Tailoring highly stretchable, ultra-barrier, and transparent gelatin/PVA emulgel-templated oleofilms: Effect of oil saturation degree

Fully-substituted cellulose esters with acyl substituents ranging in size from C2 to C18 were synthesized using the acyl chloride method. Films were prepared from the purified esters by either solvent-casting or compression-molding at elevated temperatures. Oxygen and water vapor permeability was determined under different conditions of pressure and moisture. The relationship between cellulose ester structure and barrier properties was examined. The results revealed linear relationships between water vapor and oxygen permeabilities and molar ester substituent volume as well as several structural factors relating to polymer polarity and hydrophobicity, such as aliphatic (methylene) content, solubility parameter, and contact angle. Films from long chain cellulose esters (LCCE) with acyl substituents in the size range between C8 and C18 were found to represent effective barriers to water vapor transport while their obstruction to the transfer of oxygen remained low. It was concluded that the hydrophobic nature of LCCEs is responsible for the control of water vapor transport, and that spatial factors dominate the transfer of oxygen.

Monolaurin is known as a monoglyceride of lauric acid, which act as an emulsifier and antimicrobial. One potential of monolaurin raw materials is palm kernel oil (PKO), which can be fractionated into palm kernel olein (PKOo) and palm kernel stearin (PKS). This study aims to determine the enzymatic glycerolysis influence of PKOo and PKS mixture in different ratios and time, on monoacylglycerol (MAG), diacylglycerol (DAG), and triacylglycerol (TAG) profiles. The Glycerolysis process of PKOo-PKS fat blends were carried out in different ratios of (60:40, 40:60, and 20:80 w/w) using commercial lipases (Lypozime RM IM) at 50°C, with an oil:glycerol molar ratio of 1:4, in a tert-butanol solvent system, between 3 to 24 hours. The results showed that the glycerolysis of PKOo and PKS in different ratios yielded varying product reactions with similar compositions (1.8-3.9% MAG, 73.2-76.4% DAG, and 20.7-24.2% TAG). A higher and not significant MAG was observed during the period of 24 hours. Also, the monolaurin was obtained at the ratio of 40:60 PKOo:PKS, within the glycerolysis time of 3 to 24 hours, at approximately 2.18±0.59% and 3.47±0.62%, respectively. The FTIR analysis also showed that the monolaurin sample was identical to the standard type, with the formation of OH group at wave number and cluster C=O ester of 3368.64 cm-1 and 1734.03 cm-1, respectively.

Chemical interesterification (CIE) is one of the important technological processes for the production of zero-trans fats. The aim of this study was to produce trans-free cocoa butter alternatives (CBAs) from palm kernel stearin (PKS), coconut oil (CNO) and fully-hydrogenated palm stearin (FHPS) blends via CIE using sodium methoxide as a catalyst. The physicochemical properties, crystallization and melting behavior, solid fat content (SFC), crystal morphology and polymorphism of the structured lipids (SLs) obtained and the corresponding physical blends (PBs) were characterized and compared with commercial CBAs. After CIE, randomization of fatty acid distribution within and among triacylglycerol (TAG) molecules of PKS, CNO and FHPS resulted in a modification in TAG compositions of the PKS/CNO/FHPS blends and improved the properties and crystallization behavior of the blends. SFC and slip melting points of all SLs decreased from those of their respective PBs. In particular, SLs obtained from CIE of blends with 60-70% wt. PKS (blend ratios 60:10:30 and 70:10:20) exhibited the melting characteristic, SFC curves, crystal morphology and polymorphic form most similar to the commercial CBAs. In addition, these blends melted almost completely at body temperature, an improvement from that of the commercial CBAs. SLs obtained from CIE of blends with 60-70% wt. PKS has high potential to be used commercially as trans-free CBAs for the confectionery industry. © 2021 Society of Chemical Industry.

Concrete can be susceptible to damage when it is exposed to freezing and thawing (FT). It has been shown that the potential for damage depends on the degree of saturation (DOS). When concrete has a low DOS, it does not show damage during an FT cycle. However, when the DOS exceeds a specific value (critical DOS), the concrete shows damage resulting from the FT cycle. The objective of this article is to measure the length change for cementitious specimens with varying DOS. It is hypothesized that these length change measurements can be used to quantify the critical DOS (DOSCR) for cementitious paste specimens exposed to FT. Specimens with a low DOS show a nearly linear length change response throughout the entire range of temperatures tested. Specimens with a high DOS (i.e., DOS > DOSCR) show a notable change in length at temperatures associated with the freezing and thawing points of water. The strain reduction associated with the melting of ice is calculated by normalizing the length reduction during the melting of ice with the initial length of the specimen. A DOSCR can be obtained by fitting a line between the strain reduction and the DOS. Another parameter known as residual strain can be used to quantify damage. Residual strain is defined as strain that exists in the specimen after an FT cycle. Only specimens with a high DOS (DOS > DOSCR) show residual strain. The approach presented in this paper provides an alternative method that can complement other existing tests to determine the DOSCR for use in the sorption-based model.

