start-ver=1.4 cd-journal=joma no-vol= cd-vols= no-issue= article-no= start-page= end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2024 dt-pub=20240405 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Engineering Interconnected Open-Porous Particles via Microfluidics Using Bijel Droplets as Structural Templates en-subtitle= kn-subtitle= en-abstract= kn-abstract=Designing porous structures is key in materials science, particularly for separation, catalysis, and cell culture systems. Bicontinuous interfacially jammed emulsion gels represent a unique class of soft matter formed by kinetically arresting the separation of the spinodal decomposition phase, which is stabilized by colloidal particles with neutral wetting. This study introduces a microfluidic technique to create highly interconnected open-porous particles using bijel droplets stabilized with hexadecyltrimethylammonium bromide (CTAB)-modified silica particles. Monodisperse droplets comprising a hydrophobic monomer, water, ethanol, silica particles, and CTAB were initially formed in the microfluidic device. The diffusion of ethanol from these droplets into the continuous cyclohexane phase triggered spinodal decomposition within the droplets. The phase-separated structure within the droplets was stabilized by the CTAB-modified silica particles, and subsequent photopolymerization yielded microparticles with highly interconnected, open pores. Moreover, the influence of the ratio of the CTAB and silica particles, fluid composition, and microchannel direction on the final structure of the microparticles was explored. Our findings indicated that the phase-separated structure of the particles transitioned from oil-in-water to water-in-oil as the CTAB/silica ratio was increased. At intermediate CTAB/silica ratios, microparticles with bicontinuous structures were formed. Regardless of the fluid composition, the pore size of the particles increased with time after phase separation. However, this coarsening was arrested 15 s after droplet formation in the CTAB-modified silica particles, accompanied by a change in the particle shape from spherical to ellipsoidal. In situ observations of the bijel droplet formation revealed that the particle shape deformation is caused by the rolling of elastic bijel droplets at the bottom of the microchannel. As such, the channel setup was altered from horizontal to vertical to prevent the deformation of bijel droplets, resulting in spherical particles with open pores. en-copyright= kn-copyright= en-aut-name=MasaokaMina en-aut-sei=Masaoka en-aut-mei=Mina kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=IshidaHiroaki en-aut-sei=Ishida en-aut-mei=Hiroaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=WatanabeTakaichi en-aut-sei=Watanabe en-aut-mei=Takaichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=OnoTsutomu en-aut-sei=Ono en-aut-mei=Tsutomu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= affil-num=1 en-affil=Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=2 en-affil=Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=3 en-affil=Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=4 en-affil=Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University kn-affil= END start-ver=1.4 cd-journal=joma no-vol=20 cd-vols= no-issue=7 article-no= start-page=1611 end-page=1619 dt-received= dt-revised= dt-accepted= dt-pub-year=2024 dt-pub=20240118 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Controlled mechanical properties of poly(ionic liquid)-based hydrophobic ion gels by the introduction of alumina nanoparticles with different shapes en-subtitle= kn-subtitle= en-abstract= kn-abstract=Ionic–liquid gels, also known as ion gels, have gained considerable attention due to their high ionic conductivity and CO2 absorption capacity. However, their low mechanical strength has hindered their practical applications. A potential solution to this challenge is the incorporation of particles, such as silica nanoparticles, TiO2 nanoparticles, and metal–organic frameworks (MOFs) into ion gels. Comparative studies on the effect of particles with different shapes are still in progress. This study investigated the effect of the shape of particles introduced into ion gels on their mechanical properties. Consequently, alumina/poly(ionic liquid) (PIL) double-network (DN) ion gels consisting of clustered alumina nanoparticles with various shapes (either spherical or rod-shaped) and a chemically crosslinked poly[1-ethyl-3-vinylimidazolium bis(trifluoromethanesulfonyl)imide] (PC2im-TFSI, PIL) network were prepared. The results revealed that the mechanical strengths of the alumina/PIL DN ion gels were superior to those of PIL single-network ion gels without particles. Notably, the fracture energies of the rod-shaped alumina/PIL DN ion gels were approximately 2.6 times higher than those of the spherical alumina/PIL DN ion gels. Cyclic tensile tests were performed, and the results indicate that the loading energy on the ion gel was dissipated through the fracture of the alumina network. TEM observation suggests that the variation in the mechanical strength depending on the shape can be attributed to differences in the aggregation structure of the alumina particles, thus indicating the possibility of tuning the mechanical strength of ion gels by altering not only particle kinds but its shape. en-copyright= kn-copyright= en-aut-name=MizutaniYuna en-aut-sei=Mizutani en-aut-mei=Yuna kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=WatanabeTakaichi en-aut-sei=Watanabe en-aut-mei=Takaichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=LopezCarlos G. en-aut-sei=Lopez en-aut-mei=Carlos G. