{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T20:15:18Z","timestamp":1792008918795,"version":"4.4.0"},"reference-count":26,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2018,1,12]],"date-time":"2018-01-12T00:00:00Z","timestamp":1515715200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Micromachines"],"abstract":"<jats:p>Monodisperse resorcinol formaldehyde resin (RF) microspheres are an important polymeric material because of their rich surface functional group and uniform structural characteristics and have been increasingly applied as an electrode material, catalyst support, absorbent, and carbon microsphere precursor. The polymerization conditions, such as the gelation\/solidification temperature and the residence time, can largely influence the physical properties and the formation of the 3D polymeric network of the RF microspheres as well as the carbon microspheres. However, few studies have reported on the complexity of the gelation and solidification processes of resol. In this work, we developed a new RF microsphere preparation device that contains three units: a droplet generation unit, a curing unit, and a collection unit. In this system, we controlled the gelation and solidification processes of the resol and observed its curing behavior, which helped us to uncover the curing mechanism of resol. Finally, we obtained the optimized polymerization parameters, obtaining uniform RF microspheres with a variation coefficient of 4.94%. The prepared porous RF microspheres presented a high absorption ability, reaching ~90% at 10 min. Thus, our method demonstrated the practicality of on-chip monodisperse microspheres synthesis. The product was useful in drug delivery and adsorbing large poisonous molecules.<\/jats:p>","DOI":"10.3390\/mi9010024","type":"journal-article","created":{"date-parts":[[2018,1,15]],"date-time":"2018-01-15T04:01:55Z","timestamp":1515988915000},"page":"24","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["On-Chip Facile Preparation of Monodisperse Resorcinol Formaldehyde (RF) Resin Microspheres"],"prefix":"10.3390","volume":"9","author":[{"given":"Jianmei","family":"Wang","sequence":"first","affiliation":[{"name":"School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China"},{"name":"Energy Research Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250014, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaowen","family":"Huang","sequence":"additional","affiliation":[{"name":"Energy Research Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250014, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pei","family":"Zhao","sequence":"additional","affiliation":[{"name":"Energy Research Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250014, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xueying","family":"Wang","sequence":"additional","affiliation":[{"name":"Energy Research Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250014, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ye","family":"Tian","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chengmin","family":"Chen","sequence":"additional","affiliation":[{"name":"Energy Research Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250014, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jianchun","family":"Wang","sequence":"additional","affiliation":[{"name":"Energy Research Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250014, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yan","family":"Li","sequence":"additional","affiliation":[{"name":"Energy Research Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250014, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wei","family":"Wan","sequence":"additional","affiliation":[{"name":"Energy Research Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250014, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hanmei","family":"Tian","sequence":"additional","affiliation":[{"name":"Energy Research Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250014, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Min","family":"Xu","sequence":"additional","affiliation":[{"name":"Energy Research Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250014, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chengyang","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Liqiu","family":"Wang","sequence":"additional","affiliation":[{"name":"Energy Research Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250014, China"},{"name":"Department of Mechanical Engineering, The University of Hong Kong, Hong Kong, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,1,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"96","DOI":"10.1016\/j.jhazmat.2015.11.022","article-title":"Moisture insensitive adsorption of ammonia on resorcinol-formaldehyde resins","volume":"305","author":"Seredych","year":"2016","journal-title":"J. Hazard. Mater."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"169","DOI":"10.1016\/j.jelechem.2016.03.011","article-title":"Morphology-tuned preparation of nanostructured resorcinol-formaldehyde carbonized polymers as highly sensitive electrochemical sensor for amaranth","volume":"779","author":"Ji","year":"2016","journal-title":"J. Electroanal. Chem."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"15831","DOI":"10.1039\/C5RA27605E","article-title":"Chain-like Fe3O4@resorcinol-formaldehyde resins\u2013ag composite microstructures: Facile construction and applications in antibacterial and catalytic fields","volume":"6","author":"Zhong","year":"2016","journal-title":"RSC Adv."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"31677","DOI":"10.1039\/C5RA01506E","article-title":"Preparation of biocompatible and antibacterial carbon quantum dots derived from resorcinol and formaldehyde spheres","volume":"5","author":"Roy","year":"2015","journal-title":"RSC Adv."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"833","DOI":"10.1002\/adma.200902550","article-title":"An aqueous emulsion route to synthesize mesoporous carbon vesicles and their nanocomposites","volume":"22","author":"Gu","year":"2010","journal-title":"Adv. Mater."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"3084","DOI":"10.1021\/ie4029939","article-title":"Preparationof ultrafine carbon spheres bycontrolledpolymerization of furfuryl alcohol in microdroplets","volume":"53","author":"Ju","year":"2014","journal-title":"Ind. Eng. Chem. Res."