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A series of poly(dodecafluoroheptyl methacrylate)-b-poly(methyl methacrylate) (PDFMA-b-PMMA) diblock copolymer nanoparticles were prepared by reversible addition-fragmentation chain transfer (RAFT) dispersion polymerization of methyl methacrylate (MMA) in supercritical carbon dioxide. Nuclear Magnetic Resonance (NMR) and gel permeation chromatography (GPC) analysis confirmed an efficient and wellcontrolled block copolymerization. As the length of the PMMA block grows from the soluble PDFMA block it eventually becomes insoluble, which drives in situ polymerization-induced self-assembly (PISA). The influences of the length of CO 2 -philic PDFMA block, CO 2 -phobic PMMA block and polymerization pressure were investigated in this PISA process. Also spherical nano-objects were formed upon the synthesis of amphiphilic diblock copolymers in situ. It appeared that, as the length of CO 2 -philic block PDFMA was increased, there was a corresponding decrease in particle size and particle size polydispersity. Scanning electron microscope (SEM) images revealed that, during the microspheres formation, the greater degree of polymerization (DP) of MMA favoured well-controlled monodisperse microspheres. a Reactions performed with [MMA] ¼ 0.8 M, [PDFMA-CDB] : [AIBN] ¼ 2 : 1, in 50 ml high-pressure autoclave at 70 C and 30 MPa for 24 h. b M n,th ¼ (([MMA] 0 )/[PDFMA-CDB] 0 ) Â M MMA + M PDFMA-CDB . c Gel permeation chromatography (GPC) in tetrahydrofuran with PS standards. dThe degree of polymerization (DP) for each polymer was calculated by the GPC. The degree of polymerization of the second block PMMA, DP nPMMA were determined by using the following formula: DP n ¼ [(M n of diblock copolymer PDFMA-b-PMMA À M n,NMR of PDFMA-CDB)/molecular weight of MMA monomer]. e Based on the visual observations made immediately aer the recovery of the polymers from the reactor, SB ¼ solid block, WP ¼ white powder. f D n ¼ particle size. g D w /D n ¼ size distribution. n.a.: not applicable. This journal is

A facile preparation for a series of porous poly(2,2,2-trifluoroethylmethacrylate–divinylbenzene) P(TFEMA–DVB) foams is discussed in this paper.

High internal phase emulsion (HIPE) technique has been of great interest for fabrication of polymer foams with controlled porous structures. However, for fluoropolymers, it has been a challenge to fabricate high-performance foams with controllable porous structures by HIPE due to the lack of suitable surfactant. Here, for the first time, a new type of cationic fluorosurfactant (CFS) is proposed to address this issue. The cationic fluorosurfactant is a diblock copolymer, Poly(2-dimethylamino)ethyl methacrylate-b-Poly(hexafluorobutyl acrylate) (PDMAEMA-b-PHFBA) synthesized by reversible addition−fragmentation chain transfer (RAFT) polymerization. For the prepared fluoro-diblock copolymer having similar fluorosegments to fluoro-monomer, this cationic fluorosurfactant can effectively stabilize high internal phase