The Experts below are selected from a list of 11148 Experts worldwide ranked by ideXlab platform

Edmondo M Benetti - One of the best experts on this subject based on the ideXlab platform.

  • growing polymer brushes from a variety of substrates under ambient conditions by cu0 mediated surface initiated atrp
    ACS Applied Materials & Interfaces, 2019
    Co-Authors: Marco Fantin, Edmondo M Benetti, Nicholas D Spencer, Shivaprakash N. Ramakrishna, Krzysztof Matyjaszewski
    Abstract:

    Cu0-mediated surface-initiated atom transfer radical polymerization (Cu0 SI-ATRP) is a highly versatile, oxygen-tolerant, and extremely controlled polymer-grafting technique that enables the modification of flat inorganic surfaces, as well as porous organic and polymeric supports of different compositions. Exploiting the intimate contact between a Copper Plate, acting as a source of catalyst and reducing agent, and an initiator-bearing support, Cu0 SI-ATRP enables the rapid growth of biopassive, lubricious brushes from large flat surfaces, as well as from various organic supports, including cellulose fibers and elastomers, using microliter volumes of reaction mixtures, and without the need for deoxygenation of reaction mixtures or an inert atmosphere. Thanks to a detailed analysis of its mechanism and the parameters governing the polymerization process, polymer brush growth by Cu0 SI-ATRP can be precisely modulated and adapted to be applied to morphologically and chemically different substrates, setting u...

  • translating surface initiated atom transfer radical polymerization into technology the mechanism of cu0 mediated si atrp under environmental conditions
    ACS Macro Letters, 2019
    Co-Authors: Marco Fantin, Edmondo M Benetti, Nicholas D Spencer
    Abstract:

    The exceptional features of Cu0-mediated surface-initiated atom transfer radical polymerization (Cu0 SI-ATRP), and its potential for implementation in technologically relevant surface functionalizations are demonstrated thanks to a comprehensive understanding of its mechanism. Cu0 SI-ATRP enables the synthesis of multifunctional polymer brushes with a remarkable degree of control, over extremely large areas and without the need for inert atmosphere or deoxygenation of monomer solutions. When a polymerization mixture is placed between a flat Copper Plate and an ATRP-initiator-functionalized substrate, the vertical distance between these two overlaying surfaces determines the tolerance of the grafting process toward the oxygen, while the composition of the polymerization solution emerges as the critical parameter regulating polymer-grafting kinetics. At very small distances between the Copper Plate and the initiating surfaces, the oxygen dissolved in the solution is rapidly consumed via oxidation of the met...

  • fabrication and interfacial properties of polymer brush gradients by surface initiated cu 0 mediated controlled radical polymerization
    Macromolecules, 2017
    Co-Authors: Ella S. Dehghani, Nicholas D Spencer, Tao Zhang, Shivaprakash N. Ramakrishna, Rainer Jordan, Edmondo M Benetti
    Abstract:

    Surface-initiated Cu(0)-mediated controlled radical polymerization (Si-CuCRP) can be successfully applied to fabricate poly[(oligoethylene glycol)methyl ether methacrylate] (POEGMA) brushes in one pot, presenting a grafting-density gradient across the surface. This is achieved by continuously varying the distance (d) between a Copper Plate, used as a source of Cu species, and the initiator-functionalized substrate. X-ray photoelectron spectroscopy (XPS) analysis of monolayers of CuI-selective ligands demonstrates that a higher concentration of activator species diffuses to the initiating substrate in areas closer to the Copper Plate, a progressive decrease in activator concentration being observed upon increasing the distance between the two surfaces. As confirmed by the SI-CuCRP kinetics measured at different positions along the gradient, radical-termination reactions between propagating chains limit the grafting density of POEGMA grafts where the diffusion of activators is favored (i.e., at d → 0). This...

  • Fabrication and Interfacial Properties of Polymer Brush Gradients by Surface-Initiated Cu(0)-Mediated Controlled Radical Polymerization
    2017
    Co-Authors: Ella S. Dehghani, Nicholas D Spencer, Tao Zhang, Shivaprakash N. Ramakrishna, Rainer Jordan, Edmondo M Benetti
    Abstract:

