The Experts below are selected from a list of 312 Experts worldwide ranked by ideXlab platform
Akira Isogai - One of the best experts on this subject based on the ideXlab platform.
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diverse nanocelluloses prepared from tempo oxidized wood cellulose fibers nanonetworks nanofibers and nanocrystals
Current Opinion in Solid State & Materials Science, 2019Co-Authors: Akira Isogai, Yaxin ZhouAbstract:Abstract When wood cellulose fibers are oxidized with NaClO and catalytic amounts of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) and NaBr in water at pH 10, significant amounts of Sodium Carboxylate groups (≤1.7 mmol/g) are introduced into the oxidized celluloses. The original fibrous morphologies and cellulose I crystal structures are unchanged by oxidation. The TEMPO-oxidized cellulose fibers can be converted to partially fibrillated nanonetworks, completely individualized cellulose nanofibers with high aspect ratios, and needle-like cellulose nanocrystals with low aspect ratios by controlling the conditions of mechanical disintegration in water. It is therefore possible to prepare diverse nanocelluloses with different morphologies and properties from the same TEMPO-oxidized cellulose fibers, for various end uses and applications. All TEMPO-oxidized nanocelluloses contain large amounts of Carboxylate groups. These provide scaffolds for versatile surface modification of nanocelluloses by simple ion exchange of Sodium for other metal ions and alkylammonium ions.
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preparation of cellulose nanofibers using green and sustainable chemistry
Green and Sustainable Chemistry, 2018Co-Authors: Akira Isogai, Lennart BergstromAbstract:The development of green and sustainable routes to liberate crystalline cellulose microfibrils from plant cell walls is of utmost importance to enable development of the large-scale production of sustainable nanomaterials based on renewable resources. The catalytic oxidation of cellulose using 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO) under aqueous conditions at room temperature is a position-selective and efficient chemical modification. TEMPO-mediated oxidation of plant cellulose fibers, followed by gentle mechanical disintegration of the oxidized celluloses in water, results in the formation of TEMPO-oxidized cellulose nanofibers (TOCNs) with homogeneous widths (∼3 nm) and high aspect ratios. TOCNs are characteristic bio-based materials with high tensile strengths and elastic moduli. Sodium Carboxylate groups are densely present on the crystalline TOCN surfaces and can undergo counterion exchange from Sodium to other metal or alkylammonium ions under aqueous conditions. The hydrophilic/hydrophobic, stable/biodegradable, super deodorant, catalytic, and other functionalities of TOCNs can be controlled through counterion exchange.
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Development of completely dispersed cellulose nanofibers.
Proceedings of the Japan Academy. Series B Physical and biological sciences, 2018Co-Authors: Akira IsogaiAbstract:: Plant cellulose fibers of width and length ∼0.03 mm and ∼3 mm, respectively, can be completely converted to individual cellulose nanofibers of width and length ∼3 nm and ∼1 µm, respectively, by 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO)-mediated oxidation under aqueous conditions and subsequent gentle mechanical disintegration of the oxidized cellulose in water. The obtained TEMPO-oxidized cellulose nanofibers (TOCNs) are new bio-based, crystalline nanomaterials with applications in the high-tech and commodity product industries. Sodium Carboxylate groups, which are densely, regularly, and position-selectively present on the crystalline TOCN surfaces, can be efficiently ion-exchanged with other metal and alkylammonium Carboxylate groups in water to control the biodegradable/stable and hydrophilic/hydrophobic properties of the TOCNs. TOCNs are therefore promising nanomaterials that can be prepared from the abundant wood biomass resources present in Japan. Increased production and use of TOCNs would stimulate a new material stream from forestry to industries, helping to establish a sustainable society based on wood biomass resources.
