Preparation, Structures And Properties Of Functional Polysiloxanes With Sites For Multiple Hydrogen Bonds

Polysiloxane has various excellent properties, such as high flexibility of its main chain, low glass transition temperature, hydrophobicity, physiological inertness and outstanding thermal stability. Polysiloxane-based supramolecules, assembled through non-covalent intermolecular actions such as multiple hydrogen bonds and lanthanide-ligand interactions, keep the mechanical performance of polysiloxane and obtain reversibility and stimulative responsibility from the non-covalent interactions at the same time. The structural and morphological diversities of the supramolecules also bring them applications in different fields. So supramolecular assembly has been a research hotspot in many research fields including polymer chemistry and biomaterials. Functional polysiloxanes complex with lanthanide ions are potential materials for luminescent devices because of the prominent performance showed by the rare earth ions. Polysiloxane-based biomaterials are growingly used in clinic treatment, so more interests are focused on controlled drug release systems based on functional polysiloxane.a, ω-N, N’-diphenylmalonamide terminated polysiloxane (PMP) was prepared through hydrosilylation of2-allyl-N1, N3-diphenylmalonamide (MA) and a, ω-hydride terminated polysiloxane (HP), which was obtained through cationic polymerization. PMP showed stacked layer morphology in its SEM images, resulting from intermolecular non-covalent actions in different dimensionality. Colorful photoluminescent emissions were detected from the supramolecules assembled by PMP and various rare earth ions through lanthanide-ligand interactions. White light emitting material was obtained by coordinating two different ions at a certain ratio into PMP. The role of Si-O-Si chain in the luminescent materials based on functional polysiloxane and its contribution to their luminescent performance were determined using various measurements.Cysteine-functionalized polysiloxane (PCMS) was prepared through thiol-ene click reaction of cysteine and a, ω-vinyl terminated polymethylvinylsiloxane, which was obtained through anion polymerization. Measurements such as FT-IR and NMR were employed to detect the structure of PCMS. The drug release performance of the release system based on PCMS in environments with different pH values was measured. PCMS has distinct drug release control ability with stimulative responsibility to the change of pH value in the circumstance. The supramolecules assembled by PCMS and lanthanide ions showed also obvious luminescent emissions, but the colors of these emissions are different with those emitted by the systems based on PMP.