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A series of efficient and spectrally stable blue light-emitting polyfluorene derivatives containing 3,7-dibenzothiophene-S,S-dioxide (SO) unit in main chain and oxadiazole (OXD) moiety in the side chain were synthesized via Suzuki copolymerization. It was realized that the glass transition temperatures of the resulted copolymers PFSO-OXD increased gradually with the content of OXD, while the UV-vis...
Optically active polyurethanes (LPU and DPU) and racemic polyurethane (RPU) were synthesized by the self-polyaddition of the isocyanate-phenols which derived from the chiral and racemic tyrosine. All of the polymers were characterized by FT-IR, 1 H NMR, GPC, UV–Vis spectroscopy, circular dichroism (CD) spectroscopy, TGA and X-ray diffraction (XRD), and the infrared emissivity values were investigated...
Two aromatic tetraketones, 4,4′-thiobis[(p-phenyleneoxy)benzil] (STK, 1) and 4,4′-thiobis[(p-phenylenesulfanyl)benzil] (3STK, 2) were synthesized by the nitro nucleophilic substituent reactions of 4-nitrobenzil and corresponding diol compounds. The two tetraketones were polymerized with three aromatic tetraamines, including 3,3′-diaminobenzidine (a), 3,3′,4,4′-tetraaminodiphenylether (b) and 3,3′,4,4′-tetraaminodiphenylsulfone...
A linear amphiphilic multiblock copolymer (PNIPAm-PtBA-PNIPAm) m was successfully synthesized by a two-step reversible addition–fragmentation transfer (RAFT) polymerization in the presence of a cyclic trithiocarbonate as RAFT agent. The micelle behavior of (PNIPAm-PtBA-PNIPAm) m multiblock copolymer in aqueous solution was then investigated by means of normal TEM, cryo-TEM, static...
Graphene nanosheets were prepared by complete oxidation of pristine graphite followed by thermal exfoliation and reduction. Polyethylene terephthalate (PET)/graphene nanocomposites were prepared by melt compounding. Transmission electron microscopy observation indicated that graphene nanosheets exhibited a uniform dispersion in PET matrix. The incorporation of graphene greatly improved the electrical...
The tensile and compressive properties of triptycene-polycarbonates were tested over 6 orders of magnitude in strain rate. Initially we studied a low molecular weight, low triptycene content PC blended with Iupilon ® PC and then a series of higher molecular weight, higher triptycene content polymers. The PC blend with only 1.9wt% triptycene displayed up to 20% increase in modulus and up to...
Polyimide/layered silicate nanocomposites were prepared via in situ polymerization process from PMDA-ODA and organo-MMT in a solution of N,N-dimethylacetamide. XRD, FTIR, UV–vis analyses showed that at the content of 1wt% MMT, MMT were well intercalated, exfoliated and dispersed in polyimide matrix. As the MMT content is more than 3wt%, MMT agglomerates became severe as shown by the transparency and...
The transient rheological behavior and morphology evolution of polymethyl methacrylate (PMMA)/polystyrene (PS) binary polymer blends with well-defined initial structure were measured in simple shear flow under isothermal conditions. The size and distribution of the dispersed phase and the composition of the blends were designed and fabricated by Computer Numerical Controlling (CNC) machining, photolithography,...
Montmorillonite (MMT)/Organo-soluble polyimide (PI) hybrids were prepared using a monomer solution intercalation polymerization method. The organo-soluble polyimide was based on pyromellitic dianhydride and 4,4′-diamino-3,3′-dimethyldiphenylmethane. The MMT was organo-modified with three types of intercalation agents: amino acids, primary aliphatic amines and quaternary ammonium salt. The dispersion...
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