    Surface-initiated Cu(0)-mediated controlled radical polymerization (Si-CuCRP) can be successfully applied to fabricate poly­[(oligoethylene glycol)­methyl ether methacrylate] (POEGMA) brushes in one pot, presenting a grafting-density gradient across the surface. This is achieved by continuously varying the distance (d) between a Copper Plate, used as a source of Cu species, and the initiator-functionalized substrate. X-ray photoelectron spectroscopy (XPS) analysis of monolayers of CuI-selective ligands demonstrates that a higher concentration of activator species diffuses to the initiating substrate in areas closer to the Copper Plate, a progressive decrease in activator concentration being observed upon increasing the distance between the two surfaces. As confirmed by the SI-CuCRP kinetics measured at different positions along the gradient, radical-termination reactions between propagating chains limit the grafting density of POEGMA grafts where the diffusion of activators is favored (i.e., at d → 0). This effect decreases with increasing d, ultimately yielding a gradual variation of POEGMA grafting density across the substrate. We have investigated the influence of grafting-density variation across the gradient on the swelling of POEGMA brushes as well as on their nanomechanical and nanotribological properties, measured by a combination of variable angle spectroscopic ellipsometry (VASE), colloidal-probe atomic force microscopy (CP-AFM), and lateral force microscopy (LFM). The results of these tests highlight how loosely grafted POEGMA chains incorporating a substantial amount of water can be significantly deformed by a shearing AFM probe, exhibit relatively high friction, and generate friction-vs-load (Ff–L) profiles that follow a sublinear trend described by a Johnson–Kendall–Roberts (JKR) modeltypical of deformable films of high surface energy. In contrast, more densely packed POEGMA brushes incorporate less solvent and display very low friction, with Ff–L data following a linear progression according to Amontons’ law

Qian Liming - One of the best experts on this subject based on the ideXlab platform.

  • multiply super anti corrosion nickel plating chromium part
    2015
    Co-Authors: Hao Jingjun, Qian Liming
    Abstract:

    The utility model discloses a multiply super anti -corrosion nickel plating - chromium part and manufacturing method, wherein multiply super anti -corrosion nickel plating - chromium part includes the substrate, preliminary treatment cladding material, its deposit are formed with the Copper Plate on preliminary treatment cladding material on whole substrate, and the basal layer, it is on the Copper Plate, and the functional layer, it is on the basal layer, and wherein the functional layer includes electronegative potential nickel dam and the microporous nickel layer on the electronegative potential nickel dam, and the decorative layer, it is on the microporous nickel layer, and the decorative layer is the arbitrary of trivalent chromium cladding material or hexavalent chromium cladding material. The utility model discloses an on the surperficial micropore that provides of parts, chromium plating process basis, increase the electronegative potential nickel coating to the corrosion resisting property of corrosion resisting property, the especially trivalent chromium product of product is improved, the more large -scale popularization and application of trivalent chromium product of more environmental protection can be makeeed.

  • nickel plating with or chromium part
    2015
    Co-Authors: Hao Jingjun, Qian Liming
    Abstract:

    The utility model discloses a nickel plating with or chromium part, this part includes the substrate, preliminary treatment cladding material, its deposit are formed with the Copper Plate on preliminary treatment cladding material on whole substrate, the functional layer, it is on the Copper Plate, and wherein the functional layer includes electronegative potential nickel dam and the microporous nickel layer on the electronegative potential nickel dam, and the decorative layer is on its formation and the microporous nickel layer. The utility model discloses a Plate common microporous nickel layer and the electronegative potential nickel dam that sets up in a top layer to very big improvement holistic corrosion resistance of part and stability, can also have good bright planarization simultaneously, cladding material combines effectually.

  • super anti corrosion nickel plating chromium part
    2015
    Co-Authors: Hao Jingjun, Qian Liming
    Abstract:

    The utility model relates to a super anti-corrosion nickel plating -chromium part belongs to and electroPlates technical field. It includes the substrate, preliminary treatment cladding material, its deposit are formed with the Copper Plate on preliminary treatment cladding material on whole substrate, with half light nickel dam, it is on the Copper Plate, with full gloss nickel dam or husky butyl's nickel dam, it is formed at half light nickel dam, and the functional layer, it is on full gloss nickel dam or husky butyl's nickel dam, and wherein the functional layer includes electronegative potential nickel dam and the microporous nickel layer on the electronegative potential nickel dam, and the decorative layer, it is on the microporous nickel layer. Potential difference between electronegative potential nickel dam and the microporous nickel layer is 10-120mv, the electronegative potential nickel dam in high-sulfur nickel dam, crazing line nickel dam the one deck or two-layer between the complex, when adopting the crazing line with high-sulfur nickel composite plating, the potential difference is 10-80mv between crazing line and the high-sulfur nickel. The outward appearance of both having guaranteed part microporous nickel layer is bright, makes it have super high corrosion resistance, hardness, wearability again.

