The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Simultaneously improving toughness and strength without sacrificing thermal resistance and maintaining the viscosity of an epoxy resin for application in Liquid Composite Molding (LCM) process has been challenging. This paper reported such a high performance epoxy system modified by a hybrid of toughening agents, block copolymer particle (BCP) and core-shell particle (CSP), was successfully prepared...
Pd-catalysed oxidative C–H/C–H coupling homopolymerization of thiazole derivatives with different numbers (n = 1–3) of thiophene as bridged units was described. It represents a facile and practical methodology to prepare thiazole-based conjugated polymers in excellent yields. Three conjugated polythiazole derivatives (P1–P3) were synthesized by utilization of ligand-free Pd(OAc)2 as a catalyst in...
The vital role of chain ends in the crystallization of linear polymers can be understood by unraveling the mechanisms of crystallization of cyclic polymers. A commercial chip-calorimeter Flash DSC1 was employed to compare the nucleation and overall crystallization rates between linear and cyclic poly(epsilon-caprolactones) (PCL) with similar molar masses of around 2 kg/mol. In the high temperature...
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...
We studied the power-law heating-rate dependence of superheating for the melting of alpha- and beta-crystals of isotactic polypropylene by means of chip-calorimeter, and expanded our parallel observation to higher heating rates by means of molecular simulations. We observed that, at low heating rates, the melting of lamellar crystals after thickened via melting-recrystallization exhibits no power-law-dependent...
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 ...
Poly(ε-caprolactone)-block-poly[2-(dimethylamino)ethyl methacrylate] (PCL-b-PDMAEMA) block copolymers were applied to fabricate elongated polymer platelets with axial length of 5–20 μm and thickness of ca. 10 nm by crystallization-driven self-assembly (CDSA). The block copolymer platelets composed of a crystallized PCL layer sandwiched between two PDMAEMA layers were obtained spontaneously by adding...
Two series of benzoxazine (BOZ) based composites were prepared with graphene oxide (GO) and graphite via in situ intercalative polymerization. Based on isothermal and non-isothermal mode Differential Scanning Calorimetry results, BOZ with the addition of GO could not only decrease the cure temperature, but also increase the cure rate of BOZ. On the contrary, BOZ with the addition of graphite would...
Biodegradable polyrotaxane (PR)-based triblock copolymers were synthesized via the atom transfer radical polymerization (ATRP) of N-isopropylacrylamide (NIPAAm) initiated with polypseudorotaxanes (PPRs) consisting of a distal 2-bromopropiomyl bromide end-capping poly(ε-caprolactone) (Br-PCL-Br) and a varying amount of α-cyclodextrins (α-CDs) in the presence of Cu(I)Br/PMDETA at 25 °C in aqueous solution...
It was reported that polyrotaxanes (PRs) comprising β-cyclodextrins (β-CDs) and Pluronic F127 end-capped with poly(N-isopropylacrylamide) blocks show a β-CD aggregated state in which the threaded β-CDs are self-aggregated into a typical channel-type crystal structure after water incubation. At the same time, they converse into a β-CD dispersed state in which the entrapped β-CDs are randomly dispersed...
CdTe/PEDOT-PSS hybrid microspheres have been attained via the direct polymerization of EDOT-PSS on mercapopropionic acid capped CdTe quantum dot aggregates. The obtained hybrid microspheres provide multiple-color absorption and emission properties as a function of the pH value of the medium, which indicate the presence of both physical and electronic contact between the PEDOT and CdTe. The pH-dependent...
Herein novel polyrotaxanes (PRs) comprising γ-CDs and Pluronic F127 end-capped using poly(N-isopropylacrylamide) blocks were prepared via the atom transfer radical polymerization in aqueous medium at room temperature. The structure was characterized in detail by 1 H NMR, 2D NOESY NMR, FTIR, GPC, WXRD and DSC analyses. Solvent treatments were conducted on the resulting PRs via incubation in...
Crystallization and melting of a poly(ethylene oxide) (PEO) diblock copolymer containing a tablet-like block of poly{2,5-bis[(4-methoxyphenyl)oxycarbonyl]styrene} (PMPCS) in ultrathin films have been studied using atomic force microscopy (AFM) coupled with a hot stage. The PEO and PMPCS block possess the number-average molecular weights (M n ) of 5300 and 2100g/mol, respectively. The ultrathin...
A poly(ethylene oxide) diblock copolymer containing a short block of poly{2,5-bis[(4-methoxyphenyl)oxycarbonyl]styrene} (PEO-b-PMPCS) has been successfully synthesized via atom transfer radical polymerization (ATRP) method. The number average molecular weights (M n ) of the PEO and PMPCS blocks are 5300 and 2100g/mol, respectively. Combining the techniques of differential scanning calorimetry...
Nanocomposite formation of octadecyl amine treated montmorillonite clays in epoxy was investigated by small-angle X-ray scattering and atomic force microscopy. When diglycidyl ether of bisphenol A (DGEBA) was cured with equimolar or higher amounts of meta-phenylene diamine (MPDA), only intercalated nanostructures were obtained. Exfoliated nanocomposites were formed with DGEBA cured with less than...
Characterization of poly(p-oxybenzoate) (POBA) films epitaxially grown on mica and KBr single crystal substrates was performed by atomic force microscopy (AFM). For a thin POBA film sample prepared at 320 o C on a mica substrate, oligomer domains were found in the vicinity of the nuclei, forming an interfacial layer between the mica crystal and the homogeneous POBA film. The AFM study further...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.