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This study focuses on the effect of ionic liquids (ILs) on the cure characteristics and filler dispersion of natural rubber (NR) and styrene-butadiene rubber (SBR) gum and filled compounds. The complexation of ionic liquid with zinc oxide (ZnO) increases the activity of ZnO and the cure rate together with improved filler dispersion. This has also increased the rubber filler interaction. Imidazolium and chloride based ionic liquids with different cationic groups were compared and characterized by thermogravimetric analysis, Fourier transform infrared spectroscopy, and differential scanning calorimetry to understand the thermal and chemical behavior of the compounds. Interestingly, it was found that the ionic liquid can act as an activator and is able to accelerate the vulcanization rate with improved rubber filler interaction. The complexes formed by IL-Zn were shown to be much more reactive than Zn-stearic acid complexes. The dispersion of carbon black in the NR and SBR compounds was studied by using Field Emission Scanning Electron Microscope and Transmission Electron Microscope and the results demonstrate that ILs could significantly improve the filler dispersion. Thus, this study has revealed the multifunctional role of ionic liquids in rubber compounds. Highlights * This article describes the dual role of the ionic liquid (IL) in rubber compounds. * It can act both as an accelerator-activator as well as an efficient dispersing aid. * The complexation of IL with zinc oxide (ZnO) plays a crucial role in enhancing the activity of ZnO. * As a result, the physico-mechanical properties of both natural rubber and styrene-butadiene rubber based compounds are significantly improved. KEYWORDS accelerator activator, cure characteristics, electron microscope, ionic liquid, 1 | INTRODUCTION Curing is an important process in the manufacturing of rubber products, as it involves the creation of cross-links, thereby hardens the rubber and boosts its strength and [...]

Abstract Background Multi-morbidity is a pervasive and growing issue worldwide. The prevalence of multi-morbidity varies across different populations and settings, but it is particularly common among older adults. It poses substantial physical, psychological, and socio-economic burdens on individuals, caregivers and healthcare systems. In this context, the present study aims to provide an insight on the prevalence and degree of multi-morbidity; and also, on the relationship between level of multi-morbidity and morbid conditions among a group of slum-dwelling older women. Methods This community based cross-sectional study was conducted in the slum areas of urban Kolkata, West Bengal, India. It includes total 500 older women, aged 60 years or above. Pre-tested schedules on so-demographic and morbidity profile have canvassed to obtain the information by door-to-door survey. To determine the relationship between the level of multi-morbidity and morbid conditions, correspondence analysis has performed. Results The study revealed three most prevalent morbid conditions- back and/or joint pain, dental caries/cavity and hypertension. The overall prevalence of multi-morbidity was 95.8% in this group of older women. It was highly over-represented by the oldest-old age group (80 years and above). Majority were found to suffer from five simultaneous morbid conditions that accounted for 15.2% of the total respondents. All of the oldest-old women of this study reported to suffer from more than two medical conditions simultaneously. Three distinct groups were formed based on the inter-relationship between level of multi-morbidity and morbid conditions. The group 1 and 2 represents only 27.8% and 18% of the total sample. Whereas, group 3 comprises the highest level of morbidities (≥ 6) and 52.8% of total sample, and strongly related with general debilities, cardiac problems, asthma/COPD, gastrointestinal, musculoskeletal problems, neurological disorders, hypothyroidism and oral health issues. Conclusion The findings confirmed the assertion that multi-morbidity in slum living older adults is a problem with high prevalence and complexity. This study proposes an easily replicable approach of understanding complex interaction of morbidities that can help further in identifying the healthcare needs of older adults to provide them with healthy and more productive life expectancy.