Surface properties of metal alloys used in aviation after plasma treatment

Plasma Processes & Polymers

Tomczyńska‐Mleko

et al. 2019

Albumin/gelatin gel (AG) properties are studied with an innovative cold‐plasma‐treatment‐based technique. Gel films are produced in situ on polyethylene terephthalate (PET) plates previously treated by gas (O2, air and Ar) cold plasma. After detaching the films from the surface, the contact angles of probe liquids are measured and wettability studied, based upon the induced changes of AG surface free energy. The effect of gelatin concentration in the AG is analysed. Oxygen‐cold‐plasma‐treated PET plates induce outstanding changes in wetting properties. Optical profilometry is used for the characterisation of surface topography. Dynamic oscillatory measurements help check for mesoscopic changes. The latter technique allows shaping of gel sample stiffness. The findings support a new methodology for biomaterials/biopolymer activation when unable to be exposed to the plasma working conditions.

“…Equilibrium contact angles were calculated from the measurements of advancing and receding contact angles on the mixed gel samples. For this purpose, eqs.…”

Section: Methodsmentioning

confidence: 99%

“…The advancing and receding contact angles were measured for up to 10 droplets of each probe liquid. [26] 2.6 | SFE determination Equilibrium contact angles were calculated from the measurements of advancing and receding contact angles [27] on the mixed gel samples. For this purpose, eqs.…”

Section: Contact Angle Measurementsmentioning

confidence: 99%

Surface modification of albumin/gelatin films gelled on low‐temperature plasma‐treated polyethylene terephthalate plates

Pérez‐Huertas

Plasma Processes & Polymers

Tomczyńska‐Mleko

et al. 2019

“…To calculate equilibrium contact angle Tadmor [15,16] theory was used. Tadmor proposed calculation of equilibrium International Journal of Polymer Science 3 contact angle [17][18][19]; (1a), (1b), and (1c) were used for this purpose.…”

Section: Determination Of Apparent Free Energymentioning

confidence: 99%

Apparent Surface Free Energy of Polymer/Paper Composite Material Treated by Air Plasma

International Journal of Polymer Science

2017

Surface plasma treatment consists in changes of surface properties without changing internal properties. In this paper composite polymer/paper material is used for production of packaging in cosmetic industry. There are problems with bonding this material at the time of packaging production due to its properties. Composite surface was treated by air plasma for 1, 10, 20, and 30 s. The advancing and receding contact angles of water, formamide, and diiodomethane were measured using both treated and untreated samples. Apparent surface free energy was estimated using the hysteresis (CAH) and Van Oss, Good, Chaudhury approaches (LWAB). Surface roughness was investigated using optical profilometry and identification of after plasma treatment emerging chemical groups was made by means of the XPS (X-ray photoelectron spectroscopy) technique. After plasma treatment the values of contact angles decreased which is particularly evident for polar liquids. Apparent surface free energy increased compared to that of untreated samples. Changes of energy value are due to the electron-donor parameter of energy. This parameter increases as a result of adding polar groups at the time of surface plasma activation. Changes of surface properties are combination of increase of polar chemical functional groups, increase on the surface, and surface roughness increase.

“…5). Apparent free energy was calculated using the equilibrium contact angles and two approaches [26]. Due to the change of surface composition (Tables 1, 2) and surface roughness, apparent surface free energy increases with the increasing gluten concentration.…”

Section: Surface Properties Of Biopolymersmentioning

confidence: 99%

Effect of gluten on the properties of ternary biopolymers based on gluten, whey protein concentrate, and kaolinite

Wesołowska–Trojanowska¹,

Tomczyńska‐Mleko

et al. 2017

Eur Food Res Technol

The texture was determined using the puncture test and the microstructure was analyzed by scanning electron microscopy. Surface properties of dried biopolymers were analyzed by surface wettability and roughness measurements. The increase in gluten concentration caused an increase in moduli and viscosity of the obtained wet biopolymers and in the puncture force for dry biopolymers. For the ternary biopolymer, layers with intercalation and exfoliation are observed in comparison with the biopolymer obtained without KAO. With the increasing Gl content in the biopolymer, the number of surface hydrophobic groups with carbon decreased and the number of surface hydrophilic groups increased. Higher Gl concentration produced less porous structure, although there are differences in the micro and nano-scale roughness. Water contact angle decreased with the increased Gl concentration, which is in agreement with less porous microstructure of the surface. The apparent surface free energy increased with the increasing of Gl concentration. The best plastic properties and the best shape of a pot were obtained for the ternary biopolymer with the 15% Gl concentration.