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Luminescent and Transparent Nanocellulose Films Containing Europium Carboxylate Groups as Flexible Dielectric Materials
2018Co-Authors: Quanling Yang, Tsuguyuki Saito, Chenggang Zhang, Zhuqun Shi, Jinyu Wang, Chuanxi Xiong, Akira IsogaiAbstract:Transparent, flexible, and luminescent 2,2,6,6-tetramethylpiperidine-1-oxyl radical-oxidized cellulose nanofibril films with europium Carboxylate groups (TOCN-Eu) are proposed as potential flexible dielectric materials. The TOCN-Eu films were prepared from TOCN films with Sodium Carboxylate groups (TOCN-Na) by immersion in Eu(NO3)3 solution and subsequent washing with water and drying of the wet TOCN-Eu hydrogel films. The nanolayered TOCN-Eu films emit red light under ultraviolet-light irradiation and exhibit greatly improved dry and wet mechanical properties, water resistance, thermal stability, oxygen-barrier properties, dielectric breakdown strength, and energy density than conventional TOCN-Na films. These characteristic properties of the TOCN-Eu films are most likely caused by the formation of strong ionic bonds between the Carboxylate groups and Eu3+ ions. These high-performance cellulose nanofibril films are promising for application as multifunctional materials in light-emitting, photovoltaic, and energy storage devices
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water resistant and high oxygen barrier nanocellulose films with interfibrillar cross linkages formed through multivalent metal ions
Journal of Membrane Science, 2016Co-Authors: Michiko Shimizu, Tsuguyuki Saito, Akira IsogaiAbstract:Abstract Once-dried 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized cellulose nanofibril (TOCN) films with Sodium Carboxylate groups (TOCN–COONa) were soaked in aqueous MgCl2, CaCl2, AlCl3 and FeCl3 solutions to change the counterion to TOCNs–COOM films (M: metal ion). Dry TOCN–COOM films had high Young's moduli (11–20 GPa) and tensile strength (170–280 MPa). In particular, the wet TOCN films with aluminum and iron (III) Carboxylates had high Young's moduli and tensile strengths of ~3 GPa and 30–40 MPa, respectively, even at water contents of ~470%. Moreover, the dry TOCN films with calcium and aluminum Carboxylates had extremely low oxygen permeabilities of 0.08 and 0.15 mL µm m−2 day−1 kPa−1, respectively, even at 80% relative humidity, which are outstanding values compared to those of other films reported previously. These results are explained in terms of the high water resistance of the films, which is caused by the formation of interfibrillar cross-linkages through multivalent metal ions.
Hayaka Fukuzumi - One of the best experts on this subject based on the ideXlab platform.
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pore size determination of tempo oxidized cellulose nanofibril films by positron annihilation lifetime spectroscopy
Biomacromolecules, 2011Co-Authors: Hayaka Fukuzumi, Tsuguyuki Saito, Shinichiro Iwamoto, Yoshiaki Kumamoto, T Ohdaira, Ryoichi Suzuki, Akira IsogaiAbstract:Wood cellulose nanofibril films with Sodium Carboxylate groups prepared from a 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized pulp exhibited an extremely low oxygen permeability of 0.0008 mL μm m–2 day–1 kPa–1 at 0% relative humidity (RH). Positron annihilation lifetime spectroscopy (PALS) was used to determine the pore sizes in wood and tunicate TEMPO-oxidized cellulose nanofibril (TOCN-COONa) films in a vacuum (i.e., at 0% RH). PALS analysis revealed that the pore size of the wood TOCN-COONa films remained nearly at 0.47 nm from the film surface to the interior of the film. This is probably the cause of this high oxygen-barrier properties at 0% RH. The crystalline structure of TOCN-COONa also contributes to the high oxygen-barrier properties of the wood TOCN-COONa films. However, the oxygen permeability of the wood TOCN-COONa films increased to 0.17 mL μm m–2 day–1 kPa–1 at 50% RH, which is one of the shortcomings of hydrophilic TOCN-COONa films.
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pore size determination of tempo oxidized cellulose nanofibril films by positron annihilation lifetime spectroscopy
Biomacromolecules, 2011Co-Authors: Hayaka Fukuzumi, Tsuguyuki Saito, Shinichiro Iwamoto, Yoshiaki Kumamoto, T Ohdaira, Ryoichi Suzuki, Akira IsogaiAbstract:Wood cellulose nanofibril films with Sodium Carboxylate groups prepared from a 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized pulp exhibited an extremely low oxygen permeability of 0.0008 mL μm m–2 day–1 kPa–1 at 0% relative humidity (RH). Positron annihilation lifetime spectroscopy (PALS) was used to determine the pore sizes in wood and tunicate TEMPO-oxidized cellulose nanofibril (TOCN-COONa) films in a vacuum (i.e., at 0% RH). PALS analysis revealed that the pore size of the wood TOCN-COONa films remained nearly at 0.47 nm from the film surface to the interior of the film. This is probably the cause of this high oxygen-barrier properties at 0% RH. The crystalline structure of TOCN-COONa also contributes to the high oxygen-barrier properties of the wood TOCN-COONa films. However, the oxygen permeability of the wood TOCN-COONa films increased to 0.17 mL μm m–2 day–1 kPa–1 at 50% RH, which is one of the shortcomings of hydrophilic TOCN-COONa films.
