Coreshell polymers: a review,RSC Adv. , 2013, 3, 15543-15565,Reporter:Rui NiuJianwu GuoXiaobo Teng2013.11.20,Content,1.Introduction 2.Classifications 3.Preparation of core-shell 4.Development of latex particle morphology of CPS 5.Characterizations 6.Recent study on core-shell polymers 7.Applications 8.conclusion,1.Introduction,In1961,Hughes and Brown investigated the physical properties of coreshell polymer (CSP) and their interesting morphology. This class of material has attracted much attention because of the combination of superior properties not possessed by the individual components. The systems might combine the characteristics and properties of both shell and core where the surface properties of the shell are translated to the core,imparting new functionality to the CSP. Macromolecules, 2003, 36 (6), 19881993.,CSPs are structured composite particles consisting of at least two different components, one in principle forms the core and another forms the shell of the particles.,2. Classification,Core shell polymers (CSPs),State,Hydrogels,NIPAM,Non-NIPAM,Conventionalmonomer,Acrylamide derivatives,Size,Nano,Micro,Non-Hydrogels,Non-aqueous,Organic-inorganic,Single,2.1 Coreshell polymer hydrogels,Property: CSP hydrogels have been produced either to modify the stability and physical properties of the polymers or to impart stimuli-responsive properties to responsive particles.,Application: CSP hydrogels made of smart materials have widespread applications, especially in biomedical areas, as their response to surrounding environmental changes such as temperature and pH,etc.,Adv. Drug Delivery Rev. , 1996 ,18 (2), 219267. Macromolecules, 1998 ,31 (25), 89128917.,2.1.1 NIPAM based CSP hydrogels,32,switchable or smart materials, poly (N -isopropylacrylamide PNIPAM) has been extensively used as a main component in CSP hydrogels due to its thermoresponsive properties.,Macromolecules, 1998 , 31 (25), 89128917,Langmuir, 2004 ,20 (11), 43304335,J. Colloid Interface Sci. , 2012, 376 (1), 97106.,2.1.2 Non-NIPAM CSP hydrogel,non-NIPAM CSPs (conventional monomer ),hydrophilic AAm,hydrophilic AAc,hydrophobic MMA,hydrophobic St.,produce responsive CSPs,non-NIPAM CSPs (acrylamide derivatives),NIPMAM,NNPAM,N-ethylacrylamide,N-vinylisobutylacrylamide,used to polymerize temperature-sensitive microgels,2.2 Non-hydrogel coreshell polymer,Non Hydrogels,Non-aqueous,Organic-inorganic,Single,Core: solid polymer particle or rubber Shell: hard polymer Used: paints, coating applications, pigments, binder,Used：nanotechnology and biomedical applications, such as a signal-molecular template , live-cell imaging, drug carrier and drug release.,Def: non-cross linked CSPs consisting of amphiphilic block or graft polymers in which hydrophobic and hydrophilic segments are covalently connected with the dendritic or hyperbranched core-shell.,在下面介绍,J. Am. Chem. Soc. , 2010 , 132(35), 1221812221,synthesis of new functional materials for light-emitting devices, solar cells, photodetectors , biomedical and sensor applications.,Core,surfactant,poly (ethylene oxide),poly (vinyl benzyl chloride),poly (vinyl pyrrolidone ),polymer,different copolymers,poly ( styrene acrylic acid),Shell,metals,metal oxides,metal chalcogenides,silica,Adv. Mater. , 2009 ,21 (5), 509534.,J. Mater. Chem. , 2012 ,22 (22), 1137011378.,Used,Inorganicorganic CSPs,butadiene,styrene,3. Preparation of coreshell polymers,CSPs are typically prepared by a series of consecutive, emulsion, dispersion or precipitation polymerization sequences with different monomer type.,CSP particles,multi-step,One-stage reaction: a facile method to prepare polymer particles with coreshell morphology.,seed particles as a core material,second or third stage monomer is polymerized in the seed latex particles,Disadvantage: expensive , timeconsuming,Chim. Acta, 2003 , 496(12), 5363.,Macromolecules, 2009 ,42 (13), 45114519., consecutive emulsion,Dispersion polymerization： a class of larger particles and irregular shape of polymer particles were produced in precipitation polymerization. polymer particles in the range of 115 m. The formed polymers are insoluble in continuous phase .,Based on ploymerization classes,emulsion polymerization : the main process for the preparation of commercial emulsion, which involves a monomer that has limited solubility in water. particle diameter is typically within the range of 110 m.,Macromolecules, 2009 ,42 (13), 45114519,Part A: Polym. Chem. , 2001 ,39 (19), 34343442,Example Fig. 3 illustrates common methods to prepare CSPs described by Li and Stover.,emulsion polymerization using reactive surfactants,Two-stage emulsion polymerization was the first general method,step-wise heterocoagulation of smaller cationic polymer particles onto larger anionic, heat treatment .,block copolymers can be used to produce coreshell type polymer nanospheres via block copolymerization .,3.1 Emulsion polymerization,Emulsion polymerization synthesized process is commonly used to produce water based resins with a variety of physicochemical and colloidal properties.,