Structural-Mechanical Properties of Polyurethane Surface after Carbon Ion Subplantation

Ion-plasma modification of polymers has many potential applications, in particular, in the development of biomedical products. Treatment of soft polymers can easily damage the surface; low-energy plasma and subsequent investigation of the structural and mechanical properties of the surface are required. Polyurethane is a widely used block copolymer. Subplantation of carbon ions heterogeneously changes the structural and mechanical properties of the surface (relief, stiffness, thickness of the modified coating), forming a graphene-like nanolayer. Uniaxial deformation of the treated materials in some cases leads to the damage of the surface (local nanocracks, folds). Materials have increased hydrophobicity, good deformability (valid for certain treatment regimes) and can find application in design of products with improved biomedical properties.

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Improvement and Evaluation of Metal Thin Films by Very Low Energy Argon Ion Irradiation

Microelectromechanical Systems ◽

10.1115/imece2004-60417 ◽

2004 ◽

Author(s):

Tomonori Sasaki ◽

Ming Yang ◽

Kinuko Fujimoto

Keyword(s):

Thin Film ◽

Thin Films ◽

Mechanical Properties ◽

Ion Irradiation ◽

Metal Films ◽

Low Energy ◽

Metal Thin Films ◽

Ion Plasma ◽

Integrated Intensity ◽

Argon Ion

A new methodology using very low energy Ar ion irradiation is proposed to improve the mechanical properties of thin metal films deposited by sputtering. In this study, accelerating voltage of Ar ion plasma was set to lower than 100V, and several conditions were applied to irradiations. Consequently, it is found that Young’s modulus and hardness of Aluminum and Nickel thin film increases about 10% by the irradiation compared with a non-irradiated thin film. (111)–oriented integrated intensity of diffraction of Al and Ni thin film was increased by the irradiation. It is considered that crystalline orientation was changed and column spacing of the film be filled by the irradiation. It is shown that the proposed technique is effective to improve the mechanical properties of metal thin films with proper irradiation conditions.

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Low Energy Implantation of Carbon into Elastic Polyurethane

Coatings ◽

10.3390/coatings10030274 ◽

2020 ◽

Vol 10 (3) ◽

pp. 274 ◽

Cited By ~ 2

Author(s):

Ilya A. Morozov ◽

Alexander S. Kamenetskikh ◽

Anton Y. Beliaev ◽

Marina G. Scherban ◽

Dmitriy M. Kiselkov

Keyword(s):

Deformation Behavior ◽

Polymeric Materials ◽

Free Surface Energy ◽

Low Energy ◽

Carbon Ions ◽

Hard Phase ◽

Soft Phase ◽

Treatment Regimens ◽

Subsequent Investigation ◽

Induced Defects

Ion modification of polymeric materials requires gentle regimens and subsequent investigation of mechanical and deformation behavior of the surfaces. Polyurethane is a synthetic block copolymer: A fibrillar hard phase is inhomogeneoulsy distributed in a matrix of soft phase. Implantation of carbon ions into this polymer by deep oscillation magnetron sputtering (energy—0.1–1 keV and dose of ions—1014–1015 ion/cm2) forms graphene-like nanolayer and causes heterogeneous changes in structural and mechanical properties of the surface: Topography, elastic modulus and depth of implantation for the hard/soft phase areas are different. As a result, after certain treatment regimens strain-induced defects (nanocracks in the areas of the modified soft phase, or folds in the hard phase) appear on the surfaces of stretched materials. Treated surfaces have increased hydrophobicity and free surface energy, and in some cases show good deformability without any defects.

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Bubble Electrospinning and Bubble-Spun Nanofibers

Recent Patents on Nanotechnology ◽

10.2174/1872210513666191007114022 ◽

2020 ◽

Vol 14 (1) ◽

pp. 10-13 ◽

Cited By ~ 2

Author(s):

Lynn Y. Wan

Keyword(s):

Surface Tension ◽

Low Energy ◽

Efficient Technology ◽

High Productivity ◽

Needleless Electrospinning ◽

Polymeric Nanofibers ◽

Low Energy Consumption ◽

Potential Applications ◽

Surface Morphologies ◽

Unique Surface

Electrospinning is a highly efficient technology for fabrication of a wide variety of polymeric nanofibers. However, the development of traditional needle-based electrospinning has been hampered by its low productivity and need of tedious work dealing with needles cleaning, installation and uninstallation. As one of the most promising needleless electrospinning means, bubble electrospinning is known for its advantages of high productivity and relatively low energy consumption due to the introduction of a third force, air flow, as a major force overcoming the surface tension. In this paper, the restrictions of conventional electrospinning and the advantages of needleless electrospinning, especially the bubble electrospinning were elaborated. Reports and patents on bubble-spun nanofibers with unique surface morphologies were also reviewed in respect of their potential applications.