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preparation and characterization of tempo oxidized cellulose nanofibril films with free carboxyl groups
Carbohydrate Polymers, 2011Co-Authors: Shuji Fujisawa, Yusuke Okita, Hayaka Fukuzumi, Tsuguyuki Saito, Akira IsogaiAbstract:Abstract A 2,2,6,6-tetramehylpiperidine-1-oxy radical (TEMPO)-oxidized wood cellulose with Sodium Carboxylate groups was completely converted to individual TEMPO-oxidized cellulose nanofibrils with free carboxyl groups (TOCN-COOH) dispersed in water at pH 4.6. Self-standing films prepared by casting and drying of the TOCN-COOH/water dispersion were flexible and highly transparent. Fourier transform infrared (FT-IR) spectra and Sodium content determination confirmed that the Sodium Carboxylate groups of TOCN-COONa were almost completely converted to free carboxyl groups in TOCN-COOH. The TOCN-COOH and TOCN-COONa films had similar densities and tensile strengths, but the former had lower moisture content, higher Young's modulus and lower elongation values than those of the latter. The oxygen permeability of the TOCN-COOH films was 0.049 mL μm m −2 day −1 kPa −1 , which was clearly lower than that (15.5 mL μm m −2 day −1 kPa −1 ) of poly(ethylene terephthalate) films.
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thermal stabilization of tempo oxidized cellulose
Polymer Degradation and Stability, 2010Co-Authors: Hayaka Fukuzumi, Yusuke Okita, Tsuguyuki Saito, Akira IsogaiAbstract:Abstract A partially C6-Carboxylated cellulose with Carboxylate content of 1.68 mmol/g was prepared by 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO)-mediated oxidation of a softwood bleached kraft pulp. Thermogravimetric analyses of the TEMPO-oxidized cellulose (TOC) and its related materials were studied to improve thermal stability of the TOC. Thermal decomposition (T d ) points of the TOC with Sodium Carboxylate groups, alkali-treated TOC with free carboxyl groups of 0.23 mmol/g and the original cellulose were 222 °C, 264 °C and 275 °C, respectively. Thus, the anhydroglucuronic acid units formed by TEMPO-mediated oxidation of the native wood cellulose and present in the TOC cause the decrease in T d point by decarbonation during heating process. When carboxyl groups in the TOC were methylated with trimethylsilyl diazomethane (TMSCHN 2 ), the T d point increased from 222 °C to 249 °C, and the peak temperature in its derivative thermogravimetric (DTG) curve increased from 273 °C to 313 °C, which was almost equal to that of the original cellulose. Thus, the methyl esterification of carboxyl groups in the TOC is effective in improving thermal stability. When Sodium ions present in the TOC as counter ions of Carboxylate groups were exchanged to some other metal ions, thermal stability was improved to some extent. Especially, when CaCl 2 , Ca(OAc) 2 , Ca(NO 3 ) 2 and CaI 2 solutions were used in the ion-exchange treatments, the peak temperatures in the DTG curves increased to approximately 300 °C. MgCl 2 , NiCl 2 , SrCl 2 and Sr(OAc) 2 solutions were also effective to some extent in increasing the peak temperatures of DTG curves. Thus, thermal stability of the fibrous TOC can be improved to some extent by methyl esterification of the Sodium Carboxylate groups present in the original TOC with TMSCHN 2 or ion-exchange treatments with some metal salt solutions.
Tsuguyuki Saito - One of the best experts on this subject based on the ideXlab platform.
