Serwis Infona wykorzystuje pliki cookies (ciasteczka). Są to wartości tekstowe, zapamiętywane przez przeglądarkę na urządzeniu użytkownika. Nasz serwis ma dostęp do tych wartości oraz wykorzystuje je do zapamiętania danych dotyczących użytkownika, takich jak np. ustawienia (typu widok ekranu, wybór języka interfejsu), zapamiętanie zalogowania. Korzystanie z serwisu Infona oznacza zgodę na zapis informacji i ich wykorzystanie dla celów korzytania z serwisu. Więcej informacji można znaleźć w Polityce prywatności oraz Regulaminie serwisu. Zamknięcie tego okienka potwierdza zapoznanie się z informacją o plikach cookies, akceptację polityki prywatności i regulaminu oraz sposobu wykorzystywania plików cookies w serwisie. Możesz zmienić ustawienia obsługi cookies w swojej przeglądarce.
Chiral poly(ferrocenyl-Schiff Bases) iron(II) complexes (CPSC)/Reduced graphene oxide (RGO) composites with excellent microwave absorption properties have been successfully prepared. The structures of poly(ferrocenyl-Schiff Bases) and their iron(II) complexes were characterized with IR, MS, HNMR, GPC, elemental analysis, etc. The morphology of CPSC and their composite materials were studied through...
The influence of aspect ratio of multiwalled carbon nanotube (MWCNTs) on rheological and electrical properties of MWCNT/polypropylene (PP) composites has been studied. Owing to the pre-grinding for MWCNTs and the efficient twin-extruder mixing, the dispersion of MWCNTs of different aspect ratios in the PP matrix is all uniform and homogeneous. With incorporation of 10 wt% MWCNTs with an aspect ratio...
The styrene (St) assisted melt grafting of glycidyl methacrylate (GMA) on polyolefin was carried out by Haake mixer, and the grafting mechanism was investigated and reconsidered. It was revealed that there is equilibrium of grafting of GMA and depolymerization of grafted PGMA chains in the GMA/polyolefin grafting process, which was affected by both of the temperature and GMA concentration. It was...
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...
Non-isothermal crystallization process of polyoxymethylene (POM) from the melts was studied by two-dimensional correlation infrared spectroscopy. A hybrid structure of FCC (1135 cm −1 ) and ECC (904 cm −1 ) during the crystallization from the molten state was found. Non-isothermal kinetics of POM crystallization was also investigated using DSC curves. A newly perturbation-correlation...
The re-assembly behaviors of spherical micelles of the polystyrene-b-poly(acrylic acid) (PS-b-PAA) diblock copolymer in different solvent mixtures were investigated using dynamic light scattering, transmission electron microscopy and atomic force microscopy. Depending on the nature of the solvent, PS-b-PAA micelles re-assembled from spheres to nanorings in toluene or to necklace-like aggregates in...
Focusing on the binary polymer mixture films under the off-critical condition, the phase dynamics and wetting layer formation mechanisms of pattern-directed phase separation are numerically investigated. The simulated results demonstrate that, for different compositions, the polymer mixtures on the strip patterned surface can exhibit various phase morphologies in the strips of the bulk, which can...
Dibenzylidene sorbitol (DBS) exists in the form of fibril and usually acts as an effective nucleating agent to facilitate crystallization of polyolefin during manufacturing. In this research, the isothermal crystallization of isotactic polypropylene (iPP) containing different amounts of DBS was followed by dynamic rheometry, and described upon a viewpoint of viscoelastic property evolution. Since...
The dissipative particle dynamics (DPD) simulation method has been used to study mesophase formation of the binary UHMWPE/PP and ternary UHMWPE/PP/PEG blends. The effects of shear rates and volume fractions of each of the blend components on end-to-end distances of UHMWPE, diffusivities and mesoscale morphologies of the blends have been investigated in detail. As compositions of the UHMWPE/PP and...
