研究生文献汇报课件.ppt

3.2 Dispersion polymerization This technique allows synthesis of micro particles in the range of 1–15microns. Most of the ingredients in this process, including surfactant, initiators and monomers, are soluble in continuous organic phase and which form polymers that are insoluble in continuous phase. Example Li et al. reported the preparation of narrowly distributed nanogels by two-stages dispersion polymerization. First, the core particles composed of PNIPAM were synthesized and then the core particles were used as nuclei in the following stage for subsequent shell addition of poly(4-vinylpyridine) (P4VP)(四乙烯基吡啶). 3.3 Other techniques to prepare core–shell polymers Example one three-step synthesis approach was used to prepare thermoresponsive CSP by Xiao et al. A single-molecular particle of hyperbranched conjugated polyelectrolyte (HCPE) was synthesized by Pu et al. Example two Fig. 9 shows a schematic illustration of the synthesis routes of single-molecular nano-particles multi-HPBPEA-g-PNIPAM Three-step synthesis approach was used to prepare thermoresponsive CSP by Cai and Liu to synthesize a novel single-molecular/unimolecular nanoparticle, multi hyperbranched poly[2-((2-bromopropionyl)oxy) ethyl acrylate)-g-poly ( Nisopropylacrylamide ] (HPBPEA-g-PNIPAM), via atom transfer radical polymerization (ATRP). Mu et al. prepared a monodisperse and multilayer core–shell (MMLCS) via surface cross-linking emulsion polymerization. Example three Fig. 10 shows the preparation of multilayer core–shell (MMLCS) emulsion via surface cross-linking emulsion polymerization. The PBA core was synthesized by seed polymerization using the PBA seed at 75± 2℃ for 3.5 h. GMA:甲基丙烯酸缩水甘油酯BA：丁基丙烯酸酯 Example four Thermosensitive PSt–PNIPAM core–shell particles were synthesized using photoemulsion polymerization technique. This new synthesis strategy may Produce a thermosensitive shell of PNIPAM networks with more homogeneous cross-linking density. Example five 5 mol% NIPAM Kim