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Luminescent and Transparent Nanocellulose Films Containing Europium Carboxylate Groups as Flexible Dielectric Materials
2018Co-Authors: Quanling Yang, Tsuguyuki Saito, Chenggang Zhang, Zhuqun Shi, Jinyu Wang, Chuanxi Xiong, Akira IsogaiAbstract:Transparent, flexible, and luminescent 2,2,6,6-tetramethylpiperidine-1-oxyl radical-oxidized cellulose nanofibril films with europium Carboxylate groups (TOCN-Eu) are proposed as potential flexible dielectric materials. The TOCN-Eu films were prepared from TOCN films with Sodium Carboxylate groups (TOCN-Na) by immersion in Eu(NO3)3 solution and subsequent washing with water and drying of the wet TOCN-Eu hydrogel films. The nanolayered TOCN-Eu films emit red light under ultraviolet-light irradiation and exhibit greatly improved dry and wet mechanical properties, water resistance, thermal stability, oxygen-barrier properties, dielectric breakdown strength, and energy density than conventional TOCN-Na films. These characteristic properties of the TOCN-Eu films are most likely caused by the formation of strong ionic bonds between the Carboxylate groups and Eu3+ ions. These high-performance cellulose nanofibril films are promising for application as multifunctional materials in light-emitting, photovoltaic, and energy storage devices
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water resistant and high oxygen barrier nanocellulose films with interfibrillar cross linkages formed through multivalent metal ions
Journal of Membrane Science, 2016Co-Authors: Michiko Shimizu, Tsuguyuki Saito, Akira IsogaiAbstract:Abstract Once-dried 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized cellulose nanofibril (TOCN) films with Sodium Carboxylate groups (TOCN–COONa) were soaked in aqueous MgCl2, CaCl2, AlCl3 and FeCl3 solutions to change the counterion to TOCNs–COOM films (M: metal ion). Dry TOCN–COOM films had high Young's moduli (11–20 GPa) and tensile strength (170–280 MPa). In particular, the wet TOCN films with aluminum and iron (III) Carboxylates had high Young's moduli and tensile strengths of ~3 GPa and 30–40 MPa, respectively, even at water contents of ~470%. Moreover, the dry TOCN films with calcium and aluminum Carboxylates had extremely low oxygen permeabilities of 0.08 and 0.15 mL µm m−2 day−1 kPa−1, respectively, even at 80% relative humidity, which are outstanding values compared to those of other films reported previously. These results are explained in terms of the high water resistance of the films, which is caused by the formation of interfibrillar cross-linkages through multivalent metal ions.
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pore size determination of tempo oxidized cellulose nanofibril films by positron annihilation lifetime spectroscopy
Biomacromolecules, 2011Co-Authors: Hayaka Fukuzumi, Tsuguyuki Saito, Shinichiro Iwamoto, Yoshiaki Kumamoto, T Ohdaira, Ryoichi Suzuki, Akira IsogaiAbstract:Wood cellulose nanofibril films with Sodium Carboxylate groups prepared from a 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized pulp exhibited an extremely low oxygen permeability of 0.0008 mL μm m–2 day–1 kPa–1 at 0% relative humidity (RH). Positron annihilation lifetime spectroscopy (PALS) was used to determine the pore sizes in wood and tunicate TEMPO-oxidized cellulose nanofibril (TOCN-COONa) films in a vacuum (i.e., at 0% RH). PALS analysis revealed that the pore size of the wood TOCN-COONa films remained nearly at 0.47 nm from the film surface to the interior of the film. This is probably the cause of this high oxygen-barrier properties at 0% RH. The crystalline structure of TOCN-COONa also contributes to the high oxygen-barrier properties of the wood TOCN-COONa films. However, the oxygen permeability of the wood TOCN-COONa films increased to 0.17 mL μm m–2 day–1 kPa–1 at 50% RH, which is one of the shortcomings of hydrophilic TOCN-COONa films.