Novel star-shaped copolymers, comprised of a thermo-sensitive poly(N-isopropylacrylamide) (PNIPAAm) segment and three hydrophobic poly(ɛ-caprolactone) (PCL) arms were fabricated. The copolymers were prepared by stannous octoate (Sn(Oct) 2 ) catalyzed ring-opening polymerization of ɛ-caprolactone (CL) using cholic acid functionalized PNIPAAm as the macroinitiator. The lower critical solution...
Aqueous solutions of a blend consisting of a PEO–PPO–PEO triblock copolymer, Pluronic F127 (EO 100 –PO 65 –EO 100 ) and a PPO–PEO–PPO triblock copolymer, Pluronic-R 25R4 (PO 19 –EO 33 –PO 19 ) were studied. Thermoreversible micellization and gelation properties of the blend were examined as a function of temperature and molar ratio of 25R4 to F127 by...
New types of polyfluorene derivatives containing Ir complexes and carbazole/1,3,4-oxadiazole dendrons on the side chain have been synthesized through “click chemistry” efficiently. By introducing propargyl group into the binaphthyl unit on the polyfluorene backbone, different Ir complex- and functional dendron-containing azides could be quantitatively clicked into the main chain through the Cu(I)-catalyzed...
Poly(butylene adipate) (PBA) has been reported to have polymorphic crystal structures and only the mixture of two crystal modifications (α and β crystals) forms banded spherulites. However, how the two crystals coexist in banded spherulites remains to be solved. In this work, the morphological structure of PBA banded spherulites was analyzed from their biodegradation behavior by means of polarized...
The crystallization morphology and the melting behavior of the phase-separating poly(ɛ-caprolactone) (PCL) and poly(ethylene oxide) (PEO) blends were studied using atomic force microscopy. Two blends consisting of PCL and PEO with weight ratios of 10/90 and 90/10 were prepared to form the isolated spherical domains by the phase-separating process. The results show that the melting temperatures of...
As a continuation of our previous works on exploring shear-induced epitaxial crystallization of polyolefin blends during practical molding processing [Na et al. Polymer 2005; 46, 819 and 5258], the present study focused on the importance of molecular weight on the formation of epitaxial structure in injection-molded bars of high-density polyethylene (HDPE)/isotactic polypropylene (iPP) blends. By...
The growth behavior of the rod-like α-form crystals from both the liquid crystal and the isotropic melt state was studied in situ and in real time using a hot-stage atomic force microscopy. The growth rate and direction of the poly(9,9-dioctylfluorene) (PFO) α-form crystals are greatly affected by the orientation of the polymer chains in the liquid crystal matrix. The pre-existence of chain alignment...
[(BA-C8) 18 –(6FBA)] n was synthesized by condensation polymerization of poly(bisphenol A-co-octane) containing 18 repeat units with bromine end groups, (Br–(BA-C8) 18 –Br), and 4,4′-(hexafluoroisopropylidene)diphenol (6FBA). This copolymer was confirmed to be semicrystalline after a single melting temperature was detected by differential scanning calorimetry. The changes in...
The effects of an anionic surfactant, sodium dodecyl sulphate (SDS), on the optical transmittance, thermal, and rheological properties of methylcellulose (MC) aqueous solutions have been studied. The particular interest of this work was focused on the effects of SDS on the sol–gel transition of MC. Basically, two effects of SDS have been identified, which are the salt-out and salt-in effects at low...
The influence of stem conformation on the crystallization of i-PP is studied by growing α-form lamellae in melts of β-form lamellae at different temperatures. The melting of β-form lamellae and the crystallization of α-form lamellae is observed in situ at the interface of α- and β-form spherulites by AFM. The growth rate of α-form lamellae in the melt of β-form lamellae is much lower than that in...
Podaj zakres dat dla filtrowania wyświetlonych wyników. Możesz podać datę początkową, końcową lub obie daty. Daty możesz wpisać ręcznie lub wybrać za pomocą kalendarza.