Synthesis,Characterization Of Pseudo(Poly)Rotaxanes And Studies Of The Properties-Supramolecular Seil-Assembly Of Cucurbituril [6] With (Poly) Electrolyte

Supramolecular chemistry based on the theory of non-covalent bonds has received much attention in recent years not only because it is a cross-subject of chemistry, life science, molecular electronics and material science but also because of their unique structures and unusual properties different from those of conventional covalent polymers. (Poly)rotaxane which is a branch of supramolecular chemistry is combined by host molecules (cyclodextrins, crown ethers, calixarene, cucurbiturils) and guest molecules. (Poly)rotaxane has received much attention because the potential use such as a material for molecular devices, molecular machine and catalyst.Cucurbituril[6] (CB[6]) , which is a macrocycle comprising six glycoluril units interconnected with twelve methylene bridges, has a hydrophobic cavity that is accessible through two identical carbonyl-fringed portals. CB[6] has been attracting much attention not only because of easy synthesis from glycoluril and formaldehyde, highly symmetric structure and high chemical and thermal stability, but also because of the polar carbonyl groups at the portals and a hydrophobic cavity allow it to form stable host-guest complexes with small molecules such as protonated aminoalkanes, diaminoalkanes (K>10~5) through the formation of (pseudo)rotaxane. Molecular switch, molecular machine based on pseudorotaxane containing CB[6] and CB[6] using as catalyst have been reported. Also, polyrotaxanes, molecular necklace and rotaxanedendrimer containing CB[6] have been synthesized. But side-chain (pseudo)polyrotaxanes containing CB[6] as a molecular bead have been scarcely reported .This paper reports the synthesis of three new series of pseudo(poly)rotaxanes by supramolecular self-assembly of CB[6] (host molecule) with (poly)viologen, (poly)amine, polypyridinium (guest molecules) in water at room temperature. And the chemical structure and properties of these pseudo(poly)rotaxane were confirmed and researched. This paper has three parts as following:1. Pseudo(poly)rotaxanes containing CB[6] and (poly)viologenIn this part, we synthesized three pseudo(poly)rotaxanes: pseudopolyrotaxanes (PPeVCB) containing polypentamethyleneviologen (PPeV), pseudorotaxane (BVCB) containing H-butyl viologen (BV) and pseudorotaxane (4VBVBuCB) containing Ar-vinylbenzyl-Ar'-butyl-4,4' -bipyridinium (4VBVBu). The chemical structures of PPeVCB, BVCB and 4VBVBuCB were confirmed by 'H NMR, elemental analysis, IR and MS. CB[6] beads are localized aliphatic chain and combine N+ of violegen by non-covalent bonds. In BVCB, the molar ratio of CB[6] to BV is 2:1. The properties of these pseudo(poly)rotaxanes were researched by thermogravimetry analysis (TGA), X-ray powder diffraction (XRD), UV-vis, environment scanning electron microscope (ESEM), fluorescence analysis, chemical reduction and effect of salts. The results show that pseudo(poly)rotaxanes have higher thermal stability, stronger absorption band and higher oxidation ability than the parent (poly)viologen. We get the copolymers by copolymerization of 4VBVBuCB and methylacrylamide (MAM) at different molar ratio, and the properties of the copolymers were researched with TG and UV-Vis.2. Pseudo(poly)rotaxanes containing CB{6] and (poly)aminesIn this part, we prepared a novel side-chain pseudopolyrotaxanes(PVBDACCB) based on polyamines (poly-/V'-(4-vinylbenzyl)-l,4-diaminobutane dihydrochloride, PVBDAC). A unique feature of the pseudopolyrotaxanes is that the degree of threading (number of CB[6] beads per repeat unit) can be controlled from 0 to 1.0 by controlling the amount of CB[6] added. Also, we synthesized a pseudorotaxane (VBDACCB) monomer containing Ar'-(4-vinylbenzyl)-l,4- diaminobutane dihydrochloride (VBDAC) and got the homopolymer (PVBCB) by homopolymeration of VBDAC and the copolymers by copolymerization of VBDACCB and MAM at different molar ratioo The chemical structures of these pseudo(poly)rotaxanes were confirmed by 'H NMR, 13C NMR, elemental analysis, IR and MS. The results show that the CB[6] beads are localized tetramethylene units. The properties of these pseudo (poly)rotaxanes were researched by TGA, XRD, ESEM and effect of salts. The PVBDACCB has higher thermal stability and chain regularity than the parent polyamine salts, and the decomposition temperature and chain regularity increase with increasing amount of CB[6] threaded. The effect of salts to PVBDACCB is studied by the transmittance with UV-vis, and the result shows the Nal is the satisfied precipitant to PVBDACCB.3. Pseudopolyrotaxanes containing CB[6] and polypyridiniumIn this part, we prepared three pseudopolyrotaxanes (P4VBuBrCB, QP4VPBuCB, QP4VPHxPCB) based on poly(4-vinyl,A?-?-buty pyridinium bromide) (P4VBuBr) or quaternized poly-4-vinylpyridine derivative (QP4VPBu, QP4VPHxP) which were synthesized by reacting 4-vinylpyridine with 1-bromobutane or Af-(6-bromide)-/7-butyl -pyridinium. The chemical structures of the pseudopolyrotaxanes were confirmed by 'H NMR, IR and elemental analysis. The CB[6] beads are located on the aliphatic chain of the polymer. The properties of these pseudo(poly)-rotaxanes were researched by TGA, XRD, UV-Vis, effect of salts and viscosity. The pseudopolyrotaxanes have higher thermal stability and intensity of absorption band than the parent polymer. In P4VBuBrCB andQP4VPBuCB, the degree of threading can only reach 27.8% and 21.7%. While in QP4VPHxPCB which has high molecular weight, the degree of threading (q/n, the average number of CB[6] beads per repeat recognition unit of QP4VPHxP) can be controlled from 0.2 to 1.0 by controlling the amount of CB[6] added. Compared with the parent polymer QP4VPHxP, QP4VPHxPCB have lower intrinsic viscosity which is attributed to the more coiled conformation of the backbone and smaller change with the change of the concentration or temperature which is consistent with the hydrodynamic radius and more rigid chain conformation because of the threaded CB[6].This paper synthesized viologen pseudopolyrotaxanes in which the molar ratio of host (CB[6]) to guest (BV) was 2:1 for the first time; firstly prepared the side-chain pseudopolyrotaxanes (PVBDACCB and QP4VPHxPCB) in which the degree of threading could be controlled from 0 to 1.0 by controlling the amount of CB[6] added, especially the QP4VPHxPCB having high molecular weight which was not reported; we researched the effect of inorginc salt to the solution of pseudopolyrotaxanes for the first time; from the compare of the properties between pseudo(poly)rotaxanes and the parent compounds, we found pseudo(poly)rotaxanes had preferable properties, so CB[6] cound be used as a modifier.