Investigating the optimum unsaturated fatty acid content and oil length for auto-oxidative drying of palm-stearin-based alkyd resin

Effects of soft segment content, hydrophilicity of polyether macroglycol soft segment and presence of polydimethylsiloxane co-soft segment on oxygen and water vapor permeabilities of polyetherurethanes were investigated. Polyetherurethanes were synthesized using a bulk synthesis procedure and solution cast as thin films. Oxygen and water vapor transport measurements were performed at 38 °C, 100% relative humidity (RH) and 4 mm Hg oxygen gradient, and 40 °C and 80% RH test gradient, respectively. The soft segment content and structure had profound influences on oxygen and water vapor permeabilities of the polyetherurethanes. Water vapor and oxygen permeabilities of polyetherurethanes increased with increasing soft segment content. Polytetramethylene oxide based polyetherurethanes (PTMO-PEU) had high oxygen permeabilities and polyethylene oxide based polyetherurethanes (PEO-PEU) had high water vapor permeabilities. Addition of silicone co-soft segment increased water vapor permeability and slightly reduced oxygen permeability of PTMO-PEU. Its effect on PEO-PEU was the reverse of that of the PTMO-PEU systems.

Electrospun synthetic fiber was used to reinforce protein-based composite. Two monolayer and laminated films based on either made from just isolated oat protein or a composite containing an interlayer of nylon-6 nanofiber was developed. It was revealed that monolayer film has relatively weak barrier and mechanical properties compared to other proteinous films. To improve film characteristics, 0.5, 1, and 1.5% (wt/wt) of the nanofiber were incorporated into the film. According to the results, film solubility in water decreased while its oxygen and water vapor permeability and mechanical properties were significantly improved. Due to the presence of 1.5% (wt/wt) of nanofiber, the elastic modulus increased significantly and, therefore, glass transition temperature (TG) of laminated film was also increased. Addition of nanofibers did not significantly affect optical properties. The results show that incorporation of electrospun nylon nanofibers into a film obtained from a natural polymer may show promise and improves its properties. Practical applications Laminating of different films and combination of their features are one of the popular methods to improve properties of biodegradable films. In this study, electrospun nylon nanofiber was incorporated as interlayer of film based on oat protein. By this way, effect of interlayer nylon nanofiber mat (NNM) on physical and mechanical properties of oat protein–NNM was investigated. The results showed that water vapor and oxygen permeability, mechanical properties, and its resistance to soluble in water improved, while interlayer did not have significant effect on optical properties of laminated film.

The shear strength of soil-structure interfaces is relevant to the stability of energy piles. The thermo-hydro-mechanical processes can have a strong effect on the behaviour of interfaces between unsaturated soils and piles. Temperature changes lead to water movement in the soil. The moisture loss or gain in the soil causes drying or wetting. In addition, water movement influences the heat transfer properties of the soil. Temperature and moisture content changes affect the magnitude of soil suction in unsaturated soils. Changes in soil suction alter the strength and deformation characteristics of the soil mass and soil-structure interfaces. Similar to the effects of temperature changes, the mechanical loading and the changes in hydraulic conditions in the ground would cause changes in the void ratio, degree of saturation, suction, strength and deformation characteristics of soil. The interface behaviour under varying thermo-hydro-mechanical (THM) conditions is classified as a coupled problem and this is the subject of the present research. In the present investigation, laboratory studies and numerical analyses are carried out to evaluate the THM effect on the behaviour of interfaces between an energy pile material and an unsaturated soil. A 3D interface apparatus (Fakharian and Evgin 1996) has been modified (Fu et al. 2013) to allow the behaviour of an interface to be studied under thermo-mechanical loading conditions. In the present study, the experiments are conducted on soil samples with low degree of saturation and high degree of saturation. It is found that in interface tests using soil samples with low degree of saturation, the adhesion increased due to a positive effect of suction on strength than the negative effect of increasing temperatures. However, in interface tests on soil samples with high degree of saturation, the adhesion decreased with increasing temperatures while the positive effect of suction was not large enough to overcome the negative effect of increasing temperatures. This is a new finding that has not been reported anywhere in the literature. The friction angle for both soil samples (with different degrees of saturation) changed slightly with temperature change. Coupled finite element analyses conducted in the present study provide the following geotechnical information that would be useful for the design of energy piles: (a) Bearing capacity of the pile with and without the effect of temperature, (b) The effect of degree of saturation (or suction) on the strength and deformation characteristics of both the soil and the soil-structure interface, (c) Temperature effects on the amount of pile head movements (up or down), (d) Temperature induced stresses in the pile, (f) Amount of heat that can be stored or extracted from the ground as a function of time. At the initial stages of this study, THM effects on the behaviour of energy piles under saturated and unsaturated conditions are analyzed by using SIGMA/W and VADOSE/W finite element codes of GeoStudio 2012. Although these codes are not multi-physics FE codes, it is possible to use them sequentially to obtain results that will show the trends in pile behaviour. This numerical approach is used first to analyze the behaviour of an energy pile installed partially in unsaturated soil. The moisture content and temperature distributions around a 10 m long, bored pile are calculated using transient analyses. Changes taking place in the stress state along the pile shaft and the bearing capacity of the pile at different temperatures are calculated. In the second part of the numerical analysis of the present study, THM effects on the behaviour of energy piles under saturated and unsaturated conditions are analyzed by using PLAXIS 2D finite element code. PLAXIS is a fully couples finite element code. In order to enhance present understanding of the behaviour of energy piles and do the analysis correctly, a fully coupled analysis involving thermo-hydro-mechanical processes was carried out. Three simulations (mechanical loading only, thermo-mechanical coupling and thermo-hydro-mechanical coupling) are conducted using case studies that are available in the literature. In addition, the behaviour of a generic energy pile, which is installed in a kaolin-sand mixture, is studied by taking into consideration of thermo–hydro-mechanical processes. The coupled analysis provided the distributions of temperature, degree of saturation, suction and heat flux in the analysis domain. Numerical results of the fully-coupled method are compared with the results of sequential method of analysis.