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"85","DOI":"10.1016\/j.carbon.2012.08.015","article-title":"On the effects of emulsion polymerization of furfuryl alcohol on the formation of carbon spheres and other structures derived by pyrolysis of polyfurfuryl alcohol","volume":"51","author":"Peer","year":"2013","journal-title":"Carbon"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1851","DOI":"10.1002\/ange.200604206","article-title":"Fabrication of monodisperse gel shells and functional microgels in microfluidic devices","volume":"119","author":"Kim","year":"2015","journal-title":"Angew. Chem."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1063\/1.4816714","article-title":"Poly(vinyl alcohol)-heparin biosynthetic microspheres produced by microfluidics and ultraviolet photopolymerisation","volume":"7","author":"Young","year":"2013","journal-title":"Biomicrofluidics"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"905","DOI":"10.1038\/nchem.1753","article-title":"The past, present and potential for microfluidic reactor technology in chemical synthesis","volume":"5","author":"Elvira","year":"2013","journal-title":"Nat. Chem."},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Wang, J., Li, Y., Wang, X., Wang, J., Tian, H., Zhao, P., Tian, Y., Gu, Y., Wang, L., and Wang, C. (2017). Droplet microfluidics for the production of microparticles and nanoparticles. Micromachine, 8.","DOI":"10.3390\/mi8010022"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"11701","DOI":"10.1021\/acs.langmuir.5b03192","article-title":"One-pot synthesis of monodisperse noble metal @ resorcinol-formaldehyde (M@RF) and M@Carbon core\u2013shell nanostructure and their catalytic applications","volume":"31","author":"Yang","year":"2015","journal-title":"Langmuir"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"180","DOI":"10.1016\/j.colsurfa.2016.01.009","article-title":"Porous structure and pore size control of mesoporous carbons using a combination of a soft-templating method and a solvent evaporation technique","volume":"494","author":"Mitome","year":"2016","journal-title":"Colloids Surf. A Physicochem. Eng. Asp."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"150","DOI":"10.1016\/j.matchemphys.2016.06.044","article-title":"Scalable preparation of hollow polymer and carbon microspheres by spray drying and their application in low-density syntactic foam","volume":"181","author":"Zhou","year":"2016","journal-title":"Mater. Chem. Phys."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"527","DOI":"10.1002\/marc.200600776","article-title":"Exploring microfluidic routes to microgels of biological polymers","volume":"28","author":"Zhang","year":"2007","journal-title":"Macromol. Rapid Commun."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"179","DOI":"10.1063\/1.4738586","article-title":"Droplet based microfluidic fabrication of designer microparticles for encapsulation applications","volume":"6","author":"Kong","year":"2012","journal-title":"Biomicrofluidics"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"370","DOI":"10.1016\/j.fuel.2016.08.014","article-title":"Aerodynamic breakup of an n -decane droplet in a high temperature gas environment","volume":"185","author":"Strotos","year":"2016","journal-title":"Fuel"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"45","DOI":"10.1016\/j.polymer.2015.05.016","article-title":"On the synthesis and structure of resorcinol-formaldehyde polymeric networks\u2014Precursors to 3D-carbon macroassemblies","volume":"69","author":"Lewicki","year":"2015","journal-title":"Polymer"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"2887","DOI":"10.1002\/adma.201100283","article-title":"Advances in tailoring resorcinol-formaldehyde organic and carbon gels","volume":"23","author":"Elkhatat","year":"2011","journal-title":"Adv. Mater."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"6166","DOI":"10.1021\/la4007422","article-title":"Carbon xerogel microspheres and monoliths from resorcinol-formaldehyde mixtures with varying dilution ratios: Preparation, surface characteristics, and electrochemical double-layer capacitances","volume":"29","year":"2013","journal-title":"Langmuir"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"62","DOI":"10.1016\/j.polymer.2016.12.069","article-title":"Kinetics of early stages of resorcinol-formaldehyde polymerization investigated by solution-phase nuclear magnetic resonance spectroscopy","volume":"110","author":"Gaca","year":"2017","journal-title":"Polymer"},{"key":"ref_22","first-page":"58","article-title":"The electrochemical performance of phenolic resin based activated carbon microbeads\u2014I. an investigation on the preparation of the microbeads","volume":"20","author":"Wang","year":"2005","journal-title":"New Carbon Mater."},{"key":"ref_23","unstructured":"Huang, F.R., and Wan, L.Q. (2011). Phenol Formaldehyde Resin and Its Application, Chemical Industry Press."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"18","DOI":"10.1016\/S1369-7021(08)70053-1","article-title":"Designer emulsions using microfluidics","volume":"11","author":"Shah","year":"2008","journal-title":"Mater. Today"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"2952","DOI":"10.1039\/C7TB00101K","article-title":"Construction of blood compatible lysine-immobilized chitin\/carbon nanotubes microspheres and potential applications for blood purified therapy","volume":"5","author":"Wu","year":"2017","journal-title":"J. Mater. Chem. B"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"720","DOI":"10.1631\/jzus.B1500101","article-title":"Evaluation of efficacy of resin hemoperfusion in patients with acute 2,4-dinitrophenol poisoning by dynamic monitoring of plasma toxin concentration","volume":"16","author":"Zhao","year":"2015","journal-title":"J. Zhejiang Univ. Sci. B"}],"container-title":["Micromachines"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-666X\/9\/1\/24\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T14:51:00Z","timestamp":1760194260000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-666X\/9\/1\/24"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,1,12]]},"references-count":26,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2018,1]]}},"alternative-id":["mi9010024"],"URL":"https:\/\/doi.org\/10.3390\/mi9010024","relation":{},"ISSN":["2072-666X"],"issn-type":[{"value":"2072-666X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2018,1,12]]}}}