Tomasz Wasilewski

Influence of Critical Micelle Concentration (CMC) on Tribological Properties of Aqueous Solutions of Alkyl Polyglucosides

Here, the results of studies on the use of water-alkyl polyglucosides (APGs) compositions as lubricants carried out with steel ball-polyamide disc apparatus are presented. The range of values of CMC in aqueous solutions of two different mixtures of APG was determined on the basis of physicochemical properties. The results obtained showed that aqueous solutions of APGs were effective lubricants lowering the friction coefficient and wear. Increase in activity of APGs was observed above CMC in bulk phase. This was in compliance with our earlier results that, above CMC, the formation of the adsorption layer on the interface led to significant lowering of the friction coefficient and increase in the ability of friction nodes to transfer a load.

Tribological and physical‐chemical properties of aqueous solutions of cationic surfactants

Purpose – Modern cutting fluids often are real aqueous solutions of chemical compounds. That form of cutting fluid is simpler in preparation, as compared to emulsions and microemulsions. The water base is a good cooling medium of high‐ecological value. The purpose of this paper is to discover water‐soluble additives that could improve the lubricity of water.Design/methodology/approach – Three cationic surfactants were chosen to be analyzed. Their tribological properties were verified using two testers: T0‐2 (four‐ball machine) and T‐11 (ball‐on‐disk). The results of the tests performed using friction couples made of steel (T0‐2, T‐11) and steel‐ceramics (T‐11) were satisfactory.Findings – The friction coefficients and wear scar diameters are even a few times smaller, as compared to the ones measured in a water environment.Originality/value – The paper demonstrates that the crucial role in improvement of the tribological properties is played by the surface activity of the additives (confirmed by the measur...

Role of macromolecules in the safety of use of body wash cosmetics.

One of the most challenging problems related to the use of surfactants in body wash cosmetics is their potential to cause skin irritations. Surfactants can bind with proteins, remove lipids from the epidermal surface, contribute to the disorganization of liquid crystal structures in the intercellular lipids, and interact with living skin cells. These processes can lead to skin irritations and allergic reactions, and impair the epidermal barrier function. The present study is an attempt to assess the effect of polymers and hydrolysed proteins present in the formulations of model body wash cosmetics on product properties. Special attention was given to the safety of use of this product type. The study examined three macromolecules: polyvinylpyrrolidone (PVP), hydrolysed wheat protein (HWP) and polyvinylpyrrolidone/hydrolysed wheat protein crosspolymer (PVP/HWP). The addition of the substances under study was found to improve the foaming properties of body wash cosmetics, increase their stability during storage, and contribute significantly to an improvement in the safety of product use by reducing the irritant potential. The strongest ability to reduce the skin irritation potential was determined for the formula enriched with the PVP/HWP crosspolymer.

Alkyl Polyglucosides as Components of Water Based Lubricants

Water can be used as an ecological lubricant base if it is possible to select additives which can beneficially modify its tribological and corrosion properties. Additionally, those additives should not be harmful to human health and the natural environment. These conditions limit or even eliminate the possibility for the application of the additives used in traditional oil bases as they are insoluble in water and often toxic. Alkyl polyglucosides (APGs) have been suggested as additives improving lubricating properties of water. They are biodegradable and do not have to be recycled. They exhibit surface activity. They produce micelles at low concentration and lyotropic liquid crystals at high concentration. Two types of alkyl polyglucosides differing in alkyl chain lengths and degrees of polymerization were used in this investigation. Tribological tests were carried out using a ball-on-disc T-11 tester. The balls were made of steel, whereas the discs were made of steel, aluminium oxide, zirconium oxide, polyamide and poly(methyl methacrylate). The description of the device and the methods has been given in the literature (Szczerek and Tuszyński in TriboTest 8:273–284, 2002). The addition of APGs improves the lubricating properties of water. The relative decrease in motion resistance and wear depends both on the type of friction couple and on the kind of alkyl polyglucoside used. The tribological test results obtained were correlated with the activity of APGs measured as wettability of friction couples by their solutions.

Supercritical carbon dioxide blackcurrant seed extract as an anti-irritant additive for hand dishwashing liquids

ABSTRACT The study investigated the effect of hydrophobic, blackcurrant seed extract (Ribes nigrum L.) obtained under supercritical CO2 conditions on the anti-irritant properties of hand dishwashing liquids. A range of liquids differing in extract concentration (0–0.5 wt%) were prepared. The product prototypes were subjected to tests focusing on their anti-irritating property and functionality. Based on the zein values and measurements of changes in the pH level of the bovine albumin solution, the liquids were shown to be markedly safer to use. It was noted that an increase in extract concentration in a product leads to a deterioration of detergent and foaming properties. The highest concentration of the extract allowing the achievement of acceptable results was 0.3 wt%. The results suggest that hydrophobic plant extract, for example, from blackcurrant seed can be an interesting raw material for reducing the irritating potential of liquid agents designed for hand dishwashing. GRAPHICAL ABSTRACT

