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In this paper, amphiphilic biodegradable methoxy-poly(ethylene glycol)-poly(l-histidine)-poly(l-lactide) (mPEG–PH–PLLA) triblock copolymers with pH sensitivity were synthesized. The properties of mPEG–PH–PLLA triblock copolymers were investigated by GPC, 1 H NMR, DSC, TGA, XRD and polarized optical microscopy. The results showed that the thermal properties of the triblock copolymers varied...
Atomistic and coarse-grained (CG) models of cross-linked sulfonated Poly (1, 3-cyclohexadiene) (xsPCHD) were developed and implemented in Molecular Dynamics (MD) simulations of PCHD chains with different architectures. In the atomistic model, PCHD chains are cross linked by a sulfur–sulfur bond. Sulfonic acid groups are evenly distributed along the chain. The architecture is specifically aimed for...
For the preparation of block copolymers containing polyfluorene (PF) and hole transporting segment, PF homopolymers with diphenylamine terminals were synthesized by Suzuki coupling polymerization. The terminals of PF were converted to polytriphenylamine (PTPA) block by C–N coupling polymerization to give PTPA-block-PF-block-PTPA (PF-PTPA) triblock copolymers with different PTPA chain lengths. These...
A facile and objective method is introduced to automatically quantify the filler dispersion in polymer composites through image analysis. This method consists of automatic identification of the fillers in the image and a rigorous measurement of the filler dispersion within the space of functions. Compared with previous methods, this method has the advantages of 1) automatically recognizing the fillers,...
Plasticizing effects of water and glycerol are widely used in pharmaceutical applications of gelatin films. We investigated gelatin films containing water or water and glycerol equilibrated under a range of relative humidity. Films were characterized by differential scanning calorimetry running in classical and modulated modes. Glass and melting transition temperatures, relaxation and melting enthalpies...
We reported the design of a grape-cluster-like conductive network in a polypropylene (PP) matrix, where oriented multi-walled carbon nanotubes (MWCNTs) served as branches and provided charge transport over large distances while grape-like carbon black (CB) aggregates enriched around MWCNTs and linked these conductive tubes through charge transport over small distances. The key for construction of...
Two donor–acceptor conjugated polymers PCTBTC8 and PCTTBTC12 have been prepared from Suzuki coupling reactions between the 2,7-carbazole and alkoxy substituted 2,1,3-benzothiadiazole units with two different linker groups thiophene and thieno[3,2-b] thiophene, respectively. The polymer PCTTBTC12 with the thieno thiophene linker group possessed a red-shifted UV-vis absorption spectrum and similar HOMO...
Disulfonated poly(arylene ether sulfone)s are high glass transition temperature polymers, and their water and salt transport properties depend sensitively on thermal processing history. In this study, films of a 32 mol% disulfonated poly(arylene ether sulfone) random copolymer (BPS-32), polymerized in the potassium counter-ion form, were acidified using solid state and solution routes. The resulting...
Micelles of a new amphiphilic copolymer bearing pendant thymine groups, polystyrene-co-poly (N-acryloylthymine) (PS-co-PAT), were prepared in aqueous solutions. Transmission electron microscopy and laser light-scattering studies showed that the resultant spherical micelles were nanoscale with narrow size distribution. Moreover, ratio of hydrophilic and hydrophobic contents strongly influenced the...
Two novel conjugated alternating copolymers with [1,2,5]thiadiazolo[3,4-f]benzotriazole as acceptor and 9,9-dioctylfluorene or N-9’-heptadecanyl-carbazole as donors respectively, were synthesized by Suzuki polycondensation. Both of the two copolymers have nearly ideal band gaps and show excellent absorption spectra in near infrared region. Polymer solar cells based on the blends of them and [6,6]-phenyl-C...
In-situ synchrotron small-angle X-ray scattering (SAXS) and wide-angle X-ray scattering (WAXS) were carried out to investigate the uniaxial drawing-induced deformation and structure transitions of β form isotactic polypropylene (iPP) at varying temperatures (30 °C, 60 °C, 80 °C, 100 °C and 120 °C). The WAXS results indicated that the initial strain for the strain-induced β–α transformation decreases...
Conventional free radical copolymerization of 9-vinylbenzyladenine (VBA) and 2-(dimethylamino)ethyl methacrylate (DMAEMA) with subsequent protonation afforded the synthesis of adenine-containing polyelectrolytes. All adenine-containing polyelectrolytes exhibited classical polyelectrolyte solution rheological behavior with scaling factors near 0.6 and 1.6 in the semidilute unentangled and semidilute...
A novel dual-responsive core-shell type hybrid inclusion complex composed of an azobenzene-terminated copolymer PNIPAM-b-PAA and β-cyclodextrin-modified silver/polydiacetylene (β-CD@Ag/PDA) nanocrystals had been fabricated based on the host-guest interaction between azobenzene unit in the block copolymer and β-CD cavities on the surface of the hybrid nanocrystals. While the hybrid nanocrystals provide...
A series of isotactic polypropylene/poly(propylene-1-octene) (iPP/PPOc) in-reactor alloys were synthesized by a one-step polymerization process, using Metallocene/Ziegler–Natta hybrid catalyst. The alloys were characterized by FT-IR, DSC, optical microscopy and SEM. The results suggested that the spherical morphology was maintained during one-step polymerization process, which provided a potential...
Design, synthesis, morphology, mechanical properties and in vitro oxidative stability of new class of surface modified thermoplastic elastomers containing mixed soft rubbery poly(n-butyl acrylate-b-dimethylsiloxane-b-n-butyl acrylate) (PnBA-b-PDMS-b-PnBA) block and glassy poly methyl methacrylate (PMMA) end blocks have been reported. Thus well-defined pentablock copolymers such as PMMA-b-PnBA-b-PDMS-b-PnBA-b-PMMA...
This paper expounds a revised characterisation of the elastic stresses ahead of a crack tip in polycarbonate which takes account of the elastic–plastic boundary stresses induced by the presence of the crazed region that surrounds a crack. The advanced experimental techniques used in this work have provided insights into fractography, identification of the crazed region and location of the crack tip...
Poly(epsilon-caprolactone) (PCL) nanocomposites containing carbon nanotubes, layered silicates, sepiolite or polyhedral oligomeric silsesquioxane (POSS) were characterized by advanced thermal analysis. Adding carbon nanotubes or layered silicates increases the excess heat capacity in quasi-isothermal crystallization experiments by MTDSC, pointing to an increased fraction of reversibly melting and...
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