detained in Portugal. The most prevalent mental health disorders were either stress-related (associated with the detention itself) or related to previous patterns of substance abuse. Given the study outcomes, it is highly recommended to mobilise human and technical resources to provide specialized mental health care to UM at least while detention policies could not be changed.