Hydrophilic Dogwood Extracts as Materials for Reducing the Skin Irritation Potential of Body Wash Cosmetics

A significant problem related to the use of surfactants in body wash cosmetics is their propensity to trigger skin irritations. Only scarce literature exists on the effect of plant extracts on the skin irritation potential. The present study is an attempt to determine the effect of hydrophilic dogwood extracts on the irritant potential of body wash gels. Extractants used in the study were water and mixtures of water with glycerine, water with trimethylglycine (betaine), and water with plant-derived glycol (propanediol). The basic biochemical properties, i.e., the ability to neutralize free radicals, and the content of polyphenols, anthocyanins and flavonoids, were determined. An attempt was undertaken to analyze the impact of the extract added to natural body wash gel formulations on product properties. The skin irritation potential was assessed by determining the zein number and the increase in the pH level of the bovine serum albumin (BSA) solution. The viscosity and foaming ability of the resulting products were evaluated. The studies revealed that an addition of dogwood extract contributes to an improvement in the properties of body wash gels and significantly increases the safety of product use through reducing the skin irritation effect.

Effect of Molecular Weight of Polymers on the Properties of Delicate Facial Foams

Abstract Body wash cosmetics are among the most popular and numerous groups of cosmetic products. In chemical terms, they are solutions of surface active agents with the addition of multiple substances such as preservatives, moisturizing agents, fragrances or viscosity modifiers, the aim of which is to improve specific product properties. The present study evaluated the effect of the molecular weight of polyvinylpyrrolidone (PVP) on the properties of face washing products in the form of foam produced with foaming dispensers. A special focus was on key product quality characteristics including foaming properties and skin irritation potential. An addition of PVP to the formulation was found to contribute to an improvement in product foaming properties and a decrease in skin irritation potential. In addition, the studied properties of samples were shown to improve in proportion to the increasing molecular weight of the polymer.

Use of hop cone extract obtained under supercritical CO2 conditions for producing antibacterial all-purpose cleaners

ABSTRACT This paper attempts to demonstrate empirically the possibility of using a hydrophobic extract of hop cone obtained under the conditions of supercritical carbon dioxide to produce all-purpose cleaner with antimicrobial activity and low irritant potential. A series of prototypes of products varied by the extract concentration was developed. The formulations were assessed for physicochemical properties: particle size, turbidity, and color. The results indicate that the hydrophobic extracts of hop cone can be a valuable component of chemical products intended for washing, having a broad spectrum of action and contributing to improvement of the product’s safety. GRAPHICAL ABSTRACT

Effects of Chemical Structure of Silicone Polyethers Used As Fabric Softener Additives on Selected Utility Properties of Cotton Fabric

Abstract The study addressed the effect of the structure of silicone polyethers on selected functional properties of cotton fabric rinsed in conditioners containing the additives under study. Fabric softener formulations containing two comb-structured compounds (PEG/PPG-14/0 Dimethicone and PEG/PPG-20/20 Dimethicone) and one block-structured compound (Bis-PEG/PPG-20/20 Dimethicone) were developed. Cotton fabric rinsed in conditioners containing silicone glycols was not found to be affected by yellowing. However, differences were noted in the softening ability and re-wettability of rinsed fabrics due to diverse structures of the additives used. The most desirable soft hand effect was observed after cotton rinsing in fabric softeners containing the block-structured compound Bis-PEG/PPG-20/20 Dimethicone. In contrast, the highest fabric re-wettability was shown for the conditioner enriched with a comb-structured compound (PEG/PPG-20/20 Dimethicone). The study results demonstrate that the prototypical fabric softeners containing silicone derivatives have a potential to provide quality characteristic required by consumers of this product group.

The Application of Hydrophobic Calendula Officinalis Flower Extract in the Manufacture of Handwashing Liquid Laundry Detergents

Liquid laundry detergents are aqueous solutions of surfactants and excipients. Currently, the market is witnessing a rapid development of products used in the washing process. Th is is mainly due to the constant competition of producers and constant changes in user preferences. Manufacturers, in order to meet the expectations of consumers increasingly introduce products of plant origin, which do not have a negative impact on both the user and the environment. Th e paper presents the results of research on the use of the marigold fl ower extract (Calendula offi cinalis Flower Extract) obtained under the conditions of supercritical carbon dioxide to produce handwashing laundry detergents. Th e substances included in this plant have a benefi cial eff ect of bactericidal and soothing. Th e study analysed the impact of the concentration of the extract on the selected physicochemical and usable properties of washing liquids (stability, viscosity, turbidity, washing ability and foaming performance). It was found that with increasing concentration of the extract we can observe a decrease in viscosity and foam-forming ability. Furthermore, with increasing extract concentration, growth of turbidity occurs. Th ere was no signifi cant eff ect of the extract concentrations in hand washing liquid on their detergency.