Design And Synthesis Of Novel Functional Schiff-Based Polymers

Schiff base complexes and Schiff-based polymers have attracted attention by many chemist and material expert owing to their unique photochromic, thermochromic properties and wide application in luminescent materials, liquid crystal materials, structural materials, nonlinear optical materials, catalyst. In this dissertation, basing on molecular designs, two functional blocks such as perylene bisimide and pyrazolone were introduced to the polymer structures,trying to obtain two novel Schiff-based polymers, whose optical property and electrical property are more excellent and the inherent properties of Schiff-based polymers will be kept.(1) In this paper, two intermediate compounds: N,N'-di(3-aminobenzol)-1,6,7,12- tetra-(4-tert-octylpheoxy)-perylene-3,4,9,10-tetracarboxylic acid bisimide and 2,5-Bis (lauryloxy)benzene-1,4-dialdehyde were prepared and their structures were confirmed. The synthesis conditions were discussed preliminary. Then, polymerⅠhas been synthesized by solution polycondensation reactions using metacresol as solvent. Comparing different technical conditions, polymerization degree of the polymer was found only 1-2, and highter molecular weight polymer cannot be obtained. This may be attributed to the main chain in the designed Schiff-based polymerⅠis too rigid, while N,N'-di(3-aminobenzol)-1,6,7,12-tetra-(4-tert-octylpheoxy)–perylene-3,4,9,10-tetracar boxylic acid bisimide has a limited solubility. So, it is difficult to obtain highter molecular weight polymer. In addition, the structure of the polymerⅠis unstable.(2) Basing on molecular designs, 1,6-bis(1',3'-diphenyl-5'-pyrazolone-4'-yl)-1,6- hexanedione was synthesized. Then, polymerⅡandⅢwere synthesized by polycondensation reactions of 1,6-bis(1',3'-diphenyl-5'-pyrazolone-4'-yl)-1,6-hexane- dione with 1,6-Diaminohexane and compound 13. The HNMR data shows polymerⅡwas decomposited in non-protonic solvent, such as DMSO and DMF. The chemical modificated polymerⅢhas good solubility and can be dissolved in a variety of organic solvents and the TG data shows polymerⅢhas good thermal stability.(3) Starting from 1,4,5,8-naphthalene teracarboxylic acid, 1-butyl bromide and 1-octane bromide, two novel compounds 1,4,5,8-tetra-(4-n-butoxy-carbonyl)- naph thalene and 1,4,5,8-tetra-(8-n-octoxy-carbonyl)-naphthalene were prepared by using tetraoctane-ammonium bromide as phase transfer catalyst. Their chemical structures were comfirmed by HNMR and FTIR, and their thermal properties were inverstigeted by polarization microscopy and DSC. Their UV-Vis and fluorescent spectrum properties were studied and the spectroscopic properties of the two compounds were found very similar, and the length of introduced alkyls bring little influence to spectroscopic properties of the two compounds.