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This manuscript represents a second part to the investigation of multiblock disulfonated poly(arylene ether sulfone) and poly(arylene ether nitrile) copolymers. In Part 1 it was shown that the multiblock copolymers had high ion exchange capacities (IECs), phase separation, strong membrane integrity and moderate water uptake. In this second part, the electrochemical properties of the membranes are...
Hyperbranched polyethylenimine (HPEI) was modified with glycidol, resulting in hydroxyl terminated HPEI (HPEI-OH). Subsequently, HPEI-OH was used as the macroinitiator to initiate the anionic ring-opening polymerization of glycidol, realizing the hyperbranched grafting copolymer with HPEI as core and hyperbranched polyglycerol (HPG) as shell (HPEI-g-HPG) through the 'grafting from' method. The diagrams...
Melt-crystallization of syndiotactic polystyrene (sPS) is studied using simultaneous small/wide angle X-ray scattering (SAXS/WAXS). Emergence, intensification, and saturation of WAXS reflections within 120 s at isothermal crystallization temperature Tc = 250 °C after quenching from 300 °C illustrate crystallinity development through successive nucleation of instantaneously stabilized crystallites...
In this study, we report a unique two-step approach to prepare pure and well-organized 10,12-pentacosadiynoic acid (DA)/melamine (MA) cocrystals, from which the topochemically polymerized product, poly(10,12-pentacosadiynoic acid) (PDA)/MA cocrystals, demonstrated reversible thermochromism (note that PDA in its pure crystalline form is thermochromically irreversible). In the first step, co-assembling...
High temperature triggered multiple-shape memory poly(benzoxazole-co-imide)s with adjustable properties were prepared via facile random copolymerization 3,3′,4,4′-biphenyltetracarbolylic dianhydride (BPDA) with two different diamine of 4,4′-oxydianiline (ODA) and 5-amino-2-(4-aminobenzene) benzoxazole (BOA). The effect of polybenzoxazole on the molecular packing, physical properties and shape memory...
Modification of membranes to improve gas separation properties has been of considerable interest. Crosslinking is one route to modify membranes, but such studies need to be performed on thin membranes to quantify the impact of such modifications at thicknesses relevant to industrial membranes. In this study, the influences of UV irradiation and physical aging on O2 and N2 gas permeation properties...
The amino groups of hyperbranched polyethylenimine (HPEI) were partially modified with isobutyric anhydride to introduce isobutyramide (IBAm) groups to HPEI, resulting in an LCST-type thermoresponsive HPEI-IBAm that is positively-charged or neutral depending on the media pH. Succinic acid (SA) units were further introduced to HPEI-IBAm through acylation with succinic anhydride, resulting in the hyperbranched...
A monomer, 2-(isobutyramido)-3-methylbutyl methacrylate (IMMA) was synthesized through a two-step reaction. When a few of IMMA (less than 4 mol%) was copolymerized with N-vinylimidazole (VIm) under free radical polymerization condition, water-soluble P(VIm-co-IMMA) copolymers were obtained. Their structural information was verified and interpreted from 1H NMR, FTIR and GPC. Kinetic analyses from 1...
We employed the quantum mechanical (QM) and all-atom molecular dynamics (AAMD) simulation methods to examine the correlation between the molecular conformation and the UV–visible absorption behaviors of two-dimensional thiophene-based conjugated polymers. We focus on the effects of molecular regioselectivity and the presence of conjugated side chains. First, when the conjugated thiophenes exist only...
A series of multiblock copolymers based upon alternating segments of a hydrophilic disulfonated poly(arylene ether sulfone) and a hydrophobic fluorine-terminated poly(arylene ether benzonitrile) (6FPAEB) were synthesized and characterized for use as proton exchange membranes (PEM). The ion-exchange capacity of the block copolymers were varied by utilizing 4,4′-biphenol or hydroquinone in combination...
