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In this work, we study the rheology of suspensions of polystyrene (PS) spheres at concentrations ranging from 8 to 66% (v/v) in a matrix of molten ethylene vinyl acetate copolymer (EVA) at temperatures spanning through the glass transition temperature of the PS spheres. As a result of the significant difference between the softening temperatures of these blend components, the melt order plays a crucial role in the generation of the blend morphology, rheology, and optimization of processing conditions. When the PS is rigid (below T g ), the suspensions showed significant Mullins and Payne effects, disappearing at higher temperatures where PS was sufficiently softened. The origin of these effects is postulated to be due to the extensive filler-filler contacts and radial alignment of the PS beads. Near the glass transition of PS, the PS spheres became deformable and viscosity of the suspension showed an unusual variation as a function of PS loading. The Krieger-Dougherty model was used to predict viscosity variation with volume fraction. We demonstrate that the deformability of the "solid" PS spheres significantly affects the reduced suspension viscosity at both intermediate volume fractions of 0.42 to 0.44, where there was an anomalous dip in viscosity, and at higher volume fractions beyond 0.60, where the increase in viscosity was not as prounounced as that for suspensions of rigid particles. [ABSTRACT FROM AUTHOR]

The starting point for the preparation of polymeric membranes by phase inversion is having a thermodynamically stable solution. Ternary diagrams for the polymer, solvent, and non-solvent can predict this stability by identifying the phase separation and describing the thermodynamic behavior of the membrane formation process. Given the lack of data for the ternary system water (H2O)/hydrochloric acid (HCℓ)/polyamide 66 (PA66), this work employed the Flory–Huggins theory for the construction of the ternary diagrams (H2O/HCℓ/PA66 and H2O/formic acid (FA)/PA66) by comparing the experimental data with theoretical predictions. Pure polymer and the membranes produced by phase inversion were characterized to provide the information required to create the ternary diagrams. PA66/FA and PA66/HCℓ solutions were also evaluated regarding their classification as true solutions, and the universal quasi-chemical functional group activity coefficient (UNIFAC) method was used for determining non-solvent/solvent interaction parameters (g12). Swelling measurements determined the polymer/non-solvent interaction parameter (χ13) for H2O/PA66 and the solvent/polymer interaction parameter (χ23) for PA66/FA and PA66/HCℓ. The theoretical cloud point curve was calculated based on “Boom’s LCP Correlation” and compared to the curve of the experimental cloud point. The ternary Gibbs free energy of mixing and χ23 indicated FA as the best solvent for the PA66. However, for HCℓ, the lower concentration (37–38%), volatility, and fraction volume of dissolved PA66 (ϕ3) indicated that HCℓ is also adequate for PA66 solubilization based on the similar membrane morphology observed when compared to the PA66/FA membrane.

Low-fat mayonnaise has gained widespread popularity as a condiment, driven in part by the global rise in obesity rates, which is partially linked to excessive fat consumption. In this study, the bigel systems were designed by preparing fish oil oleogels and gelatin hydrogels to produce low-fat mayonnaise. As the oleogel content increased in bigels, a phase inversion shifted from oil-in-water (O/W) systems to water-in-oil (W/O) systems. Rheology and mechanical property analysis revealed that the hardness and gel strength of bigels improved as the oleogel content increased. The freeze-thaw stability of bigels was impacted by the ratio of oil and water phases, with O/W systems enduring one additional freeze-thaw cycle compared to W/O systems. The bigel containing 40% oleogel (BG 40) and lemon essential oil significantly enhanced antioxidant properties, as measured by the levels of primary and secondary oxidation products. The antioxidative capacity of the gel, as indicated by the reduced development of primary and secondary oxidation products, was 301.4% and 196.7% greater, respectively, compared to that of the pure oleogel. Based on magnetic resonance imaging and sensory rating analysis, sample BG 40 demonstrated the most homogeneous structure and the best sensory properties. The sample BG 40, used as the fat substitute in preparing low-fat mayonnaise, reduced total oil content compared to full-fat mayonnaise. Our findings contributed to the development of low-fat mayonnaise using fish oil-based bigels, which exhibit exceptional sensory and antioxidant properties. [Display omitted] • Bigel systems with fish oil oleogels and gelatin hydrogels were prepared. • The bigels exhibited outstanding mechanical and rheological properties. • The O/W bigel with LEO had outstanding sensory and antioxidant properties. • The low-fat mayonnaise was employed as a substitute for less healthy fats. [ABSTRACT FROM AUTHOR]

This study focuses on the development of an efficient membrane-based clarification process to enhance the performance of subsequent ultrafiltration and produce high-quality sweet lime juice. A range of casting solutions were prepared using a blend of pore-forming polymers, including polyvinylpyrrolidone (PVP), polyvinylidene fluoride (PVDF), and cellulose acetate (CA), dissolved in dimethylformamide (DMF) solvent through the phase inversion technique. To further enhance the membrane's performance, four biopolymers poly (lactic acid) (PLA), xanthan gum, chitosan, and gelatin were incorporated, with and without clay, to refine its structure, porosity, and surface properties. The resulting membranes were characterized by FT-IR, SEM, and AFM, and their flux behaviour and fouling profiles were evaluated. The quality of the clarified juice was assessed by measuring total suspended solids (TSS), clarity, color, and apparent alcohol insoluble solids (AIS). Despite a reduction in permeate flux, the Xanthan-clay-loaded membrane enhanced juice quality and clarity. For the PLA-based membrane and the xanthan-based membrane, the fouling coefficient was lower. This membrane-based clarification technique can be applied effectively in the juice processing industries to improve product quality., Competing Interests: Declaration of competing interest KARTHIKUMAR SANKAR reports equipment, drugs, or supplies, statistical analysis, and writing assistance were provided by Kamaraj College of Engineering and Technology. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025. Published by Elsevier B.V.)