  • nickel chromium plating part and manufacturing method thereof
    2015
    Co-Authors: Hao Jingjun, Qian Liming
    Abstract:

    The invention discloses a nickel-chromium plating part and a manufacturing method thereof. The nickel-chromium plating part includes a substrate, a pretreatment coating, a base layer, a functional layer and a decorative layer. The pretreatment coating is deposited on the entire substrate, and a Copper Plate layer is formed on the pretreatment coating; the base layer is formed on the Copper Plate layer; the functional layer is formed on the base layer and includes a low potential nickel layer and a microporous nickel layer formed on the low potential nickel layer; and the decorative layer is formed on the microporous nickel layer and is a trivalent chromium coating or a hexavalent chromium coating. Based on the micropores on the part surface and chrome plating technology, the low potential nickel layer is added to improve the corrosion resistance of the product, especially the corrosion resistance of trivalent chromium plating product, so as to promote the large scale popularization and application of the trivalent chromium product, which has better environmental protection performance.

  • multilayer ultra corrosion resistant nickel chromium plating part and manufacturing method thereof
    2015
    Co-Authors: Hao Jingjun, Qian Liming
    Abstract:

    The invention discloses a multilayer ultra corrosion resistant nickel-chromium plating part and a manufacturing method thereof. The multilayer ultra corrosion resistant nickel-chromium plating part includes a substrate, a pretreatment coating, a base layer, a functional layer and a decorative layer. The pretreatment coating is deposited on the entire substrate, and a Copper Plate layer is formed on the pretreatment coating; the base layer is formed on the Copper Plate layer; the functional layer is formed on the base layer and includes a low potential nickel layer and a microporous nickel layer formed on the low potential nickel layer; and the decorative layer is formed on the microporous nickel layer and is a trivalent chromium coating or a hexavalent chromium coating. Based on the micropores on the part surface and chrome plating technology, the low potential nickel layer is added to improve the corrosion resistance of the product, especially the corrosion resistance of trivalent chromium plating product, so as to promote the large scale popularization and application of the trivalent chromium product, which has better environmental protection performance.

Hao Jingjun - One of the best experts on this subject based on the ideXlab platform.

  • multiply super anti corrosion nickel plating chromium part
    2015
    Co-Authors: Hao Jingjun, Qian Liming
    Abstract:

    The utility model discloses a multiply super anti -corrosion nickel plating - chromium part and manufacturing method, wherein multiply super anti -corrosion nickel plating - chromium part includes the substrate, preliminary treatment cladding material, its deposit are formed with the Copper Plate on preliminary treatment cladding material on whole substrate, and the basal layer, it is on the Copper Plate, and the functional layer, it is on the basal layer, and wherein the functional layer includes electronegative potential nickel dam and the microporous nickel layer on the electronegative potential nickel dam, and the decorative layer, it is on the microporous nickel layer, and the decorative layer is the arbitrary of trivalent chromium cladding material or hexavalent chromium cladding material. The utility model discloses an on the surperficial micropore that provides of parts, chromium plating process basis, increase the electronegative potential nickel coating to the corrosion resisting property of corrosion resisting property, the especially trivalent chromium product of product is improved, the more large -scale popularization and application of trivalent chromium product of more environmental protection can be makeeed.

  • nickel plating with or chromium part
    2015
    Co-Authors: Hao Jingjun, Qian Liming
    Abstract:

    The utility model discloses a nickel plating with or chromium part, this part includes the substrate, preliminary treatment cladding material, its deposit are formed with the Copper Plate on preliminary treatment cladding material on whole substrate, the functional layer, it is on the Copper Plate, and wherein the functional layer includes electronegative potential nickel dam and the microporous nickel layer on the electronegative potential nickel dam, and the decorative layer is on its formation and the microporous nickel layer. The utility model discloses a Plate common microporous nickel layer and the electronegative potential nickel dam that sets up in a top layer to very big improvement holistic corrosion resistance of part and stability, can also have good bright planarization simultaneously, cladding material combines effectually.