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A Slot-Die Technique for the Preparation of Continuous, High-Area, Chitosan-Based Thin Films

Polymers ◽

10.3390/polym13101566 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1566

Author(s):

Oliver J. Pemble ◽

Maria Bardosova ◽

Ian M. Povey ◽

Martyn E. Pemble

Keyword(s):

Thin Films ◽

Mechanical Properties ◽

High Volume ◽

Mechanical Anisotropy ◽

Diverse Range ◽

Direction Parallel ◽

High Area ◽

Wide Range ◽

Slot Die ◽

Potential Applications

Chitosan-based films have a diverse range of potential applications but are currently limited in terms of commercial use due to a lack of methods specifically designed to produce thin films in high volumes. To address this limitation directly, hydrogels prepared from chitosan, chitosan-tetraethoxy silane, also known as tetraethyl orthosilicate (TEOS) and chitosan-glutaraldehyde have been used to prepare continuous thin films using a slot-die technique which is described in detail. By way of preliminary analysis of the resulting films for comparison purposes with films made by other methods, the mechanical strength of the films produced was assessed. It was found that as expected, the hybrid films made with TEOS and glutaraldehyde both show a higher yield strength than the films made with chitosan alone. In all cases, the mechanical properties of the films were found to compare very favorably with similar measurements reported in the literature. In order to assess the possible influence of the direction in which the hydrogel passes through the slot-die on the mechanical properties of the films, testing was performed on plain chitosan samples cut in a direction parallel to the direction of travel and perpendicular to this direction. It was found that there was no evidence of any mechanical anisotropy induced by the slot die process. The examples presented here serve to illustrate how the slot-die approach may be used to create high-volume, high-area chitosan-based films cheaply and rapidly. It is suggested that an approach of the type described here may facilitate the use of chitosan-based films for a wide range of important applications.

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Effect on microstructural and mechanical properties of Inconel 718 superalloy fabricated by selective laser melting with rescanning by low energy density

Journal of Materials Research and Technology ◽

10.1016/j.jmrt.2020.12.053 ◽

2021 ◽

Vol 10 ◽

pp. 785-796

Author(s):

Jung Hyun Park ◽

Gyung Bae Bang ◽

Kee-Ahn Lee ◽

Yong Son ◽

Won Rae Kim ◽

...

Keyword(s):

Mechanical Properties ◽

Energy Density ◽

Selective Laser Melting ◽

Inconel 718 ◽

Low Energy ◽

Laser Melting ◽

Inconel 718 Superalloy

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The Infuence of Salicin on Rheological and Film-Forming Properties of Collagen

Molecules ◽

10.3390/molecules26061661 ◽

2021 ◽

Vol 26 (6) ◽

pp. 1661

Author(s):

Katarzyna Adamiak ◽

Katarzyna Lewandowska ◽

Alina Sionkowska

Keyword(s):

Mechanical Properties ◽

Atomic Force Microscopy ◽

Infrared Spectroscopy ◽

Rheological Properties ◽

Silver Carp ◽

Shear Tests ◽

Force Microscopy ◽

Atomic Force ◽

Film Forming ◽

Potential Applications

Collagen films are widely used as adhesives in medicine and cosmetology. However, its properties require modification. In this work, the influence of salicin on the properties of collagen solution and films was studied. Collagen was extracted from silver carp skin. The rheological properties of collagen solutions with and without salicin were characterized by steady shear tests. Thin collagen films were prepared by solvent evaporation. The structure of films was researched using infrared spectroscopy. The surface properties of films were investigated using Atomic Force Microscopy (AFM). Mechanical properties were measured as well. It was found that the addition of salicin modified the roughness of collagen films and their mechanical and rheological properties. The above-mentioned parameters are very important in potential applications of collagen films containing salicin.

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Smart Hydrogel Bilayers Prepared by Irradiation

Polymers ◽

10.3390/polym13111753 ◽

2021 ◽

Vol 13 (11) ◽

pp. 1753

Author(s):

Weixian Huo ◽

Heng An ◽

Shuquan Chang ◽

Shengsheng Yang ◽

Yin Huang ◽

...

Keyword(s):

Mechanical Properties ◽

Gamma Radiation ◽

Antibacterial Properties ◽

Cross Linking ◽

Temperature Sensitive ◽

Temperature Changes ◽

Smart Hydrogel ◽

Isopropyl Acrylamide ◽

Hydrogel Synthesis ◽

Potential Applications

Environment-responsive hydrogel actuators have attracted tremendous attention due to their intriguing properties. Gamma radiation has been considered as a green cross-linking process for hydrogel synthesis, as toxic cross-linking agents and initiators were not required. In this work, chitosan/agar/P(N-isopropyl acrylamide-co-acrylamide) (CS/agar/P(NIPAM-co-AM)) and CS/agar/Montmorillonite (MMT)/PNIPAM temperature-sensitive hydrogel bilayers were synthesized via gamma radiation at room temperature. The mechanical properties and temperature sensitivity of hydrogels under different agar content and irradiation doses were explored. The enhancement of the mechanical properties of the composite hydrogel can be attributed to the presence of agar and MMT. Due to the different temperature sensitivities provided by the two layers of hydrogel, they can move autonomously and act as a flexible gripper as the temperature changes. Thanks to the antibacterial properties of the hydrogel, their storage time and service life may be improved. The as prepared hydrogel bilayers have potential applications in control devices, soft robots, artificial muscles and other fields.

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