The Experts below are selected from a list of 66294 Experts worldwide ranked by ideXlab platform
A Somoza - One of the best experts on this subject based on the ideXlab platform.
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natural rubber styrene butadiene rubber blends prepared by Solution Mixing influence of vulcanization temperature using a semi ev sulfur curing system on the microstructural properties
Polymer Testing, 2017Co-Authors: M A Mansilla, A J Marzocca, Carlos Eugenio Macchi, A SomozaAbstract:Abstract Blends of natural rubber (NR) and styrene-butadiene rubber (SBR) were prepared by Solution Mixing and vulcanized with sulfur and accelerator in a Semi-EV system at 433 K and 443 K in order to study the vulcanization kinetic and the influence of vulcanization temperature on final structure of the blends. The vulcanization kinetic studied through the variation in rheometer curves was analyzed using the Ding and Leonov model, which takes into account the reversion effect during the cure process. The average free nanohole volume and the fractional free volume of samples with different NR/SBR ratio were estimated using positron annihilation lifetime spectroscopy (PALS). Also, the crosslink density was determined by means of swelling tests in a solvent. For all the compounds, a correlation between the free nanohole volume and the delta torque obtained from the respective rheometer curves was established.
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Natural rubber/styrene-butadiene rubber blends prepared by Solution Mixing: Influence of vulcanization temperature using a Semi-EV sulfur curing system on the microstructural properties
Polymer Testing, 2017Co-Authors: M A Mansilla, A J Marzocca, Carlos Eugenio Macchi, A SomozaAbstract:Abstract Blends of natural rubber (NR) and styrene-butadiene rubber (SBR) were prepared by Solution Mixing and vulcanized with sulfur and accelerator in a Semi-EV system at 433 K and 443 K in order to study the vulcanization kinetic and the influence of vulcanization temperature on final structure of the blends. The vulcanization kinetic studied through the variation in rheometer curves was analyzed using the Ding and Leonov model, which takes into account the reversion effect during the cure process. The average free nanohole volume and the fractional free volume of samples with different NR/SBR ratio were estimated using positron annihilation lifetime spectroscopy (PALS). Also, the crosslink density was determined by means of swelling tests in a solvent. For all the compounds, a correlation between the free nanohole volume and the delta torque obtained from the respective rheometer curves was established.
Sherif Araby - One of the best experts on this subject based on the ideXlab platform.
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electrically and thermally conductive elastomer graphene nanocomposites by Solution Mixing
Polymer, 2014Co-Authors: Sherif Araby, Qingshi Meng, Liqun Zhang, Hailan Kang, Peter Majewski, Youhong TangAbstract:Abstract The greatest challenge in developing polymer/graphene nanocomposites is to prevent graphene layers stacking; in this respect, we found effective Solution-Mixing polymers with cost-effective graphene of hydrophobic surface. Since graphene oxide is hydrophilic and in need of reduction, highly conducing graphene platelets (GnPs) of ∼3 nm in thickness were selected to Solution-mix with a commonly used elastomer – styrene–butadiene rubber (SBR). A percolation threshold of electrical conductivity was observed at 5.3 vol% of GnPs, and the SBR thermal conductivity enhanced three times at 24 vol%. Tensile strength, Young's modulus and tear strength were improved by 413%, 782% and 709%, respectively, at 16.7 vol%. Payne effect, an important design criteria for elastomers used in dynamic loading environment, was also investigated. The comparison of Solution Mixing with melt compounding, where the same starting materials were used, demonstrated that Solution Mixing is more effective in promoting the reinforcing effect of GnPs, since it provides more interlayer spacing for elastomer molecules intercalating and retains the high aspect ratio of GnPs leading to filler–filler network at a low volume fraction. We also compared the reinforcing effect of GnPs with those of carbon black and carbon nanotubes.