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pore size determination of tempo oxidized cellulose nanofibril films by positron annihilation lifetime spectroscopy
Biomacromolecules, 2011Co-Authors: Hayaka Fukuzumi, Tsuguyuki Saito, Shinichiro Iwamoto, Yoshiaki Kumamoto, T Ohdaira, Ryoichi Suzuki, Akira IsogaiAbstract:Wood cellulose nanofibril films with Sodium Carboxylate groups prepared from a 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized pulp exhibited an extremely low oxygen permeability of 0.0008 mL μm m–2 day–1 kPa–1 at 0% relative humidity (RH). Positron annihilation lifetime spectroscopy (PALS) was used to determine the pore sizes in wood and tunicate TEMPO-oxidized cellulose nanofibril (TOCN-COONa) films in a vacuum (i.e., at 0% RH). PALS analysis revealed that the pore size of the wood TOCN-COONa films remained nearly at 0.47 nm from the film surface to the interior of the film. This is probably the cause of this high oxygen-barrier properties at 0% RH. The crystalline structure of TOCN-COONa also contributes to the high oxygen-barrier properties of the wood TOCN-COONa films. However, the oxygen permeability of the wood TOCN-COONa films increased to 0.17 mL μm m–2 day–1 kPa–1 at 50% RH, which is one of the shortcomings of hydrophilic TOCN-COONa films.
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preparation and characterization of tempo oxidized cellulose nanofibril films with free carboxyl groups
Carbohydrate Polymers, 2011Co-Authors: Shuji Fujisawa, Yusuke Okita, Hayaka Fukuzumi, Tsuguyuki Saito, Akira IsogaiAbstract:Abstract A 2,2,6,6-tetramehylpiperidine-1-oxy radical (TEMPO)-oxidized wood cellulose with Sodium Carboxylate groups was completely converted to individual TEMPO-oxidized cellulose nanofibrils with free carboxyl groups (TOCN-COOH) dispersed in water at pH 4.6. Self-standing films prepared by casting and drying of the TOCN-COOH/water dispersion were flexible and highly transparent. Fourier transform infrared (FT-IR) spectra and Sodium content determination confirmed that the Sodium Carboxylate groups of TOCN-COONa were almost completely converted to free carboxyl groups in TOCN-COOH. The TOCN-COOH and TOCN-COONa films had similar densities and tensile strengths, but the former had lower moisture content, higher Young's modulus and lower elongation values than those of the latter. The oxygen permeability of the TOCN-COOH films was 0.049 mL μm m −2 day −1 kPa −1 , which was clearly lower than that (15.5 mL μm m −2 day −1 kPa −1 ) of poly(ethylene terephthalate) films.
Zhi Yong Yang - One of the best experts on this subject based on the ideXlab platform.
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high blades spreadability of chlorpyrifos microcapsules prepared with polysiloxane Sodium Carboxylate Sodium carboxymethylcellulose gelatin via complex coacervation
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2017Co-Authors: Run Ying Dai, Sheng Yong You, Qian Liu, Ling Wei, Xi Gen Huang, Zhi Yong YangAbstract:Abstract The sustainable-release property and spreadability of microencapsulated pesticide on blades have attracted special interest mainly because they are related to the utilization of pesticide. In this work, polysiloxane Sodium Carboxylate (PSiSC) surfactant with double hydrophobic chains has been introduced for the first time into the capsule shell materials to improve the spreadability of the chlorpyrifos microcapsules on rice blades. The silicone chlorpyrifos microcapsules have been prepared with PSiSC/gelatin (GE)/Sodium carboxymethylcellulose (NaCMC) by complex coacervation method. Optical microscopy, scanning electron microscopy, laser particle size analyzer, fourier-transform infrared, energy dispersive X-ray spectroscopy, contact angle measurement and UV/VIS spectrometer are used to characterize the silicone chlorpyrifos microcapsules. The PSiSC/NaCMC/GE microcapsules that exhibit the chlorpyrifos encapsulation rate of 50.8%, surface smooth, the mean diameter around 3.5 μm and shell thickness of 285 nm, fabricated with 1.2 mmol/L PSiSC surfactant at pH 4.6. The chlorpyrifos-loaded microcapsules are of remarkable sustainable-release property. The PSiSC/NaCMC/GE microcapsules own high spreadability on the rice blades, which promotes increasing the residual amount of chlorpyrifos microcapsules on hydrophobic blades, thereby improving the utilization of chlorpyrifos.
