Low Energy Implantation of Carbon into Elastic Polyurethane

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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Structural-Mechanical Properties of Polyurethane Surface after Carbon Ion Subplantation

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.887.370 ◽

2021 ◽

Vol 887 ◽

pp. 370-375

Author(s):

I.A. Morozov ◽

A.S. Kamenetskikh

Keyword(s):

Mechanical Properties ◽

Surface Relief ◽

Low Energy ◽

Plasma Modification ◽

Carbon Ions ◽

Uniaxial Deformation ◽

Treatment Regimes ◽

Subsequent Investigation ◽

Ion Plasma ◽

Potential Applications

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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Sublinear response of peak 5 in LiF:Mg,Ti to low energy protons and carbon ions

Nuclear Instruments and Methods in Physics Research Section B Beam Interactions with Materials and Atoms ◽

10.1016/s0168-583x(04)00827-4 ◽

2004 ◽

Vol 226 (3) ◽

pp. 291-300

Author(s):

M RODRIGUEZVILLAFUERTE ◽

H ALVASANCHEZ ◽

O AVILA ◽

A BUENFIL ◽

O GALVAN ◽

...

Keyword(s):

Low Energy ◽

Carbon Ions

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Mesoscale bicontinuous networks in self-healing hydrogels delay fatigue fracture

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2000189117 ◽

2020 ◽

Vol 117 (14) ◽

pp. 7606-7612 ◽

Cited By ~ 3

Author(s):

Xueyu Li ◽

Kunpeng Cui ◽

Tao Lin Sun ◽

Lingpu Meng ◽

Chengtao Yu ◽

...

Keyword(s):

Fatigue Fracture ◽

Polymer Network ◽

Hierarchical Structures ◽

Soft Materials ◽

Biological Tissues ◽

Crack Advance ◽

Self Healing ◽

Hard Phase ◽

Soft Phase ◽

Simple Model System

Load-bearing biological tissues, such as muscles, are highly fatigue-resistant, but how the exquisite hierarchical structures of biological tissues contribute to their excellent fatigue resistance is not well understood. In this work, we study antifatigue properties of soft materials with hierarchical structures using polyampholyte hydrogels (PA gels) as a simple model system. PA gels are tough and self-healing, consisting of reversible ionic bonds at the 1-nm scale, a cross-linked polymer network at the 10-nm scale, and bicontinuous hard/soft phase networks at the 100-nm scale. We find that the polymer network at the 10-nm scale determines the threshold of energy release rateG0above which the crack grows, while the bicontinuous phase networks at the 100-nm scale significantly decelerate the crack advance until a transitionGtranfar aboveG0. In situ small-angle X-ray scattering analysis reveals that the hard phase network suppresses the crack advance to show decelerated fatigue fracture, andGtrancorresponds to the rupture of the hard phase network.

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Compression Strengthening of Plastic Bonded Explosives

Microscopy and Microanalysis ◽

10.1017/s1431927600013131 ◽

1997 ◽

Vol 3 (S2) ◽

pp. 1249-1250

Author(s):

Paul D. Peterson ◽

Deanne J. Idar ◽

John S. Gardner

Keyword(s):

Material Flow ◽

Compressive Loading ◽

Polymer Binder ◽

Material Behavior ◽

Inert Material ◽

Hard Phase ◽

Compressive Properties ◽

Soft Phase ◽

Mechanical Shocks ◽

Low Strain Rate

A recent study concluded that the most potentially dangerous scenarios for accidental detonation of a nuclear weapon were those involving weak thermal or mechanical shocks. For this reason, more data are needed to understand the material behavior of nuclear constituents under low strain rate scenarios.One of the components of many of these types of weapons is known as Plastic Bonded eXplosives (PBX). PBX is a paniculate composite material made of a hard phase explosive carried in a soft phase polymer binder. Recent work has showed that the stiffness of PBX increased under low rate compressive loading. This behavior was attributed to the shape of the test samples and cross-linking within the elastomer binder. Another theory proposed that the changing compressive properties could be attributed to the hard phase particles migrating together during material flow.Funk et al. demonstrated an inert material mock of PBX 9501, with the hard phase explosive replaced by granular sugar, also showed the same phenomena of compressive hardening.

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A Thermomechanical Modeling and Simulation of Viscoplastic Large Deformation Behavior for Polymeric Materials. 2nd Report, Vertex Model Based on Flow Rule and Its Finite Element Analysis.

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series A ◽

10.1299/kikaia.68.682 ◽

2002 ◽

Vol 68 (668) ◽

pp. 682-689 ◽

Cited By ~ 14

Author(s):

Daisuke MURAKAMI ◽

Seiichi KOBAYASHI ◽

Toshikazu TORIGAKI ◽

Kazuyuki SHIZAWA

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

Modeling And Simulation ◽

Large Deformation ◽

Deformation Behavior ◽

Polymeric Materials ◽

Flow Rule ◽

Vertex Model ◽

Element Analysis ◽

Thermomechanical Modeling

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Low-Energy Muons as a Tool for a Depth-Resolved Analysis of the SiO2/4H-SiC Interface

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1004.581 ◽

2020 ◽

Vol 1004 ◽

pp. 581-586

Author(s):

Judith Woerle ◽

Thomas Prokscha ◽

Ulrike Grossner

Keyword(s):

Depth Distribution ◽

Muon Spin ◽

Target Material ◽

Spin Rotation ◽

Low Energy ◽

Muon Spin Rotation ◽

Spatial Extension ◽

Thermal Oxide ◽

Induced Defects ◽

Thermally Grown

In this work, the potential of muon spin rotation (μSR) with low-energy muons (LE-μ) for the investigation of oxidation-induced defects at the SiO2/4H-SiC interface is explored. By using implantation energies for the muons in the keV range and comparing the fractions of muonium in different regions, the depth distribution of defects in the first 200 nm of the target material can be resolved. Defect profiles of interfaces with either deposited or thermally grown SiO2 layers on 4H-SiC are compared. The results show an increased number of defects in the case of a thermal oxide, both on the oxide and on the SiC side of the interface, with a spatial extension of a few tens of nm.

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