Preparation And Properties Of Organic/Inorganic Hybrid Materials Via "Living" Controlling Polymerization

In 1984, Schmidt firstly brought forward the conception of organic/inorganic hybrid material. This kind of material has many advantages, such as height thermal stability, fire retardant, better mechanical behaviour, etal. The hybrid materials are becoming the research focus. This paper will do the work from three aspects: in the first, synthesizing halloysite–g–methylmethacrylate-b–styrene-b–methylmethacrylate (halloysite-g-PMMA-b-PSt-b-PMMA) triblock copolymer brushes in one step increasing-chain via RAFT. In the second, introducing methacryloxyethyltrimethy -lammonium chloride (MOETMAC) as insertion agent into MMT layer, and then preparing MMT-g-PMMA hybrid materials by RAFT. In the third, using RAFT and ATRP to prepare comb polymer grafting from silicon dioxide hybrid material such as SiO2-g-PHEMA-g-PMOETMAC SiO2-g-PHEMA-g-PSt. All above are characterized by FT-IR,GPC,TG-DTA,XRD,XPS,TEM. The main results are listed as the following.Firstly, preparing triblock-polymer grafting from halloysite hybrid material by one increasing chain step. (1) The results of FT-IR, XPS analysis indicate that halloysite-BDAAT is prepared; the patter of halloysite is successfully coated by the chain of PMMA-b-PSt-b-PMMA through TEM observation. (2) The results of TGA show that the contents on the halloysite surface increase more and more against polymerization time. The kinetic research expresses a stable radical concentration in the whole course of polymerization, and also indicates that the whole system displays some "living" characters.Secondly, BDAAT modifying MMT to prepare MMT-g-PMMA inorganic/ organic material. (1) By FT-IR, TG, XRD measurements etal, MOETMAC is sure to be inserted into the MMT layers, and then polymerize with MMA, and the structure of MMT is exploited completely. (2) By the research of reaction kinetic, the grafting rate is line with time, which suggests a good control in the reaction system. (3) The TG /DTA data of MMT-g-PMMA suggests that it has good heat-stability.Thirdly, preparing comb polymer grafting from silica dioxide. (1) FT-IR, XPS TG analysis express that PHEMA-Br is proved to be grafted to silica dioxide surface by RAFT course, and then as the ATRP initiator initiates the polymerization of the monomers such as MOETMAC, St to getting SiO2-g-PHEMA-g-PMOETMAC, SiO₂-g-PHEMA-b-PSt hybrid materials. TG/DTA curves indicate these hybrid materials have height grating rate and good heat endurance. (2) The particle size and the"Zeta"potential analysis suggest that the forth hybrid material has a rather large positive"Zeta" potential, which can easily be dispersed into water phase. (3) TEM analysis proves that these hybrid materials have the nuclear shell structure.