| Poly (N-isopropylacrylamide) (PNIPAM) is an responsive polymer which undergoes a temperature-induced, reversible phase transition at approximately 32℃. Below the lower critical solution temperature (LCST), the polymer is soluble in water because of the strong hydrogen bonding between the water molecules and the NIPAM groups. The increase of temperature will disrupt hydrogen bonds and favor hydrophobic interactions. When the temperature of the solution reaches LCST, polymer chains change from the well-dissolved coil state to the less soluble globular state.Different molecular design of PNIPAM-based polymers and structure design of PNIPAM-based colloids will bring new attributes. So the particle design and polymer design continue attracting attentions. Through some special technology, this thesis designed and prepared the functional microgel with new structure and the new block copolymer. The properties of them were measured.Numerous reports described different structures of PNIPAM-based core-shell particles with hydrophobic polymer as core and PNIPAM as shell or NIPAM copolymer as core and PNIPAM as shell. However, as much as we know, little work has been reported regarding particles with PNIPAM as the core and hydrophobic polymer as the shell. Although a study about such a particle is significant, which is helpful to research concerning restricted motions of PNIPAM chains and the drug delivery.It is difficult to prepare this kind of particles by a general seed emulsion polymerization. The problem should be that PNIPAM is the polymer with weak hydrophobicity even when it is in the collapse state. The hydrophobicity of most hydrophobic monomers, such as Styrene or MMA, is stronger than that of PNIPAM. Therefore, when the second monomer was added into system, it would enter the inner part of particles, instead of staying on the surface.We try to use microwave heating polymerization to solve this problem and obtain such particles. Compared with normal heating, microwave heating is...
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