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Electrically and thermally conductive elastomer/graphene nanocomposites by Solution Mixing
Polymer, 2014Co-Authors: Sherif Araby, Qingshi Meng, Liqun Zhang, Hailan Kang, Peter Majewski, Youhong TangAbstract:Abstract The greatest challenge in developing polymer/graphene nanocomposites is to prevent graphene layers stacking; in this respect, we found effective Solution-Mixing polymers with cost-effective graphene of hydrophobic surface. Since graphene oxide is hydrophilic and in need of reduction, highly conducing graphene platelets (GnPs) of ∼3 nm in thickness were selected to Solution-mix with a commonly used elastomer – styrene–butadiene rubber (SBR). A percolation threshold of electrical conductivity was observed at 5.3 vol% of GnPs, and the SBR thermal conductivity enhanced three times at 24 vol%. Tensile strength, Young's modulus and tear strength were improved by 413%, 782% and 709%, respectively, at 16.7 vol%. Payne effect, an important design criteria for elastomers used in dynamic loading environment, was also investigated. The comparison of Solution Mixing with melt compounding, where the same starting materials were used, demonstrated that Solution Mixing is more effective in promoting the reinforcing effect of GnPs, since it provides more interlayer spacing for elastomer molecules intercalating and retains the high aspect ratio of GnPs leading to filler–filler network at a low volume fraction. We also compared the reinforcing effect of GnPs with those of carbon black and carbon nanotubes.
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Electrical conductivity and mechanical performance of polymer/graphene composites developed by two compounding methods
Recent Advances in Structural Integrity Analysis - Proceedings of the International Congress (APCF SIF-2014), 2014Co-Authors: Sherif Araby, Q. MengAbstract:In this work we demonstrated how to utilise graphene platelets by melt compounding and Solution Mixing to develop polymer composites based on a commercial elastomer, styrene-butadiene rubber (SBR) which has inherently low stiffness and strength. The electrical volume resistivity decreased abruptly by several orders of magnitude at ~ 5.3 vol% in the case of composites made by Solution Mixing and at ~ 17 vol% for the melt-compounding composites, confirming the formation of conductive networks in the matrices. Nearly all the mechanical measurements for the Solution-Mixing composites except the fracture strain demonstrated higher improvements than those for the melt-compounding composites.
Youhong Tang - One of the best experts on this subject based on the ideXlab platform.
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electrically and thermally conductive elastomer graphene nanocomposites by Solution Mixing
Polymer, 2014Co-Authors: Sherif Araby, Qingshi Meng, Liqun Zhang, Hailan Kang, Peter Majewski, Youhong TangAbstract:Abstract The greatest challenge in developing polymer/graphene nanocomposites is to prevent graphene layers stacking; in this respect, we found effective Solution-Mixing polymers with cost-effective graphene of hydrophobic surface. Since graphene oxide is hydrophilic and in need of reduction, highly conducing graphene platelets (GnPs) of ∼3 nm in thickness were selected to Solution-mix with a commonly used elastomer – styrene–butadiene rubber (SBR). A percolation threshold of electrical conductivity was observed at 5.3 vol% of GnPs, and the SBR thermal conductivity enhanced three times at 24 vol%. Tensile strength, Young's modulus and tear strength were improved by 413%, 782% and 709%, respectively, at 16.7 vol%. Payne effect, an important design criteria for elastomers used in dynamic loading environment, was also investigated. The comparison of Solution Mixing with melt compounding, where the same starting materials were used, demonstrated that Solution Mixing is more effective in promoting the reinforcing effect of GnPs, since it provides more interlayer spacing for elastomer molecules intercalating and retains the high aspect ratio of GnPs leading to filler–filler network at a low volume fraction. We also compared the reinforcing effect of GnPs with those of carbon black and carbon nanotubes.
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Electrically and thermally conductive elastomer/graphene nanocomposites by Solution Mixing
Polymer, 2014Co-Authors: Sherif Araby, Qingshi Meng, Liqun Zhang, Hailan Kang, Peter Majewski, Youhong TangAbstract:Abstract The greatest challenge in developing polymer/graphene nanocomposites is to prevent graphene layers stacking; in this respect, we found effective Solution-Mixing polymers with cost-effective graphene of hydrophobic surface. Since graphene oxide is hydrophilic and in need of reduction, highly conducing graphene platelets (GnPs) of ∼3 nm in thickness were selected to Solution-mix with a commonly used elastomer – styrene–butadiene rubber (SBR). A percolation threshold of electrical conductivity was observed at 5.3 vol% of GnPs, and the SBR thermal conductivity enhanced three times at 24 vol%. Tensile strength, Young's modulus and tear strength were improved by 413%, 782% and 709%, respectively, at 16.7 vol%. Payne effect, an important design criteria for elastomers used in dynamic loading environment, was also investigated. The comparison of Solution Mixing with melt compounding, where the same starting materials were used, demonstrated that Solution Mixing is more effective in promoting the reinforcing effect of GnPs, since it provides more interlayer spacing for elastomer molecules intercalating and retains the high aspect ratio of GnPs leading to filler–filler network at a low volume fraction. We also compared the reinforcing effect of GnPs with those of carbon black and carbon nanotubes.