The influence of aliphatic acids on the phase transition temperature of thermoresponsive hyperbranched polyethylenimine possessing a large amount of isobutyramide and amine groups (HPEI-IBAm) was studied systematically. Nine saturated aliphatic acids including formic acid (C1), acetic acid (C2), n-pentanoic acid (n-C5), trimethylacetic acid (t-C5), hexanoic acid (C6), octanoic acid (C8), decanoic...
The Sn(Oct) 2 catalyzed polymerization condition of l-lactide (LLA) and racemic lactide (r-LA) using hyperbranched polyethylenimine (PEI) as the macroinitiator was optimized. Multiarm star polymers bearing PEI core and well-controlled poly(l-lactide) (PLLA) or poly(racemic lactide) (PDLLA) arms were successfully prepared under the optimized condition, including: (1) high concentration of Sn(Oct)...
Structural evolution processes of solution-cast and melt-quenched poly(9,9-di-n-hexyl- 2,7-fluorene) (PFH) were quantitatively examined using small/wide-angle X-ray scattering (SAXS/WAXS) and differential scanning calorimetry. SAXS/WAXS profiles of solution-cast PFH indicated presence of nanograins (radius of gyration R g ≈ 5 nm) of 2D-ordered β phase. Upon heating above T g , perfected...
Multiblock copolymers based on alternating segments of telechelic phenoxide terminated hydrophilic fully disulfonated poly(arylene ether sulfone) (BPS100) and decafluorobiphenyl (DFBP) terminated hydrophobic poly(arylene ether ketimine) (PEEKt), were synthesized from the hydrophilic and ketimine-protected amorphous hydrophobic telechelic oligomers by nucleophilic coupling reactions. After film formation...
Ethyl cellulose (EC), lactide (LA) and branching comonomer 2,2-bis(hydroxymethyl) butyric acid (BHB) were copolymerized in xylene using Sn(Oct) 2 as catalyst. Catalyst amount and polymerization temperature were optimized for the effective introduction of certain amount of branched polylactide (PLA) into the side chains of comb-like copolymers having EC backbone. The characterization of the...
In the Sn(Oct) 2 catalyzed bulk copolymerization of l-lactide (LLA) and a large amount of branching comonomer 2,2-bis(hydroxymethyl)butyric acid (BHB) (LLA/BHB/Sn(Oct) 2 ratio is 5:1:0.05, 135°C), low molecular weight of copolymers with inhomogeneous structure were generated. MALDI-TOF mass spectrum demonstrated that the lower molar mass fraction was dominated with the BHB homo-polycondensation...
Reduced graphene oxide (RGO)-polymer composites were prepared via π–π stacking interactions of RGO with the perylene bisimide-containing poly(glyceryl acrylate) (PBIPGA). PBIPGA was synthesized via atom transfer radical polymerization (ATRP) of solketal acrylate (SA), using bifunctional N,N′-bis{2-[2-[(2-bromo-2-methylpropanoyl)oxy]ethoxy]ethyl}perylene-3,4,9,10-tetracarboxylic acid bisimide (PBI-Br)...
A series of novel blue light-emitting copolymers PCC-1, PCC-2, and PCC-3, composed of different ratios of electron-withdrawing segments (spirobifluorene substituted with cyanophenyl groups) and electron-donating segments (carbazole-triphenylamines), has been synthesized and characterized. In order to investigate the effect of hole/electron charge transporting segments, two reference polymers PSF and...
Syndiotactic polystyrene (sPS) composites filled with well-dispersed carbon nanocapsules (CNC) were prepared through solution blending along with ultrasonication. Several analytic techniques, including DSC, FTIR, PLM, WAXD, TEM, and TGA were performed to reveal the CNC effects on the crystallization, morphology and the thermal degradation of the as-prepared sPS/CNC composites. Addition of CNC was...
The double melting behavior of syndiotactic polystyrene (sPS) with β′-form crystallites was systematically investigated by several analytical techniques, including differential scanning calorimetry (DSC), polarized light microscopy (PLM), transmission electron microscopy (TEM), as well as wide-angle and small-angle X-ray scattering (WAXD, SAXS). For preventing the possible chain re-organization during...
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