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=OnoTsutomu en-aut-sei=Ono en-aut-mei=Tsutomu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= affil-num=1 en-affil=Department of Applied Chemistry, Graduate School of Natural Science, Okayama University kn-affil= affil-num=2 en-affil=Department of Applied Chemistry, Graduate School of Natural Science, Okayama University kn-affil= affil-num=3 en-affil=Department of Materials Science and Engineering, The Pennsylvania State University kn-affil= affil-num=4 en-affil=Department of Applied Chemistry, Graduate School of Natural Science, Okayama University kn-affil= END start-ver=1.4 cd-journal=joma no-vol=19 cd-vols= no-issue=15 article-no= start-page=2745 end-page=2754 dt-received= dt-revised= dt-accepted= dt-pub-year=2023 dt-pub=20230323 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Toughening of poly(ionic liquid)-based ion gels with cellulose nanofibers as a sacrificial network en-subtitle= kn-subtitle= en-abstract= kn-abstract=Ion gels have the potential to be used in a broad range of applications, such as in carbon dioxide separation membranes and soft electronics. However, their low mechanical strength limits their practical applications. In this study, we developed double-network (DN) ion gels composed of TEMPO-oxidized cellulose nanofibers with hydrophobic groups (TOCNF) and cross-linked poly[1-ethyl-3-vinylimidazolium bis(trifluoromethanesulfonyl)imide] (PC2im-TFSI) networks. The mechanical strength of the gel increased as the amount of TOCNF in the gels increased up to 6 wt%. Moreover, the fracture energy of the DN ion gels with 6 wt% TOCNF was found to be 19 times higher than that of the PC2im-TFSI single network (SN) ion gels. Cyclic stress-strain measurements of the DN gels showed that the loading energy on the gels dissipates owing to the destruction of the physically cross-linked TOCNF network in the gels. The DN ion gels also exhibited a high decomposition temperature of approximately 400 degrees C because of the thermal stability of all components. Additionally, the fracture energy of the TOCNF/poly(ionic liquid) (PIL) DN ion gel was two times higher than that of the silica nanoparticles/PIL DN ion gel developed in our previous study [Watanabe et al., Soft Matter, 2020, 16, 1572-1581]. This suggests that fiber-shaped nanomaterials are more effective than spherical nanomaterials in enhancing the mechanical properties of ion gels. These results show that TOCNF can be used to toughen PIL-based ion gels and hence broaden their applications. en-copyright= kn-copyright= en-aut-name=WatanabeTakaichi en-aut-sei=Watanabe en-aut-mei=Takaichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=OeEmiho en-aut-sei=Oe en-aut-mei=Emiho kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=MizutaniYuna en-aut-sei=Mizutani en-aut-mei=Yuna kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=OnoTsutomu en-aut-sei=Ono en-aut-mei=Tsutomu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= affil-num=1 en-affil=Department of Applied Chemistry, Graduate School of Natural Science, Okayama University kn-affil= affil-num=2 en-affil=Department of Applied Chemistry, Graduate School of Natural Science, Okayama University kn-affil= affil-num=3 en-affil=Department of Applied Chemistry, Graduate School of Natural Science, Okayama University kn-affil= affil-num=4 en-affil=Department of Applied Chemistry, Graduate School of Natural Science, Okayama University kn-affil= END start-ver=1.4 cd-journal=joma no-vol=2 cd-vols= no-issue=3 article-no= start-page=250 end-page=259 dt-received= dt-revised= dt-accepted= dt-pub-year=2022 dt-pub=20220126 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Microfluidic Production of Monodisperse Biopolymer Microcapsules for Latent Heat Storage en-subtitle= kn-subtitle= en-abstract= kn-abstract=Microencapsulation of phase change materials in a polymer shell is a promising technology to prevent them from leakage and to use them as a handleable powder state. However, the microencapsulation process is a time-consuming process because the typical shell-forming step requires polymerization or evaporation of the solvent. In this study, we report a simple and rapid flow process to prepare monodisperse biocompatible cellulose acetate (CA) microcapsules encapsulating n-hexadecane (HD) for latent heat storage applications. The microcapsules were prepared by combining microfluidic droplet formation and subsequent rapid solvent removal from the droplets by solvent diffusion. The diameter and shell thickness of the microcapsules could be controlled by adjusting the flow rate and the HD-to-CA weight ratio in the dispersed phase. We found that 1-hexadecanol added to the microcapsules played the role of a nucleation agent and mitigated the supercooling phenomenon during crystallization. Furthermore, cross-linking of the CA shell with poly(propylene glycol), tolylene 2,4-diisocyanate terminated, resulted in the formation of a thin and dense shell. The microcapsules exhibited a 66 wt % encapsulation efficiency and a 176 J g–1 latent heat storage capacity, with negligible supercooling. We believe that this microflow process can contribute