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Cadmium sulfide/zinc sulfide (CdS/ZnS) core-shell nanoparticles in polyacrylamide (PAM) colloid particle were prepared by the succession of inverse miniemulsion polymerization and absorption. The cadmium sulfate (CdSO4)-PAM colloid was firstly prepared by inverse miniemulsion polymerization, the CdS nanoparticles were formed by reaction between CdSO4 in PAM particles and excessive sodium sulfide in being-absorbed miniemulsion droplets; and then the ZnS nanoparticles were orientated-grew onto CdS nanoparticles by slowly absorbing zinc acetate in miniemulsion droplets. The effects of the Cd2+/Zn2+ molar ratios on CdS/ZnS-PAM particles preparation were investigated. When the Cd2+/Zn2+molar ratio was 1:1, the Z average diameter of the CdS/ZnS-PAM particles was 178 nm. The CdS/ZnS crystals showed a greater size with Zn2+ mole fraction increase. The core-shell structure of CdS/ZnS nanoparticles was confirmed successfully by transmission electron microscopy observation, X-ray diffraction analysis and so on. The ZnS shell layer played an important role in modification and reduced the surface defects of nanocrystals effectively. The succession method will provide a great advantage in core-shell structure CdS/ZnS preparation. [ABSTRACT FROM AUTHOR]

Hexafluorobutyl methacrylate (HFMA) was predissolved as sole co-stabilizers in miniemulsions in order to improve the surface properties of films prepared by final latex, and a semibatch polymerization was used for enhancing the HFMA usage efficiency. In miniemulsion polymerization, the effects of the HFMA on the stability of monomer droplet were investigated. The ratio of the final latex particles number to the initial monomer droplets number was used to discuss the nucleation formation process. In a semibatch minimeulsion reaction, the effect of HFMA dropping policy on the size of final latex particles was discussed and morphology of the latex particles observed. Although the HFMA consumption was equal in all semibatch experiments, the surface properties of film prepared by final latex demonstrated a strong difference. [ABSTRACT FROM AUTHOR]