| As one of nature’s most abundant materials, cellulose is biodegradable, biocompatibility, abundant, inexhaustible and inexpensive resources in nature, grafting thermo-reponse polymer side chain copolymerization on the cellulose carbon skeleton is one of the most effective and useful method of research hotspot in the field of science. In homogeneous system by electron transfer reaction catalyst atom transfer radical polymerization(AGET ATRP) a new thermo-reponse polymer was synthesized and its structure and thermo-reponse were characterized and analyzed.(1)Comparison of 1-allyl-3-methyl imidazole chloride salt [AMIM]C1 and 1-butyl-3-methyl imidazole chloride salt [BMIM]Cl it has found that [AMIM]Cl has a stronger ability to dissolve cellulose. Without using any catalysts through using 2-bromine propionyl bromide got cellulose-Br, FT-IR and 1H-NMR for analysis and characterization of its structure, it prove that cellulose-Br has been synthesised successfully.(2)Different ratio of NIPAAM and cellulose-Br in different reaction medium to graft, FT-IR, 1H-NMR and 13C-NMR show that the products of cellulose-g-PNIPAAM has been sythesised successfully.The grafting efficiency was increased with the increase of reaction time and the proportion of water in reaction solvent; GPC shows that the polymer molecular weight distribution at around 2.0, shows that the reaction can be controlled;Comparing the TGA of cellulose, cellulose-Br, cellulose-g-PNIPAAM and PNIPAAM, the thermal stability of cellulose-g-PNIPAAM is more stable; The TEM and UV shows that the polymer has a different shape at different temperature, when higher than polymers’ LCST, the polymer turns spherical and has a trend of aggregation and the average diameter of polymer is about 40 nm. |
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