to the preparation of environmentally friendly microcapsules for heat storage applications. en-copyright= kn-copyright= en-aut-name=WatanabeTakaichi en-aut-sei=Watanabe en-aut-mei=Takaichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=SakaiYuko en-aut-sei=Sakai en-aut-mei=Yuko kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=SugimoriNaomi en-aut-sei=Sugimori en-aut-mei=Naomi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=IkedaToshinori en-aut-sei=Ikeda en-aut-mei=Toshinori kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=MonzenMasayuki en-aut-sei=Monzen en-aut-mei=Masayuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=OnoTsutomu en-aut-sei=Ono en-aut-mei=Tsutomu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= affil-num=1 en-affil=Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=2 en-affil=Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=3 en-affil=Chusei Oil Co., Ltd. kn-affil= affil-num=4 en-affil=Chusei Oil Co., Ltd. kn-affil= affil-num=5 en-affil=Chusei Oil Co., Ltd. kn-affil= affil-num=6 en-affil=Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University kn-affil= en-keyword=microfluidics kn-keyword=microfluidics en-keyword=phase separation kn-keyword=phase separation en-keyword=core−shell kn-keyword=core−shell en-keyword=cellulose acetate kn-keyword=cellulose acetate en-keyword=latent heat storage kn-keyword=latent heat storage END start-ver=1.4 cd-journal=joma no-vol=4 cd-vols= no-issue=1 article-no= start-page=348 end-page=356 dt-received= dt-revised= dt-accepted= dt-pub-year=2021 dt-pub=20211222 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Multilayer Poly(ionic liquid) Microcapsules Prepared by Sequential Phase Separation and Subsequent Photopolymerization in Ternary Emulsion Droplets en-subtitle= kn-subtitle= en-abstract= kn-abstract=We report a simple microfluidic process to prepare multilayer poly(ionic liquid)s (PILs) microcapsules via sequential liquid-liquid phase separation within ternary emulsion droplets followed by the photopolymerization of ionic liquid (IL) monomerrich phases. The emulsion droplets, consisting of a hydrophobic IL monomer, water, and　N,N-dimethylformamide (DMF) are first formed in a microfluidic device, and the droplets are then carried by a continuous aqueous phase. Subsequently, DMF diffuses from the droplets into the continuous aqueous phase, resulting in the sequential internal phase separation of the IL-rich and water-rich phases, generating multilayer emulsion droplets comprising alternating IL-rich and water-rich phases. The number of droplet layers was controlled from one to five by varying the initial composition of the dispersed phase. Furthermore, in the conditions where higher-order emulsion droplets were formed, the time scale between the onset of phase separation and the formation of each layer became shorter. Additionally, the IL-rich phases in the multilayer emulsion droplets were easily solidified via photopolymerization, resulting in PILs microcapsules with multilayer structures. Anion exchange of the obtained PILs microcapsules effectuated their transition from a hydrophobic to a hydrophilic nature, resulting in PILs microcapsules with diverse swelling properties and PILs layers permeability across various solvents. We believe that the sequential phase separation system observed in the ternary emulsion droplets can pave the way for the design of PILs-based colloidal materials with thermodynamically non-equilibrium structures, thereby extending their application in functional materials. en-copyright= kn-copyright= en-aut-name=WatanabeTakaichi en-aut-sei=Watanabe en-aut-mei=Takaichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=YasuharaYuka en-aut-sei=Yasuhara en-aut-mei=Yuka kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=OnoTsutomu en-aut-sei=Ono en-aut-mei=Tsutomu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= affil-num=1 en-affil=Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1, Tsushima-naka, Kita-ku, Okayama 700-8530, Japan kn-affil= affil-num=2 en-affil=Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1, Tsushima-naka, Kita-ku, Okayama 700-8530, Japan kn-affil= affil-num=3 en-affil=Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University, 3-1-1, Tsushima-naka, Kita-ku, Okayama 700-8530, Japan kn-affil= en-keyword=Microfluidics kn-keyword=Microfluidics en-keyword=Multiple emulsion kn-keyword=Multiple emulsion en-keyword=Poly(ionic liquid) kn-keyword=Poly(ionic liquid) en-keyword=Phase separation kn-keyword=Phase separation en-keyword=Non-equilibrium structure kn-keyword=Non-equilibrium structure END start-ver=1.4 cd-journal=joma no-vol=6 cd-vols= no-issue=15 article-no= start-page=10030 end-page=10038 dt-received= dt-revised= dt-accepted= dt-pub-year=2021 dt-pub=20210409 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Design of Clickable Ionic Liquid Monomers to Enhance Ionic Conductivity for Main-Chain 1,2,3-Triazolium-Based Poly(Ionic Liquid)s en-subtitle= kn-subtitle= en-abstract= kn-abstract=A series of clickable alpha-azide-omega-alkyne ionic liquid (IL) monomers with an ethylene oxide spacer were developed and applied to the synthesis of 1,2,3-triazolium-based poly(ionic liquid)s (TPILs) with high ionic conductivities via one-step thermal azide-alkyne cycloaddition click chemistry. Subsequently, the number of IL moieties in the resultant TPILs was further increased by