Baofeng Lin - One of the best experts on this subject based on the ideXlab platform.
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preparation of carboxylic styrene butadiene rubber chitosan composites with dense supramolecular network via Solution Mixing process
Composites Part A-applied Science and Manufacturing, 2019Co-Authors: Jiada Nie, Baofeng LinAbstract:Abstract A novel supramolecular network based on carboxylic styrene butadiene rubber (XSBR) and chitosan (CTS) is prepared through Solution Mixing process. XSBR molecular chains have strong interactions with extended CTS via the formation of ammonium carboxylates bridging crosslinks and hydrogen bonds, which efficiently prevent extended CTS from reagglomerating. Compared with CTS nanoparticles, unfolded CTS expose more amino and hydroxyl groups to XSBR, which results in a denser and stronger network structure. However, because of the rigidity of CTS molecule, unfolded CTS construct a rigid framing in the supramolecular network, which reduces the extensibility of the XSBR/CTS composites. Interestingly, the Solution Mixing retains abundant air bubbles in the XSBR/CTS Solution, which turns out a porous composite.
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Preparation of carboxylic styrene butadiene rubber/chitosan composites with dense supramolecular network via Solution Mixing process
Composites Part A: Applied Science and Manufacturing, 2019Co-Authors: Jiada Nie, Baofeng LinAbstract:Abstract A novel supramolecular network based on carboxylic styrene butadiene rubber (XSBR) and chitosan (CTS) is prepared through Solution Mixing process. XSBR molecular chains have strong interactions with extended CTS via the formation of ammonium carboxylates bridging crosslinks and hydrogen bonds, which efficiently prevent extended CTS from reagglomerating. Compared with CTS nanoparticles, unfolded CTS expose more amino and hydroxyl groups to XSBR, which results in a denser and stronger network structure. However, because of the rigidity of CTS molecule, unfolded CTS construct a rigid framing in the supramolecular network, which reduces the extensibility of the XSBR/CTS composites. Interestingly, the Solution Mixing retains abundant air bubbles in the XSBR/CTS Solution, which turns out a porous composite.
M A Mansilla - One of the best experts on this subject based on the ideXlab platform.
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natural rubber styrene butadiene rubber blends prepared by Solution Mixing influence of vulcanization temperature using a semi ev sulfur curing system on the microstructural properties
Polymer Testing, 2017Co-Authors: M A Mansilla, A J Marzocca, Carlos Eugenio Macchi, A SomozaAbstract:Abstract Blends of natural rubber (NR) and styrene-butadiene rubber (SBR) were prepared by Solution Mixing and vulcanized with sulfur and accelerator in a Semi-EV system at 433 K and 443 K in order to study the vulcanization kinetic and the influence of vulcanization temperature on final structure of the blends. The vulcanization kinetic studied through the variation in rheometer curves was analyzed using the Ding and Leonov model, which takes into account the reversion effect during the cure process. The average free nanohole volume and the fractional free volume of samples with different NR/SBR ratio were estimated using positron annihilation lifetime spectroscopy (PALS). Also, the crosslink density was determined by means of swelling tests in a solvent. For all the compounds, a correlation between the free nanohole volume and the delta torque obtained from the respective rheometer curves was established.
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Natural rubber/styrene-butadiene rubber blends prepared by Solution Mixing: Influence of vulcanization temperature using a Semi-EV sulfur curing system on the microstructural properties
Polymer Testing, 2017Co-Authors: M A Mansilla, A J Marzocca, Carlos Eugenio Macchi, A SomozaAbstract:Abstract Blends of natural rubber (NR) and styrene-butadiene rubber (SBR) were prepared by Solution Mixing and vulcanized with sulfur and accelerator in a Semi-EV system at 433 K and 443 K in order to study the vulcanization kinetic and the influence of vulcanization temperature on final structure of the blends. The vulcanization kinetic studied through the variation in rheometer curves was analyzed using the Ding and Leonov model, which takes into account the reversion effect during the cure process. The average free nanohole volume and the fractional free volume of samples with different NR/SBR ratio were estimated using positron annihilation lifetime spectroscopy (PALS). Also, the crosslink density was determined by means of swelling tests in a solvent. For all the compounds, a correlation between the free nanohole volume and the delta torque obtained from the respective rheometer curves was established.