Preparation of polymeric Janus microparticles with hierarchically porous structure and enhanced anisotropy

Qiaohong Peng; Hailin Cong; Bing Yu; Li Wei; Khalid Mahmood; Hua Yuan; Ruixia Yang; Xiaoyan Zhang; Yue Wu

doi:10.1016/j.jcis.2018.03.066

Preparation of polymeric Janus microparticles with hierarchically porous structure and enhanced anisotropy

J Colloid Interface Sci. 2018 Jul 15:522:144-150. doi: 10.1016/j.jcis.2018.03.066. Epub 2018 Mar 21.

Authors

Qiaohong Peng¹, Hailin Cong², Bing Yu³, Li Wei¹, Khalid Mahmood⁴, Hua Yuan¹, Ruixia Yang¹, Xiaoyan Zhang¹, Yue Wu¹

Affiliations

¹ Institute of Biomedical Materials and Engineering, College of Materials Science and Engineering, Qingdao University, 308 Ningxia Road, Qingdao, Shangdong 266071, China.
² Institute of Biomedical Materials and Engineering, College of Materials Science and Engineering, Qingdao University, 308 Ningxia Road, Qingdao, Shangdong 266071, China; Laboratory for New Fiber Materials and Modern Textile, Growing Base for State Key Laboratory, College of Chemical Engineering, Qingdao University, China. Electronic address: conghailin@qdu.edu.cn.
³ Institute of Biomedical Materials and Engineering, College of Materials Science and Engineering, Qingdao University, 308 Ningxia Road, Qingdao, Shangdong 266071, China; Laboratory for New Fiber Materials and Modern Textile, Growing Base for State Key Laboratory, College of Chemical Engineering, Qingdao University, China.
⁴ Institute of Chemical Sciences, Bahauddin Zakariya University, Multan, Pakistan.

PMID: 29597126
DOI: 10.1016/j.jcis.2018.03.066

Abstract

Anisotropic Janus particles are of great interest for many applications. It is well known that behavior and utility of Janus particles are highly dependent on their chemistry and geometry. Herein, we report the synthesis of monodisperse polymeric Janus microparticles that were anisotropic not only in chemistry and shape but also in surface morphology and porosity, via a modified seeded polymerization technique. Chemical composition, shape, morphology and porosity of the polymeric Janus microparticles were flexibly controlled by utilizing different quantities and species of monomer and porogen. The polymeric Janus microparticles exhibited hierarchically porous structure, including micro- and meso-pores as evidenced by isothermal nitrogen adsorption and desorption. Due to the high specific surface area, anisotropy of the polymeric Janus microparticles was enhanced according to the greater fluorescence contrast on distinct sides of the polymeric Janus microparticles. Moreover, swelling and phase-separation processes of cross-linked seeds were in situ observed on an optical microscope to demonstrate the formation mechanism of the polymeric Janus microparticles.

Keywords: Anisotropy; Polymeric Janus particles; Porosity; Swelling kinetics.