  • super anti corrosion nickel plating chromium part
    2015
    Co-Authors: Hao Jingjun, Qian Liming
    Abstract:

    The utility model relates to a super anti-corrosion nickel plating -chromium part belongs to and electroPlates technical field. It includes the substrate, preliminary treatment cladding material, its deposit are formed with the Copper Plate on preliminary treatment cladding material on whole substrate, with half light nickel dam, it is on the Copper Plate, with full gloss nickel dam or husky butyl's nickel dam, it is formed at half light nickel dam, and the functional layer, it is on full gloss nickel dam or husky butyl's nickel dam, and wherein the functional layer includes electronegative potential nickel dam and the microporous nickel layer on the electronegative potential nickel dam, and the decorative layer, it is on the microporous nickel layer. Potential difference between electronegative potential nickel dam and the microporous nickel layer is 10-120mv, the electronegative potential nickel dam in high-sulfur nickel dam, crazing line nickel dam the one deck or two-layer between the complex, when adopting the crazing line with high-sulfur nickel composite plating, the potential difference is 10-80mv between crazing line and the high-sulfur nickel. The outward appearance of both having guaranteed part microporous nickel layer is bright, makes it have super high corrosion resistance, hardness, wearability again.

  • nickel chromium plating part and manufacturing method thereof
    2015
    Co-Authors: Hao Jingjun, Qian Liming
    Abstract:

    The invention discloses a nickel-chromium plating part and a manufacturing method thereof. The nickel-chromium plating part includes a substrate, a pretreatment coating, a base layer, a functional layer and a decorative layer. The pretreatment coating is deposited on the entire substrate, and a Copper Plate layer is formed on the pretreatment coating; the base layer is formed on the Copper Plate layer; the functional layer is formed on the base layer and includes a low potential nickel layer and a microporous nickel layer formed on the low potential nickel layer; and the decorative layer is formed on the microporous nickel layer and is a trivalent chromium coating or a hexavalent chromium coating. Based on the micropores on the part surface and chrome plating technology, the low potential nickel layer is added to improve the corrosion resistance of the product, especially the corrosion resistance of trivalent chromium plating product, so as to promote the large scale popularization and application of the trivalent chromium product, which has better environmental protection performance.

  • multilayer ultra corrosion resistant nickel chromium plating part and manufacturing method thereof
    2015
    Co-Authors: Hao Jingjun, Qian Liming
    Abstract:

    The invention discloses a multilayer ultra corrosion resistant nickel-chromium plating part and a manufacturing method thereof. The multilayer ultra corrosion resistant nickel-chromium plating part includes a substrate, a pretreatment coating, a base layer, a functional layer and a decorative layer. The pretreatment coating is deposited on the entire substrate, and a Copper Plate layer is formed on the pretreatment coating; the base layer is formed on the Copper Plate layer; the functional layer is formed on the base layer and includes a low potential nickel layer and a microporous nickel layer formed on the low potential nickel layer; and the decorative layer is formed on the microporous nickel layer and is a trivalent chromium coating or a hexavalent chromium coating. Based on the micropores on the part surface and chrome plating technology, the low potential nickel layer is added to improve the corrosion resistance of the product, especially the corrosion resistance of trivalent chromium plating product, so as to promote the large scale popularization and application of the trivalent chromium product, which has better environmental protection performance.

Sean Mauch - One of the best experts on this subject based on the ideXlab platform.

  • large scale fluid structure interaction simulation of viscoplastic and fracturing thin shells subjected to shocks and detonations
    Computers & Structures, 2007
    Co-Authors: Fehmi Cirak, Ralf Deiterding, Sean Mauch
    Abstract:

    The fluid-structure interaction simulation of shock- and detonation-loaded thin-walled structures requires numerical methods that can cope with large deformations as well as local topology changes. We present a robust level-set-based approach that integrates a Lagrangian thin-shell finite element solver with fracture and fragmentation capabilities and an Eulerian Cartesian fluid solver with optional dynamic mesh adaptation. As computational applications, we consider the plastic deformation of a Copper Plate impacted by a strong piston-induced pressure wave inside a water pipe; and the induction of large plastic deformations and rupture of thin aluminum tubes due to the passage of ethylene-oxygen detonations.

  • large scale fluid structure interaction simulation of viscoplastic and fracturing thin shells subjected to shocks and detonations
    Computers & Structures, 2007
    Co-Authors: Fehmi Cirak, Ralf Deiterding, Sean Mauch
    Abstract:

    The fluid-structure interaction simulation of shock- and detonation-loaded thin-walled structures requires numerical methods that can cope with large deformations as well as local topology changes. We present a robust level-set-based approach that integrates a Lagrangian thin-shell finite element solver with fracture and fragmentation capabilities and an Eulerian Cartesian fluid solver with optional dynamic mesh adaptation. As computational applications, we consider the plastic deformation of a Copper Plate impacted by a strong piston-induced pressure wave inside a water pipe; and the induction of large plastic deformations and rupture of thin aluminum tubes due to the passage of ethylene-oxygen detonations.

Rainer Jordan - One of the best experts on this subject based on the ideXlab platform.