N-alkylation of the 1,2,3-triazole-based backbones of the TPILs with a quarternizing reagent. This strategy affords the preparation of TPILs having either one or two 1,2,3-triazolium cations with bis(trifluoromethylsulfonyl)imide anions in a monomer unit. Synthesis of the TPILs was confirmed by H-1 and C-13 NMR spectroscopy and gel permeation chromatography. The effects of the length of the ethylene oxide spacer and the number of IL moieties in the IL monomer unit on the physicochemical properties of the TPILs were characterized by differential scanning calorimetry, thermogravimetric analysis, and impedance spectroscopy. The introduction of a longer ethylene oxide spacer or an increase in the number of IL moieties in the monomer unit resulted in TPILs with lower glass-transition temperatures and higher ionic conductivities. The highest ionic conductivity achieved in this study was 2.0 x 10(-5) S cm(-1) at 30 degrees C. These results suggest that the design of the IL monomer provides the resultant polymer with high chain flexibility and a high IL density, and so it is effective for preparing TPILs with high ionic conductivities. en-copyright= kn-copyright= en-aut-name=HiraiRuka en-aut-sei=Hirai en-aut-mei=Ruka kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=WatanabeTakaichi en-aut-sei=Watanabe en-aut-mei=Takaichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=OnoTsutomu en-aut-sei=Ono en-aut-mei=Tsutomu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= affil-num=1 en-affil=Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=2 en-affil=Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=3 en-affil=Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University kn-affil= END start-ver=1.4 cd-journal=joma no-vol=10 cd-vols= no-issue=62 article-no= start-page=37743 end-page=37748 dt-received= dt-revised= dt-accepted= dt-pub-year=2020 dt-pub=20201013 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=One-pot synthesis of poly(ionic liquid)s with 1,2,3-triazolium-based backbones via clickable ionic liquid monomers en-subtitle= kn-subtitle= en-abstract= kn-abstract=Clickable α-azide-ω-alkyne ionic liquid monomers were developed and subsequently applied to the one-pot synthesis of ionically conducting poly(ionic liquid)s with 1,2,3-triazolium-based backbones through a click chemistry strategy. This approach does not require the use of solvents, polymerisation mediators, or catalysts. The obtained poly(ionic liquid)s were characterized by NMR, differential scanning calorimetry, thermogravimetric analysis, and impedance spectroscopy analysis. Moreover, these poly(ionic liquid)s were cross-linked via N-alkylation with a dianion quarternizing agent to achieve enhanced ionic conductivity and mechanical strength. The resulting free-standing films showed a Young's modulus up to 4.8 MPa and ionic conductivities up to 4.60 × 10−8 S cm−1 at 30 °C. This facile synthetic strategy has the potential to expand the availability of poly(ionic liquid)s and promote the development of functional materials. en-copyright= kn-copyright= en-aut-name=HiraiRuka en-aut-sei=Hirai en-aut-mei=Ruka kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=HibinoTatsuki en-aut-sei=Hibino en-aut-mei=Tatsuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=WatanabeTakaichi en-aut-sei=Watanabe en-aut-mei=Takaichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=OnoTsutomu en-aut-sei=Ono en-aut-mei=Tsutomu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= affil-num=1 en-affil=Department of Applied Chemistry, Graduate School of Natural Science, Okayama University kn-affil= affil-num=2 en-affil=Department of Applied Chemistry, Graduate School of Natural Science, Okayama University kn-affil= affil-num=3 en-affil=Department of Applied Chemistry, Graduate School of Natural Science, Okayama University kn-affil= affil-num=4 en-affil=Department of Applied Chemistry, Graduate School of Natural Science, Okayama University kn-affil= END start-ver=1.4 cd-journal=joma no-vol=220 cd-vols= no-issue=9 article-no= start-page=1900021 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2019 dt-pub=20190403 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Rapid Synthesis of Poly(methyl methacrylate) Particles with High Molecular Weight by Soap‐Free Emulsion Polymerization Using Water‐in‐Oil Slug Flow en-subtitle= kn-subtitle= en-abstract= kn-abstract= flow process for the production of poly(methyl methacrylate) (PMMA) particles is proposed by soap‐free emulsion polymerization using a water‐in‐oil (W/O) slug flow in a microreactor. Thin oil films generated around the dispersed aqueous phase of the W/O slug prevent the prepared particles from adhesion to the microchannel wall, enabling the continuous production of PMMA particles without clogging. The effects of the linear flow rate of the slug flow and the addition of ethanol in the dispersed aqueous phase on the polymerization are evaluated. It is found that increasing the linear flow rate of the slug flow or the addition of ethanol in the dispersed aqueous phase results in PMMA particles with high molecular weight (≈1500 kg mol−1) in 20 min reaction time. It is believed that this process would be a promising way to prepare polymer particles with high molecular weight in a short reaction time. en-copyright= kn-copyright= en-aut-name=WatanabeTakaichi en-aut-sei=Watanabe en-aut-mei=Takaichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=KaritaKengo