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Two isomers of conventional cis-dicyclohexyl-3,3′,4,4′-tetracarboxylic dianhydride (4,4′-HBPDA), i.e. dicyclohexyl-2,3′,3,4′-tetracarboxylic dianhydride (3,4′-HBPDA) and dicyclohexyl-2,2′,3,3′-tetracarboxylic dianhydride (3,3′-HBPDA), were prepared through a four-step procedure. The data from single crystal X-ray diffraction revealed that 3,3′-HBPDA possessed higher structural rigidity/linearity than...
Extension induced crystallization of γ-irradiated isotactic polypropylene (γ-iPP) was studied with the combination of extensional rheology and in-situ wide-angle X-ray scattering (WAXS). The high gel content and markedly frequency-dependent storage modulus of γ-iPP indicates the occurrence of slight crosslinking accompanied by formation of free branching/dangling chains during irradiation. With WAXS,...
Anion exchange membranes (AEMs) with phase-separated morphologies were prepared by brominating poly(ether sulfone) copolymers with oligo(2, 6-dimethyl-1, 4-phenylene oxide) moieties, followed by quaternization and ion exchange. By this synthetic strategy, quaternary ammonium groups were densely and selectively introduced into oligo(phenylene oxide) moieties. Small angle X-ray scattering patterns of...
Novel partially bio-based polyimides were prepared from 2, 5-diamino-2, 5-dideoxy-1, 4: 3, 6-dianhydrosorbitol (diaminoisosorbide, DAIS) dihydrochloride, 2, 5-diamino-2, 5-dideoxy-1, 4: 3, 6-dianhydroiditol (diaminoisoidide, DAII) dihydrochloride, and various dianhydrides via a conventional one-step method in m-cresol. Inherent viscosity values of these polyimides spanned a range of 0.5–1.5 dL/g....
A series of triptycene-based porous polyimides (STPIs) were synthesized by condensation polymerizations. The structure and properties of these STPIs were characterized by IR, solid 13C NMR, powder XRD, SEM, TEM and gas absorption. As STPI-2 with the high thermal stability, they display excellent adsorption ability to CO2 uptake capacity of 14.6 wt% (273 K), and exhibit the high selectivity of CO2/N...
Substrate wetting of the component(s) of thin polymer blend films strongly dictates their phase evolution during thermal annealing. In the case of wetting by one component being preferential than the other, a continuous wetting layer at the substrate will form. Here, we report that the preferential wetting of PMMA within a PS/PMMA thin film can be prevented under normal pressure. Moreover, the external...
A series of star triptycene-based porous polymers (STPs) were synthesized from the palladium-catalyzed C–C coupling polymerization of 2, 6, 14-triiodotriptycene. The porous properties of these STPs including surface area, pore size and gas adsorption can be tuned by varying the strut length from ethynylene to phenylene to phenyleneethynylene. As STP-5, they display the BET surface area of 601 m ...
Various methods were employed to study the thermal behaviors of a novel microbial polyhydroxyalkanoate (PHA) terpolyester, namely, poly(3-hydroxybutyrate-co-3-hydroxyvalerate-co-3-hydroxyhexanoate) (PHBVHHx) compared with poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBHHx). PHBVHHx showed higher crystallization rate and degree of crystallinity. PHBVHHx exhibited also different multiple melting...
A novel injectable in situ cross-linked hydrogel has been designed via Michael type addition between thiol-modified chitosan (CS–NAC) and PEG diacrylate (PEGDA). Hydrogel was rapidly formed in situ under physiological conditions. The gelation time depended on the content of free thiols in CS–NAC, temperature, and concentration of CS–NAC and PEGDA. Thermogravimetric analysis showed the thermal stabilities...
A series of sulfonated polyimides (SPIs) were synthesized in m-cresol from 4,4′-binaphthyl-1,1′,8,8′-tetracarboxylic dianhydride (BNTDA), 4,4′-diaminodiphenylether-2,2-disulfonicacid (ODADS), and 4,4′-diamino-diphenyl ether (ODA) in the presence of triethylamine and benzoic acid. The resulted polyimides showed much better water resistance than the corresponding sulfonated polyimides from 1,4,5,8-naphthalenetetracarboxylic...
A novel sulfonated diamine monomer, 1,4-bis(4-aminophenoxy)-naphthyl-2,7-disulfonic acid (BAPNDS), was synthesized. A series of sulfonated polyimide copolymers were prepared from BAPNDS, 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTDA) and nonsulfonated diamine 4,4′-diaminodiphenyl ether (ODA). Flexible, transparent, and mechanically strong membranes were obtained. The membranes displayed slightly...
The influence of the solvent evaporation rate on the crystallization of the poly(vinylcyclohexane)-b-poly(ethylene)-b-poly(vinylcyclohexane) (PVCH–PE–PVCH) triblock copolymer with the high T g of PVCH segment in chloroform was investigated. The competition between the crystallization of PE block and the vitrification of PVCH in the triblock copolymer was controlled through changing the solvent...
This paper reports the synthesis of a novel maleimide-terminated thioetherimide oligomer and its copolymerization with reactive solvents bearing vinyl. Starting from 3-chlorophthalic anhydride and 4-chlorophthalic anhydride, 2,2′,3,3′-thiodiphenyl tertracaboxylic dianhydride (3,3′-TDPA) and 3,3′,4,4′-thiodiphenyl tertracaboxylic dianhydride (4,4′-TDPA) were synthesized. Thereby, a novel maleimide-terminated...
4,4′-Bis(3,4-dicarboxyphenylthio)diphenyl sulfone dianhydride(4,4′-PTPSDA) and 4,4′-bis(2,3-dicarboxyphenylthio)diphenyl sulfone dianhydride(3,3′-PTPSDA) were synthesized from chlorophthalic anhydrides and bis(4-mercaptophenyl)sulfone. Their structures were determined via IR spectra, 1 H NMR and elemental analysis. A series of polyimides were prepared from isomeric PTPSDAs and aromatic diamines...
A series of polyimides (PIs) based on 2,3,3',4'-benzophenonetetracarboxylic dianhydride (2,3,3',4'-BTDA) and 3,3',4,4'-BTDA were prepared by the conventional two-step process. The properties of the 2,3,3',4'-BTDA based polyimides were compared with those of polyimides prepared from 3,3',4,4'-BTDA. It was found that PIs from 2,3,3',4'-BTDA have higher glass transition temperature and better solubility...
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