  • fabrication and interfacial properties of polymer brush gradients by surface initiated cu 0 mediated controlled radical polymerization
    Macromolecules, 2017
    Co-Authors: Ella S. Dehghani, Nicholas D Spencer, Tao Zhang, Shivaprakash N. Ramakrishna, Rainer Jordan, Edmondo M Benetti
    Abstract:

    Surface-initiated Cu(0)-mediated controlled radical polymerization (Si-CuCRP) can be successfully applied to fabricate poly[(oligoethylene glycol)methyl ether methacrylate] (POEGMA) brushes in one pot, presenting a grafting-density gradient across the surface. This is achieved by continuously varying the distance (d) between a Copper Plate, used as a source of Cu species, and the initiator-functionalized substrate. X-ray photoelectron spectroscopy (XPS) analysis of monolayers of CuI-selective ligands demonstrates that a higher concentration of activator species diffuses to the initiating substrate in areas closer to the Copper Plate, a progressive decrease in activator concentration being observed upon increasing the distance between the two surfaces. As confirmed by the SI-CuCRP kinetics measured at different positions along the gradient, radical-termination reactions between propagating chains limit the grafting density of POEGMA grafts where the diffusion of activators is favored (i.e., at d → 0). This...

  • Fabrication and Interfacial Properties of Polymer Brush Gradients by Surface-Initiated Cu(0)-Mediated Controlled Radical Polymerization
    2017
    Co-Authors: Ella S. Dehghani, Nicholas D Spencer, Tao Zhang, Shivaprakash N. Ramakrishna, Rainer Jordan, Edmondo M Benetti
    Abstract:

    Surface-initiated Cu(0)-mediated controlled radical polymerization (Si-CuCRP) can be successfully applied to fabricate poly­[(oligoethylene glycol)­methyl ether methacrylate] (POEGMA) brushes in one pot, presenting a grafting-density gradient across the surface. This is achieved by continuously varying the distance (d) between a Copper Plate, used as a source of Cu species, and the initiator-functionalized substrate. X-ray photoelectron spectroscopy (XPS) analysis of monolayers of CuI-selective ligands demonstrates that a higher concentration of activator species diffuses to the initiating substrate in areas closer to the Copper Plate, a progressive decrease in activator concentration being observed upon increasing the distance between the two surfaces. As confirmed by the SI-CuCRP kinetics measured at different positions along the gradient, radical-termination reactions between propagating chains limit the grafting density of POEGMA grafts where the diffusion of activators is favored (i.e., at d → 0). This effect decreases with increasing d, ultimately yielding a gradual variation of POEGMA grafting density across the substrate. We have investigated the influence of grafting-density variation across the gradient on the swelling of POEGMA brushes as well as on their nanomechanical and nanotribological properties, measured by a combination of variable angle spectroscopic ellipsometry (VASE), colloidal-probe atomic force microscopy (CP-AFM), and lateral force microscopy (LFM). The results of these tests highlight how loosely grafted POEGMA chains incorporating a substantial amount of water can be significantly deformed by a shearing AFM probe, exhibit relatively high friction, and generate friction-vs-load (Ff–L) profiles that follow a sublinear trend described by a Johnson–Kendall–Roberts (JKR) modeltypical of deformable films of high surface energy. In contrast, more densely packed POEGMA brushes incorporate less solvent and display very low friction, with Ff–L data following a linear progression according to Amontons’ law

  • surface initiated cu 0 mediated controlled radical polymerization si cucrp using a Copper Plate
    Polymer Chemistry, 2015
    Co-Authors: Tao Zhang, Felix Muller, Ihsan Amin, Rainer Jordan
    Abstract:

    Surface engineering with polymer brushes has become one of the most versatile techniques to tailor surface properties of substrates for a broad variety of (bio-) technological applications. We report on a new facile approach to prepare defined and dense polymer brushes on planar substrates by surface-initiated Cu(0) mediated controlled radical polymerization (SI-CuCRP) of numerous vinyl monomers using a Copper Plate at room temperature. The fabrication of a variety of homo-, block, gradient and patterned polymer brushes as well as polymer brush arrays is demonstrated. The SI-CuCRP was found to be strictly surface-confined, of highly living character, proceeds remarkably fast and results in polymer brushes of very high grafting densities. The brush layer thickness can be modulated by the polymerization time or by the distance of the Copper Plate to the modified substrate. As the Copper Plate can be reused multiple times, no additional Copper salts are added and only minimal amount of chemicals is needed, the simple and low-cost experimental conditions allows researchers from various fields to prepare tailored polymer brush surfaces for their needs.