Study On Heat-induced Spin Transition Polymethyl Methacrylate (PMMA) Composites

Polymers were applied to modify complexes with spin crossover properties through chemical and physical methods so as to improve their magnetic properties and process ability. Accordingly, spin crossover material is promising to use as information storage material. FTIR, XRD,1HNMR were used to characterize the structure of polymers and composites. DSC and SQUID were used to test the spin-transition property of complex. The main content of this dissertation is as follows:1 We introduced the structure of spin crossover complexes and study on the progress in application. We also reviewed spin-transition complex materials from the spin-transition mechanism. Measurements of the complex then reviewed in terms of its potential application of information storage material.2 Synthesizing novel complexes by means of polymer-based ligands. Initiator propionamide was synthesized thought 4-amino -1,2,4-triazole and 2-bromoisobutyryl bromine, CuCl/2,2-bipyridine as catalytic system, and N,N-Dimethylformamide as solvent, polymethyl methacrylate was synthesized by atom transfer radical polymerization (ATRP). And then the complex material was received through self-assembly reaction between polymer-based ligands and ferrous salts. However the XRD?DSC testing results show that the novel spin crossover complex perform poor transformation process at a lower temperature.3 Synthesizing novel complexes by means of polymer-based ligands. With 2-bromo-propionate as initiator, CuCl/N,N,N',N",N"-Pentamethyldiethylene-triamine as catalytic system, and N,N-Dimethylformamide as solvent, poly (glyceryl methacrylate) was synthesized by atom transfer radical polymerization (ATRP). Polymer-based ligands were synthesized by Ring-opening reaction between amino group and epoxy group, and then the complex material was received through self-assembly reaction between polymer-based ligands and ferrous salts. Polymers and complexes were characterized by FTIR,1HNMR. Moreover, the testing results of XRD and SQUID show that the new complexes have significant process of spin crossover.4 Preparing spin crossover composites with excellent process ability through physical blending. Spin crossover composites were received by the physically blending of Polymethyl methacrylate and spin crossover complexes. Polymers and composites were characterized by FTIR,1HNMR and XRD. The spin crossover property of complex was tested by DSC.