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Cadmium sulfide (CdS) nanodots in polymeric colloidal reactors were prepared by seeded inverse emulsion polymerization and then crystallized solvothermally. The cadmium sulfate (CdSO 4 )-polyacrylamide (PAM) seeds were synthesized by inverse miniemulsion polymerization with CdSO 4 solution as a co-stabilizer. The prepared CdSO 4 -PAM particles were used as polymeric colloidal reactors for the formation of CdS-PAM by feeding the mixed solution of sodium sulfide (Na 2 S) and acrylamide. The effects of the feeding rate on the size, distribution and morphologies of particles were investigated. The influences of the solvothermal treating temperature and time on the crystallite size were characterized. The CdS was well formed and then crystallized in the PAM colloidal reactors. The crystals growth mechanism was taken under consideration. The crystallite size was calculated by the X-ray diffraction (XRD) data, and their morphologies were observed by transmission electron microscopy (TEM). The small CdS crystals showed a blue-shift on the spectra of ultraviolet visible absorption and fluorescence emission. The small CdS crystals displayed the desired property of photocatalytic degradation. [ABSTRACT FROM AUTHOR]

Highlights: [•] The fluorinated block copolymer is prepared by ATRP. [•] The copolymers are used as sole co-stabilizer in the miniemulsion polymerization. [•] The fluorine content in copolymer has effect on the process of miniemulsion. [•] The final latex films show the better surface hydrophobicity. [•] The nucleation mechanism of miniemulsion polymerization is proposed. [ABSTRACT FROM AUTHOR]

The poly sodium polyacrylate (PAANa) latex particles containing hybrid nanocrystals of bismuth tungstate-cadmium sulfide (Bi 2 WO 6 -CdS) were prepared by the combination process of inverse miniemulsion, absorption, and solvothermal treatment. The Bi 2 WO 6 -PAANa latex particles and CdS-PAANa latex particles were prepared by inverse miniemulsion polymerization for formation of CdS based on Bi 2 WO 6 (Bi 2 WO 6 /CdS) and Bi 2 WO 6 based on CdS (CdS/Bi 2 WO 6) hybrid nanocrystals, respectively. The effects of dropping strategies in absorption and solvothermal treatment condition on the size, their distribution and the morphologies of Bi 2 WO 6 /CdS-PAANa and CdS/Bi 2 WO 6 -PAANa latex particles were investigated. The dropping in order was better than simultaneous dropping in absorption process. The clustered Bi 2 WO 6 /rod-like CdS and the punctate CdS/punctate Bi 2 WO 6 hybrid nanocrystals could be grown under the same solvothermal conditions. The influences of cadmium sulfate/sodium sulfide (CdSO 4 /NaS) millimolar number on the grain size and the morphologies of Bi 2 WO 6 /CdS hybrid nanocrystals were investigated. With the CdSO 4 /NaS millimolar number increase, the grain size of CdS rod-like and Bi 2 WO 6 cluster gradually increased due to oriented attachment and Ostwald ripening, respectively. The Bi 2 WO 6 -CdS hybrid nanocrystals will perform the excellent photoelectric properties. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO) @ poly (N -isopropyl acrylamide (NIPAM)) (PNIPAM) nanospheres, which the modified ZnO nanoparticles had attached on the interface-layer of PNIPAM, were a special structure material prepared by inverse Pickering miniemulsion polymerization. The original ZnO nanoparticles were synthesized by the sol-gel method and then their surfaces were modified to be partly hydrophobic. The NIPAM inverse Pickering miniemulsion was polymerized to form ZnO@PNIPAM nanospheres, using the modified ZnO nanoparticles as a solid surfactant. The influences of the dosage ratios of modifier to original ZnO nanoparticles on size, distribution and surface hydrophobicity of the modified ZnO nanoparticles were discussed. The self-assembly mechanism of the modified ZnO nanoparticles on the oil/water interface was suggested. The effect of dosage and size of the modified ZnO nanoparticles on miniemulsion stability and polymerization was researched. The nanospheres with the specific ZnO@PNIPAM structure and good dispersibility could be successfully prepared by the inverse Pickering miniemulsion method. The extracted ZnO@PNIPAM nanospheres simultaneously exhibited strong ultraviolet-visible absorption characteristics and luminescence intensity. [ABSTRACT FROM AUTHOR]

Bismuth tungstate (Bi 2 WO 6)-sodium polyacrylate (PAANa) latex particles were prepared by inverse miniemulsion and hydrothermal treatment. The effects of Bi(NO 3) 3 /Na 2 WO 4 dosage ratio and different hydrothermal treatment conditions on the particle size and morphology of Bi 2 WO 6 -PAANa latex particles were studied. The results show that the stability of the inverse microemulsion droplets was effectively improved with the increase of the soluble salt in the inverse microemulsion system, and the effect of different hydrothermal treatment on the particle size of the colloidal particles was not significant. During the formation of Bi 2 WO 6 nanoparticles, PAANa latex particles could become a reaction site for forming Bi 2 WO 6 nanoparticles, and Bi 2 WO 6 nanoparticles were dispersed in the polymer. The effects of different hydrothermal treatment conditions on the size, crystal form and light absorption properties of Bi 2 WO 6 nanocrystals were studied. The results show that Bi 2 WO 6 nanoparticles with orthorhombic tungsten-rhenium ore structure could be prepared under different hydrothermal treatment conditions; moreover, the temperature at which the hydrothermal treatment forms the lowest Bi 2 WO 6 nanocrystals was 130 °C. But at pH 9, the product was no longer pure phase. The prepared nanocrystals simultaneously exhibited strong ultraviolet-visible absorption characteristics and luminescence intensity. Finally, the Bi 2 WO 6 nanoparticles with photoluminescence properties could be successfully prepared by the inverse miniemulsion method. [ABSTRACT FROM AUTHOR]