en-aut-sei=Karita en-aut-mei=Kengo kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=TawaraKoki en-aut-sei=Tawara en-aut-mei=Koki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=SogaTakuya en-aut-sei=Soga en-aut-mei=Takuya kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=OnoTsutomu en-aut-sei=Ono en-aut-mei=Tsutomu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= affil-num=1 en-affil=Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=2 en-affil=Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=3 en-affil=Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=4 en-affil=Department of Material and Energy Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=5 en-affil=Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University kn-affil= en-keyword=heterogeneous polymerization kn-keyword=heterogeneous polymerization en-keyword=internal circulation kn-keyword=internal circulation en-keyword=microreactors kn-keyword=microreactors en-keyword=microspheres kn-keyword=microspheres END start-ver=1.4 cd-journal=joma no-vol=520 cd-vols= no-issue= article-no= start-page=764 end-page=770 dt-received= dt-revised= dt-accepted= dt-pub-year=2017 dt-pub=20170220 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Indocyanine green-laden poly(ethylene glycol)-block-polylactide (PEG-b-PLA) nanocapsules incorporating reverse micelles: Effects of PEG-b-PLA composition on the nanocapsule diameter and encapsulation efficiency en-subtitle= kn-subtitle= en-abstract= kn-abstract=Reverse micelles are thermodynamically stable systems, with a capacity to encapsulate hydrophilic molecules in their nanosized core, which is smaller than the core generally obtained with water-in-oil-emulsion droplets. Herein, we present a simple technique for the preparation of poly(ethylene glycol)-block-polylactide (PEG-b-PLA) nanocapsules encapsulating a hydrophilic photosensitizer (indocyanine green, ICG), which exploits reverse micelle formation and subsequent emulsion-solvent diffusion. We establish the effect of the PEG-b-PLA composition and the co-surfactant volume on the diameter and water content of the reverse micelles. We demonstrate that the composition of PEG-b-PLA affects also the diameter and encapsulation efficiency of the resulting nanocapsules. We show that the ICG-laden nanocapsules fabricated under the most optimal conditions have a diameter of approximately 100 nm and an ICG encapsulation efficiency of 58%. We believe that the method proposed here is a promising step towards the preparation of hydrophilic drug-laden polymer nanocapsules with a small diameter and therefore suitable for use in drug delivery applications based on enhanced permeability and retention (EPR) effect-driven passive targeting. en-copyright= kn-copyright= en-aut-name=WatanabeTakaichi en-aut-sei=Watanabe en-aut-mei=Takaichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=SakamotoYui en-aut-sei=Sakamoto en-aut-mei=Yui kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=InookaTetsuya en-aut-sei=Inooka en-aut-mei=Tetsuya kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=KimuraYukitaka en-aut-sei=Kimura en-aut-mei=Yukitaka kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=OnoTsutomu en-aut-sei=Ono en-aut-mei=Tsutomu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= affil-num=1 en-affil=Department of Applied Chemistry and Biotechnology, Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=2 en-affil=Department of Applied Chemistry and Biotechnology, Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=3 en-affil=Division of Material and Energy Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=4 en-affil=Division of Material and Energy Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=5 en-affil=Department of Applied Chemistry and Biotechnology, Graduate School of Natural Science and Technology, Okayama University kn-affil= END start-ver=1.4 cd-journal=joma no-vol=4 cd-vols= no-issue=10 article-no= start-page=4872 end-page=4877 dt-received= dt-revised= dt-accepted= dt-pub-year=2013 dt-pub=20131210 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Monodisperse polylactide microcapsules with a single aqueous core prepared via spontaneous emulsification and solvent diffusion en-subtitle= kn-subtitle= en-abstract= kn-abstract=A simple approach to preparing monodisperse poly(D,L-lactide) (PDLLA) microcapsules with a single aqueous core is developed. The method is based on automatic water-in-oil-in-water double emulsion formation from oil-in-water single emulsion via spontaneous emulsification which voluntarily disperses part of continuous aqueous phase into the dispersed oil phase dissolving oil-soluble amphiphilic diblock copolymer, poly(D,L-lactide)-b-poly(2-dimethylaminoethyl methacylate)(PDLLA-b-PDMAEMA), followed by coalescence of tiny water droplets within the polymer droplets, coupled with quick precipitation of polymers by diluting the emulsion with water. In this study, we have investigated the effect of PDLLA to PDLLA-b-PDMAEMA ratios and flow rates of each solution during preparing the emulsion on the final morphology and the size of the microcapsules. It was found that the polymer blend ratio played a crucial role in determining internal structure of the microcapsules. The microcapsules size decreased with the increment of the flow rate ratios of the continuous phase to the dispersed phase and eventually reached 