In view of the nutritional disadvantages of partial hydrogenation (production of unhealthy trans fats) interesterification (IE) has emerged to produce suitable fats for trans‐free formulations that have improved physicochemical properties. In this context, both chemical (CIE) and enzymatic (EIE) interesterification techniques can be used. However, it has been found that CIE technology may produce process‐related by‐products known as dialkyl‐ketones (DAK). The current study aims at investigating the formation of DAK during IE. Therefore, five edible oils and fats were selected based on their potential use in IE: Elaeis Guineensis palm stearin (POSt), high oleic palm stearin (HOPSt), palm kernel stearin (PKSt), high oleic sunflower oil (HOSO) and high oleic palm oil (HOPO). The investigated blends were divided into HOPO‐based blends (POSt:HOPO 50:50, PKSt:HOPO 50:50, HOPSt:HOPO 50:50 and 30:70 wt:wt%) and HOSO‐based blends (POSt:HOSO 30:70, 50:50 and 70:30 wt:wt%). They were all subjected to both CIE (using sodium methoxide) and EIE (using TLIM lipase as catalyst); analyses of physical properties and determination of DAK content were performed before and after IE. This study demonstrates that DAK were not formed during the EIE process regardless of the investigated matrix, whereas they were produced during CIE, and that they require sufficient rearrangement of triglycerides (TAG) to be formed. It has also been shown that unsaturated fatty acids are more prone to form DAK regardless of the fat matrix. However, there is no linear relationship between the amount of DAK and the amount of unsaturated fat in the matrix.

Purpose: To use differential scanning calorimetry (DSC) to predict the liquefaction time and dissolution profile of some commercial paracetamol suppositories as well as paracetamol suppositories formulated with palm oil base.Methods: The suppository base was prepared by mixing hydrogenated palm oil and palm kernel stearin in a ratio of 8:2. Three commercial paracetamol suppositories (A, B, and C) were purchased, while product D, paracetamol suppository was formulated with suppository base using the double casting method. In-vitro drug release from suppositories was determined using DSC and the effect of liquefaction on drug release was studied. The relationship between suppository melting and dissolutionwas analysed statistically.Results: The melting temperature of products A and B were 41.0 and 40.0 ºC respectively, whereas those of products C and D were 35.9 and 33.1 ºC, respectively. The liquefaction time of the suppositories were 61.4 (A), 54.2 (B), 9.0 (C) and 7.4 min (D). Less than 40 % paracetamol was released from products A and B in 2 h, while products C and D showed good dissolution with > 95 % drug release in 15 min. Statistical analysis using Pearson’s test indicates that the proportion of melt in the suppository base correlates well with drug release (p < 0.05).Conclusion: Paracetamol release from palm oil suppositories is rapid and correlates with melting of the base. DSC can be used to predict drug release in paracetamol suppository formulations.Keywords: Palm oil, Liquefaction time, Paracetamol, Suppositories, Thermal analysis.