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High blades spreadability of chlorpyrifos microcapsules prepared with polysiloxane Sodium Carboxylate/Sodium carboxymethylcellulose/gelatin via complex coacervation
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2017Co-Authors: Run Ying Dai, Sheng Yong You, Qian Liu, Ling Wei, Xi Gen Huang, Zhi Yong YangAbstract:Abstract The sustainable-release property and spreadability of microencapsulated pesticide on blades have attracted special interest mainly because they are related to the utilization of pesticide. In this work, polysiloxane Sodium Carboxylate (PSiSC) surfactant with double hydrophobic chains has been introduced for the first time into the capsule shell materials to improve the spreadability of the chlorpyrifos microcapsules on rice blades. The silicone chlorpyrifos microcapsules have been prepared with PSiSC/gelatin (GE)/Sodium carboxymethylcellulose (NaCMC) by complex coacervation method. Optical microscopy, scanning electron microscopy, laser particle size analyzer, fourier-transform infrared, energy dispersive X-ray spectroscopy, contact angle measurement and UV/VIS spectrometer are used to characterize the silicone chlorpyrifos microcapsules. The PSiSC/NaCMC/GE microcapsules that exhibit the chlorpyrifos encapsulation rate of 50.8%, surface smooth, the mean diameter around 3.5 μm and shell thickness of 285 nm, fabricated with 1.2 mmol/L PSiSC surfactant at pH 4.6. The chlorpyrifos-loaded microcapsules are of remarkable sustainable-release property. The PSiSC/NaCMC/GE microcapsules own high spreadability on the rice blades, which promotes increasing the residual amount of chlorpyrifos microcapsules on hydrophobic blades, thereby improving the utilization of chlorpyrifos.
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High blades spreadability of chlorpyrifos microcapsules prepared with polysiloxane Sodium Carboxylate/Sodium carboxymethylcellulose/gelatin via complex coacervation A Physicochemical and engineering aspects
Colloids and Surfaces, 2017Co-Authors: Run Ying Dai, Sheng Yong You, Qian Liu, Ling Wei, Xi Gen Huang, Lu Limin, Zhi Yong YangAbstract:The sustainable-release property and spreadability of microencapsulated pesticide on blades have attracted special interest mainly because they are related to the utilization of pesticide. In this work, polysiloxane Sodium Carboxylate (PSiSC) surfactant with double hydrophobic chains has been introduced for the first time into the capsule shell materials to improve the spreadability of the chlorpyrifos microcapsules on rice blades. The silicone chlorpyrifos microcapsules have been prepared with PSiSC/gelatin (GE)/Sodium carboxymethylcellulose (NaCMC) by complex coacervation method. Optical microscopy, scanning electron microscopy, laser particle size analyzer, fourier-transform infrared, energy dispersive X-ray spectroscopy, contact angle measurement and UV/VIS spectrometer are used to characterize the silicone chlorpyrifos microcapsules. The PSiSC/NaCMC/GE microcapsules that exhibit the chlorpyrifos encapsulation rate of 50.8%, surface smooth, the mean diameter around 3.5μm and shell thickness of 285nm, fabricated with 1.2mmol/L PSiSC surfactant at pH 4.6. The chlorpyrifos-loaded microcapsules are of remarkable sustainable-release property. The PSiSC/NaCMC/GE microcapsules own high spreadability on the rice blades, which promotes increasing the residual amount of chlorpyrifos microcapsules on hydrophobic blades, thereby improving the utilization of chlorpyrifos.
Run Ying Dai - One of the best experts on this subject based on the ideXlab platform.
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high blades spreadability of chlorpyrifos microcapsules prepared with polysiloxane Sodium Carboxylate Sodium carboxymethylcellulose gelatin via complex coacervation
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2017Co-Authors: Run Ying Dai, Sheng Yong You, Qian Liu, Ling Wei, Xi Gen Huang, Zhi Yong YangAbstract:Abstract The sustainable-release property and spreadability of microencapsulated pesticide on blades have attracted special interest mainly because they are related to the utilization of pesticide. In this work, polysiloxane Sodium Carboxylate (PSiSC) surfactant with double hydrophobic chains has been introduced for the first time into the capsule shell materials to improve the spreadability of the chlorpyrifos microcapsules on rice blades. The silicone chlorpyrifos microcapsules have been prepared with PSiSC/gelatin (GE)/Sodium carboxymethylcellulose (NaCMC) by complex coacervation method. Optical microscopy, scanning electron microscopy, laser particle size analyzer, fourier-transform infrared, energy dispersive X-ray spectroscopy, contact angle measurement and UV/VIS spectrometer are used to characterize the silicone chlorpyrifos microcapsules. The PSiSC/NaCMC/GE microcapsules that exhibit the chlorpyrifos encapsulation rate of 50.8%, surface smooth, the mean diameter around 3.5 μm and shell thickness of 285 nm, fabricated with 1.2 mmol/L PSiSC surfactant at pH 4.6. The chlorpyrifos-loaded microcapsules are of remarkable sustainable-release property. The PSiSC/NaCMC/GE microcapsules own high spreadability on the rice blades, which promotes increasing the residual amount of chlorpyrifos microcapsules on hydrophobic blades, thereby improving the utilization of chlorpyrifos.