10 μm, while maintaining narrow size distribution. In addition, we have demonstrated that the microcapsules can encapsulate both hydrophilic and hydrophobic compounds during the formation. en-copyright= kn-copyright= en-aut-name=WatanabeTakaichi en-aut-sei=Watanabe en-aut-mei=Takaichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=KimuraYukitaka en-aut-sei=Kimura en-aut-mei=Yukitaka kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=OnoTsutomu en-aut-sei=Ono en-aut-mei=Tsutomu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= affil-num=1 en-affil=Department of Applied Chemistry and Biotechnology, Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=2 en-affil=Department of Material and Energy Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=3 en-affil=Department of Applied Chemistry and Biotechnology, Graduate School of Natural Science and Technology, Okayama University kn-affil= END start-ver=1.4 cd-journal=joma no-vol=35 cd-vols= no-issue=6 article-no= start-page=2358 end-page=2367 dt-received= dt-revised= dt-accepted= dt-pub-year=2019 dt-pub=20190110 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Microfluidic Formation of Hydrogel Microcapsules with a Single Aqueous Core by en-subtitle= kn-subtitle= en-abstract= kn-abstract=We report a simple process to fabricate monodisperse tetra-arm poly(ethylene glycol) (tetra-PEG) hydrogel microcapsules with an aqueous core and a semipermeable hydrogel shell through the formation of aqueous two-phase system (ATPS) droplets consisting of a dextran-rich core and a tetra-PEG macromonomer-rich shell, followed by a spontaneous cross-end coupling reaction of tetra-PEG macromonomers in the shell. Different from conventional techniques, this process enables for the continuous production of hydrogel microcapsules from water-in-oil emulsion droplets under mild conditions in the absence of radical initiators and external stimuli such as heating and ultraviolet light irradiation. We find that rapid cross-end coupling reaction of tetra-PEG macromonomers in ATPS droplets in the range of pH from 7.4 to 7.8 gives hydrogel microcapsules with a kinetically arrested core–shell structure. The diameter and core–shell ratio of the microcapsules can be easily controlled by adjusting flow rates and ATPS compositions. On the other hand, the slow cross-end coupling reaction of tetra-PEG macromonomers in ATPS droplets at pH 7.0 and lower induces structural change from core–shell to Janus during the reaction, which eventually forms hydrogel microparticles with a thermodynamically stable crescent structure. We believe that these hydrogel microparticles with controlled structures can be used in biomedical fields such as cell encapsulation, biosensors, and drug delivery carriers for sensitive biomolecules. en-copyright= kn-copyright= en-aut-name=WatanabeTakaichi en-aut-sei=Watanabe en-aut-mei=Takaichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=MotohiroIbuki en-aut-sei=Motohiro en-aut-mei=Ibuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=OnoTsutomu en-aut-sei=Ono en-aut-mei=Tsutomu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= affil-num=1 en-affil=Division of Applied Chemistry, Graduate School of Natural Science, Okayama University kn-affil= affil-num=2 en-affil=Division of Applied Chemistry, Graduate School of Natural Science, Okayama University kn-affil= affil-num=3 en-affil=Division of Applied Chemistry, Graduate School of Natural Science, Okayama University kn-affil= END start-ver=1.4 cd-journal=joma no-vol=30 cd-vols= no-issue=9 article-no= start-page=2470 end-page=2479 dt-received= dt-revised= dt-accepted= dt-pub-year=2014 dt-pub=2014029 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Microfluidic Approach to the Formation of Internally Porous Polymer Particles by Solvent Extraction en-subtitle= kn-subtitle= en-abstract= kn-abstract=We report the controlled formation of internally porous polyelectrolyte particles with diameters ranging from tens to hundreds of micrometers through selective solvent extraction using microfluidics. Solvent-resistant microdevices, fabricated by frontal photopolymerization, encapsulate binary polymer (P)/solvent (S1) mixtures by a carrier solvent phase (C) to form plugs with well-defined radii and low polydispersity; the suspension is then brought into contact with a selective extraction solvent (S2) that is miscible with C and S1 but not P, leading to the extraction of S1 from the droplets. The ensuing phase inversion yields polymer capsules with a smooth surface but highly porous internal structure. Depending on the liquid extraction time scale, this stage can be carried out in situ, within the chip, or ex situ, in an external S2 bath. Bimodal polymer plugs are achieved using asymmetrically inverted T junctions. For this demonstration, we form sodium poly(styrenesulfonate) (P) particles using water (S1), hexadecane (C), and methyl ethyl ketone (S2). We measure droplet extraction rates as a function of drop size and polymer concentration and propose a simple scaling model to guide particle formation. We find that the extraction time required to form particles from liquid droplets does not depend on the initial polymer concentration but is rather proportional to the initial droplet size. The resulting particle size follows a linear relationship with the initial droplet size for all polymer concentrations, allowing for the precise control of particle size. The internal particle porous structure exhibits a polymer density gradient ranging from a dense surface skin toward an essentially hollow core. Average particle porosities between 10 and 50% are achieved by varying the initial droplet compositions up to 15 wt % polymer. Such particles have potential applications in functional, optical, and coating materials. en-copyright= kn-copyright= en-aut-name=WatanabeTakaichi en-aut-sei=Watanabe en-aut-mei=Takaichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=LopezCarlos G. en-aut-sei=Lopez en-aut-mei=Carlos G. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=DouglasJack F. en-aut-sei=Douglas en-aut-mei=Jack F. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=OnoTsutomu en-aut-sei=Ono en-aut-mei=Tsutomu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=CabralJoão T. en-aut-sei=Cabral en-aut-mei=João T. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= affil-num=1 en-affil=Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=2 en-affil= Department of Chemical Engineering, Imperial College London kn-affil= affil-num=3 en-affil= Materials Science and Engineering Division, National Institute of Standards and Technology kn-affil= affil-num=4 en-affil=Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=5 en-affil=Department of Chemical Engineering, Imperial College London kn-affil= END start-ver=1.4 cd-journal=joma no-vol=29 cd-vols= no-issue=46 article-no= start-page=14082 end-page=14088 dt-received= dt-revised= dt-accepted= dt-pub-year=2013 dt-pub=20131029 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Microfluidic Fabrication of Monodisperse Polylactide Microcapsules with Tunable Structures through Rapid Precipitation en-subtitle= kn-subtitle= en-abstract= kn-abstract=We describe a versatile and facile route to the continuous production of monodisperse polylactide (PLA) microcapsules with controllable structures. With the combination of microfluidic emulsification, solvent diffusion, and internal phase separation, uniform PLA microcapsules with a perfluorooctyl bromide (PFOB) core were successfully obtained by simply diluting monodisperse ethyl acetate (EA)-in-water emulsion with pure water. Rapid extraction of EA from the droplets into the aqueous phase enabled the solidification of the polymer droplets in a nonequilibrium state during internal phase separation between a concentrated PLA/EA phase and a PFOB phase. Higher-molecular-weight PLA generated structural complexity of the microcapsules, yielding core–shell microcapsules with covered with small PFOB droplets. Removal of the PFOB via freeze drying gave hollow microcapsules with dimpled surfaces. The core–shell ratios and the diameter of these microcapsules could be finely tuned by just adjusting the concentration of PFOB and flow rates on emulsification, respectively. These biocompatible microcapsules with controllable size and structures are potentially applicable in biomedical fields such as drug delivery carriers of many functional molecules. en-copyright= kn-copyright= en-aut-name=WatanabeTakaichi en-aut-sei=Watanabe en-aut-mei=Takaichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=KimuraYukitaka en-aut-sei=Kimura en-aut-mei=Yukitaka kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=OnoTsutomu en-aut-sei=Ono en-aut-mei=Tsutomu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= affil-num=1 en-affil=Department of Chemistry and Biotechnology, Graduate School of Natural Science and Technolog kn-affil= affil-num=2 en-affil=Department of Material and Energy Science, Graduate School of Environmental and Life Science, Okayama University kn-affil= affil-num=3 en-affil=Department of Chemistry and Biotechnology, Graduate School of Natural Science and Technology kn-affil= END start-ver=1.4 cd-journal=joma no-vol=16 cd-vols= no-issue=6 article-no= start-page=1572 end-page=1581 dt-received= dt-revised= dt-accepted= dt-pub-year=2019 dt-pub=20191223 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Preparation of tough, thermally stable, and water-resistant double-network ion gels consisting of silica nanoparticles/poly(ionic liquid)s through photopolymerisation of an ionic monomer and subsequent solvent removal en-subtitle= kn-subtitle= en-abstract= kn-abstract=We report the preparation of tough, thermally stable, and water-resistant double-network (DN) ion gels, which consist of a partially-clustered silica nanoparticle network and poly(ionic liquid) (PIL) network holding an ionic liquid. Silica nanoparticles/poly([Evim][Tf2N]) DN ion gels are prepared by photo-induced radical polymerisation of [Evim][Tf2N] in a mixture containing silica nanoparticles, [Bmim][Tf2N], ionic liquid based cross-linker [(VIM)2C4][Tf2N]2, and ethyl acetate, followed by subsequent solvent evaporation. Tensile strength measurements show that the mechanical properties of the PIL DN ion gels were higher than those of the PIL single-network (SN) ion gel. A rheological study indicates that an enhancement in mechanical strength of the PIL DN ion gels can be achieved when silica nanoparticles form partial clusters in [Bmim][Tf2N]. The cyclic stress–strain measurement of the PIL DN ion gels shows hysteresis loops, suggesting that the silica nanoparticle clusters rupture and dissipate the loading energy when the PIL DN ion gels undergo a large deformation. The fracture strength and Young's modulus of the PIL DN ion gels increase as the