The aims of this study were to assess sulfate adsorption in Japanese forest soils and to find and evaluate traces of past heavy anthropogenic sulfur deposition based on the degree of saturation as calculated based on the theoretical adsorption capacity determined by isotherm experiments and the amount of actual adsorbed sulfate. Investigations were conducted at two forest sites, a site in Yokkaichi that is exposed to serious air pollution containing sulfur compounds and a site in Inabu that is unpolluted. The distribution of phosphate-extractable sulfate concentration did not differ between the Yokkaichi site (1.11–13.2 mmol kg−1) and the Inabu site (0.40–11.0 mmol kg−1), and the values were higher than published data for North America and Europe. In contrast, the degree of sulfate saturation in soils of the Yokkaichi site was higher than that in soils of the Inabu site. These results indicate that the degree of sulfate saturation is valuable information for the evaluation of sulfur deposition history. The higher degree of saturation at Yokkaichi site may be due to enhanced sulfate adsorption by soils resulting from substantial past sulfur deposition.

This study investigates the incorporation of nano‐silver carbon black (AgCB) into polypropylene (PP) to develop nanocomposites with enhanced mechanical, thermal, barrier, and antibacterial properties. AgCB, synthesized with a carbon black‐to‐silver ratio of 19:1, was incorporated into PP at 0.5–5 wt% via melt blending. At 1 wt%, AgCB improved tensile strength by 21.5%, enhanced thermal stability, and reduced water vapor and oxygen permeability, achieving optimal performance with uniform dispersion. With increasing AgCB content, antibacterial activity improved significantly, achieving a sterilization rate exceeding 99.7%, although higher concentrations led to agglomeration, reducing mechanical and barrier performance. The dual function of AgCB as a nucleating agent and functional additive was demonstrated through DSC, WAXRD, and antibacterial tests. This work highlights the potential of AgCB as a cost‐effective filler for PP composites, suitable for applications requiring enhanced durability, barrier properties, and antimicrobial efficacy. Highlights Nano‐silver carbon black improves PP crystallinity and barrier performance. Optimal 1 wt% AgCB enhances PP's tensile strength and thermal stability. AgCB creates tortuous pathways, reducing water vapor and oxygen permeability. Low‐cost AgCB (CB:Ag = 19:1) achieves strong antibacterial activity (>99% efficacy). AgCB mitigates nanoparticle agglomeration, enhancing filler dispersion in PP.

The effects of three bilayerforming methods (liquid protein spread on dry film, heat pressing dry films, and solventlaminating dry films) on physical and barrier properties were investigated. These bilayer films were generated using soyprotein isolate, wheat gluten protein, and corn zein protein. Bilayer films were evaluated for enhanced properties (tensilestrength, percent elongation, water vapor, and oxygen permeability) over single layer films. Using Xray crystallography,these films showed no changes in degree of crystallinity. Depending upon film type in this study, protein bilayer films exhibitedreduced, similar, and enhanced properties. Hydration properties, solvent and protein interactions, film thickness, surfaceproperties, or heat and pH differences influenced the formation of these films. Water vapor permeability for these films rangedfrom 1.3
10
9 g m 1 s 1 Pa 1 for soy sprayed on corn film to 3.5
10
9 g m 1 s 1 Pa 1 for solvent laminating wheat and soyfilms. Oxygen permeability ranged from 2.67
10 17 moles m m 2 s 1 Pa 1 for spraying soy on corn films to 8.81
10 19 molesm m 2 s 1 Pa 1 for pouring soy on wheat film. Tensile strength ranged from 1.57 MPa for spraying corn on wheat films to9.10 MPa for heat pressing wheat and corn films. Elongation ranged from 5.36% for pouring soy on corn films to 204.12%for pouring soy on wheat films. Bilayer films appear to exhibit reduced tensile strength, similar oxygen permeability,enhanced percent elongation, and greatly increased water vapor permeability.

Cold water fish gelatin films: Effects of cross-linking on thermal, mechanical, barrier, and biodegradation properties

Starch-based films offer the advantages of biodegradability, edibility, barrier properties, flexibility, and adaptability. This study compared the physicochemical properties of starch-based films by adding raw fish collagen and hydroxypropylmethylcellulose (HPMC). The tensile properties were evaluated, and the interaction with water was analyzed. Barrier properties, such as water vapor and oxygen permeability, were examined, and optical properties, such as gloss and good internal transmittance, were evaluated. The films were evaluated as coatings on Andean blackberries (Rubus glaucus Benth) for 2 weeks at 85% RH and 25°C. The results showed that the inclusion of collagen caused a reduction in the tensile strength and elastic modulus of the films. Also, the formulation with the highest collagen concentration (F7) exhibited the lowest weight loss and water vapor permeability, also it had the highest collagen concentration and showed the highest reduction in Xw and WAC, with values of 0.048 and 0.65 g water/g dry film, respectively. According to analyzing the optical properties, F1 presented the highest bright-ness and transmittance values, with 18GU and 82 nm values, respectively. In general, the films and coatings are alternatives to traditional packaging materials to prolong the shelf life of these fruits.