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High blades spreadability of chlorpyrifos microcapsules prepared with polysiloxane Sodium Carboxylate/Sodium carboxymethylcellulose/gelatin via complex coacervation
Colloids and Surfaces A: Physicochemical and Engineering Aspects, 2017Co-Authors: Run Ying Dai, Sheng Yong You, Qian Liu, Ling Wei, Xi Gen Huang, Zhi Yong YangAbstract:Abstract The sustainable-release property and spreadability of microencapsulated pesticide on blades have attracted special interest mainly because they are related to the utilization of pesticide. In this work, polysiloxane Sodium Carboxylate (PSiSC) surfactant with double hydrophobic chains has been introduced for the first time into the capsule shell materials to improve the spreadability of the chlorpyrifos microcapsules on rice blades. The silicone chlorpyrifos microcapsules have been prepared with PSiSC/gelatin (GE)/Sodium carboxymethylcellulose (NaCMC) by complex coacervation method. Optical microscopy, scanning electron microscopy, laser particle size analyzer, fourier-transform infrared, energy dispersive X-ray spectroscopy, contact angle measurement and UV/VIS spectrometer are used to characterize the silicone chlorpyrifos microcapsules. The PSiSC/NaCMC/GE microcapsules that exhibit the chlorpyrifos encapsulation rate of 50.8%, surface smooth, the mean diameter around 3.5 μm and shell thickness of 285 nm, fabricated with 1.2 mmol/L PSiSC surfactant at pH 4.6. The chlorpyrifos-loaded microcapsules are of remarkable sustainable-release property. The PSiSC/NaCMC/GE microcapsules own high spreadability on the rice blades, which promotes increasing the residual amount of chlorpyrifos microcapsules on hydrophobic blades, thereby improving the utilization of chlorpyrifos.
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High blades spreadability of chlorpyrifos microcapsules prepared with polysiloxane Sodium Carboxylate/Sodium carboxymethylcellulose/gelatin via complex coacervation A Physicochemical and engineering aspects
Colloids and Surfaces, 2017Co-Authors: Run Ying Dai, Sheng Yong You, Qian Liu, Ling Wei, Xi Gen Huang, Lu Limin, Zhi Yong YangAbstract:The sustainable-release property and spreadability of microencapsulated pesticide on blades have attracted special interest mainly because they are related to the utilization of pesticide. In this work, polysiloxane Sodium Carboxylate (PSiSC) surfactant with double hydrophobic chains has been introduced for the first time into the capsule shell materials to improve the spreadability of the chlorpyrifos microcapsules on rice blades. The silicone chlorpyrifos microcapsules have been prepared with PSiSC/gelatin (GE)/Sodium carboxymethylcellulose (NaCMC) by complex coacervation method. Optical microscopy, scanning electron microscopy, laser particle size analyzer, fourier-transform infrared, energy dispersive X-ray spectroscopy, contact angle measurement and UV/VIS spectrometer are used to characterize the silicone chlorpyrifos microcapsules. The PSiSC/NaCMC/GE microcapsules that exhibit the chlorpyrifos encapsulation rate of 50.8%, surface smooth, the mean diameter around 3.5μm and shell thickness of 285nm, fabricated with 1.2mmol/L PSiSC surfactant at pH 4.6. The chlorpyrifos-loaded microcapsules are of remarkable sustainable-release property. The PSiSC/NaCMC/GE microcapsules own high spreadability on the rice blades, which promotes increasing the residual amount of chlorpyrifos microcapsules on hydrophobic blades, thereby improving the utilization of chlorpyrifos.