diameter of the silica nanoparticles is decreased. Thermogravimetric analysis measurement shows that the PIL DN ion gel has a high decomposition temperature of approximately 400 °C. Moreover, the swelling test shows that the PIL DN ion gel possesses an excellent water-resistant property because of the hydrophobic nature of the PIL backbone. We believe that such tough, thermally stable, and water-resistant PIL DN ion gels can be used as carbon dioxide separation membranes, sensors, and actuators for soft robotics. en-copyright= kn-copyright= en-aut-name=WatanabeTakaichi en-aut-sei=Watanabe en-aut-mei=Takaichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=TakahashiRuri en-aut-sei=Takahashi en-aut-mei=Ruri kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=OnoTsutomu en-aut-sei=Ono en-aut-mei=Tsutomu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= affil-num=1 en-affil=Department of Applied Chemistry, Graduate School of Natural Science, Okayama University kn-affil= affil-num=2 en-affil=Department of Applied Chemistry, Graduate School of Natural Science, Okayama University kn-affil= affil-num=3 en-affil=Department of Applied Chemistry, Graduate School of Natural Science, Okayama University kn-affil= END start-ver=1.4 cd-journal=joma no-vol=7 cd-vols= no-issue=21 article-no= start-page=9894 end-page=9897 dt-received= dt-revised= dt-accepted= dt-pub-year=2011 dt-pub=20110913 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Continuous fabrication of monodisperse polylactide microspheres by droplet-to-particle technology using microfluidic emulsification and emulsion–solvent diffusion en-subtitle= kn-subtitle= en-abstract= kn-abstract=Monodisperse polylactide (PLA) microspheres were continuously fabricated by microfluidic emulsification and subsequent dilution in water. The diameter was precisely tuned from 6 to 50 μm by changing the flow rate of the fluids in microfluidics or the PLA concentration in the dispersed phase. The use of amphiphilic oil-soluble poly(ethylene glycol)-b-polylactide (o-PEG–PLA) as a matrix resulted in a highly porous microsphere morphology, and the porosity was controlled by blending PLA. Therefore, monodisperse PLA microspheres with the predetermined surface porosity were continuously produced by just enough reagents and energy. en-copyright= kn-copyright= en-aut-name=WatanabeTakaichi en-aut-sei=Watanabe en-aut-mei=Takaichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=OnoTsutomu en-aut-sei=Ono en-aut-mei=Tsutomu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=KimuraYukitaka en-aut-sei=Kimura en-aut-mei=Yukitaka kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= affil-num=1 en-affil=Department of Material and Energy Science, Graduate School of Environmental Science, Okayama University kn-affil= affil-num=2 en-affil=Department of Material and Energy Science, Graduate School of Environmental Science, Okayama University kn-affil= affil-num=3 en-affil=Department of Material and Energy Science, Graduate School of Environmental Science, Okayama University kn-affil= END start-ver=1.4 cd-journal=joma no-vol=298 cd-vols= no-issue= article-no= start-page=1273 end-page=1281 dt-received= dt-revised= dt-accepted= dt-pub-year=2020 dt-pub=20200717 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Flow synthesis of monodisperse micron-sized polymer particles by heterogeneous polymerization using a water-in-oil slug flow with a non-ionic surfactant en-subtitle= kn-subtitle= en-abstract= kn-abstract=Flow synthesis of poly(methyl methacrylate) particles was performed by heterogeneous polymerization of methyl methacrylate using a water-in-oil (W/O) slug flow with or without a non-ionic surfactant in the continuous organic phase. It was found that undesired phenomena in this polymerization system, clogging of the channel and broadening particle size distribution, can occur when growing polymer particles adsorb to the W/O interface during polymerization, and that the addition of non-ionic surfactant to the continuous organic phase prevents the particles from adsorption to the W/O interface and gives monodisperse polymer particles. In addition, it was shown that as the initiator concentration increases, the particle diameter becomes larger, resulting in monodisperse micron-sized polymer particles with 100% monomer conversion at a 120-min reaction time. These results indicated that the heterogeneous polymerization process using a W/O slug flow can be a promising way to continuously prepare monodisperse polymer particles with micron sizes in a short reaction time. en-copyright= kn-copyright= en-aut-name=WatanabeTakaichi en-aut-sei=Watanabe en-aut-mei=Takaichi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=KaritaKengo en-aut-sei=Karita en-aut-mei=Kengo kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=OnoTsutomu en-aut-sei=Ono en-aut-mei=Tsutomu kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= affil-num=1 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=2 en-affil=Department of Applied Chemistry, Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=3 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= en-keyword=Microreactor kn-keyword=Microreactor en-keyword=Heterogeneous polymerization kn-keyword=Heterogeneous polymerization en-keyword=Slug flow kn-keyword=Slug flow en-keyword=Monodisperse kn-keyword=Monodisperse en-keyword=Micron-sized particle kn-keyword=Micron-sized particle END