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A highly active novel β-nucleating agent for isotactic polypropylene (iPP), cadmium bicyclo[2.2.1]hept-5-ene-2,3-dicarboxylate (BCHE30), was found and its effects on the mechanical properties, the content of β-crystal, and crystallization behavior of iPP were investigated, respectively. The results show that the impact strength and crystallization peak temperature of nucleated iPP are greatly increased,...
The response to mechanical loading of the thermosetting resin system RTM-6 has been investigated experimentally as a function of strain rate and a constitutive model has been applied to describe the observed and quantified material behaviour. In order to determine strain rate effects and to draw conclusions about the hydrostatic stress dependency of the material, specimens were tested in compression...
Tooth extraction induces residual ridge resorption which impairs function and aesthetic of dental prostheses. This study aimed at developing new bone scaffolds to be used in a tooth socket for preserving bone mass from the residual ridge resorption. Scaffolds were fabricated from poly(1,4-butylene succinate) extended with 1,6-diisocyanatohexane (PBSu–DCH) by solvent casting and particulate leaching...
A coarse-grained model previously proposed to perform Monte Carlo simulations for several dendrimer molecules with different topologies and chemical compositions in solution is employed now to obtain structural properties, such as the bead density profile, the asphericity and the molecular scattering factor, or form factor. It is also used to study the Rouse dynamics, including Rouse spring forces...
Different non-conventional polyurethane networks crosslinked with a hyperbranched polyester (Boltorn ® H40) were synthesised with an aim to determine the influence of the polyurethane chemical structure as well as of the length of the linear chains between crosslinking centres on molecular relaxations in such systems. For that purpose, both polyether- and polyester-type macrodiols as well...
Design and control of architecture of polymer are important keys to develop novel polymers. Combination of classic template polymerization and recent controlled/living radical polymerization has enabled the simple and convenient synthesis of well-defined methacrylate type ladder-like polymer and cyclic electrolytic oligomer. In this manuscript, the basic concept and specific features of template polymerization...
Isothermal crystallization of isotactic polypropylene (iPP)/organic montmorillonite (OMMT) binary nanocomposite and iPP/OMMT/poly(ethylene-co-octene) (PEOc) ternary nanocomposites has been investigated by polarized optical microscopy (POM), rheometry and scanning electron microscopy (SEM). At the stage of nucleation the heterogeneous nucleation effect of OMMT was much greater than the concentration...
In this work, both 1D and 2D ATR-FTIR analyses were applied to study the behaviors of the PEO–PPO–PEO tri-block copolymer (Pluronic-F88) aqueous solution during the thermal gelling process. Furthermore, a novelly synthesized phosphorylcholine-modified F88 was also studied by the same technique, for the explanation to its different performance in the rheological study, as compared to F88. It was mainly...
New unsymmetrical diamine monomer containing both the benzimidazole ring and trifluoromethyl group, 6,4′-diamino-2′-trifluoromethyl-2-phenylbenzimidazole, was prepared from 2-bromo-5-nitrobenzotrifluoride and 4-nitro-1,2-phenylenediamine. The monomer was polymerized with ODPA, BTDA and 6FDA by using one-pot synthetic method to obtain corresponding polyimides. All the prepared polyimides were soluble...
A detailed SAXS study of self-assembled block copolymer-based supramolecules composed of a polyisoprene-block-poly(2-vinylpyridine) diblock copolymer and octyl gallate that is hydrogen bonded to the vinylpyridine block in a stoichiometric ratio is presented. The changes in the system morphology with temperature are investigated both at rest and under oscillatory shear. In between the lamellar-to-cylindrical...
The molecular structure and dynamics of a vinylidene fluoride oligomer telomerized by carbon tetrachloride (Cl-OVDF) and its inclusion compound (IC) with β-cyclodextrin (β-CD) have been investigated using solid-state 19 F magic angle spinning (MAS) and 1 H→ 19 F cross-polarization (CP)/MAS NMR spectroscopy. The preferential IC formation of the lower-molecular-weight components...
Manipulation of molecular orientation alignment in MCTLCPs (main-chain thermotropic liquid crystalline polymers) by pure shear at nano scale has been investigated for the first time using molecular dynamics (MD) simulation. Results indicate that high planar shear induces long-range uniform orientation ordering (liquid crystalline phase) of initially randomly orientated molecules of MCTLCP fluid confined...
This paper focuses on developing radiation tolerant polymeric films by incorporating small molecule dopants into the material formulation. The radiation tolerance is imparted to the polymer by dopants capturing the mobile electrons generated upon radiation exposure. A wide range of conjugated small molecules was utilized for the reduction of radiation-induced conductivity (RIC) in semi-crystalline...
Two-dimensional (2D) correlation FTIR spectroscopy was used to investigate the dynamic mechanism of poly(aspartic acid) during the heating process. According to the 2D asynchronous correlation spectra, the CO vibration band of Amide I was separated into three peaks at 1637, 1645 and 1677cm −1 , assigned to α helical, random coil and β antiparallel conformation, respectively. And α helical...
Stereoblock poly(lactic acids) (sb-PLAs), having abundant enantiomeric compositions of poly(l-lactic acid) (PLLA), were successfully synthesized by solid-state polycondensation (SSP) of the melt blends of medium molecular weight prepolymers: both PLLA and poly(d-lactic acid) (PDLA) that had primarily been prepared by melt-polycondensation. The molecular weight of the resultant PLLA-rich sb-PLA was...
Continuous polymer nanofiber yarns were manufactured by self-bundling electrospinning method. Compared with typical electrospinning setup, the special difference in this method was that a grounded needle tip was used to induce the self-bundling of polymer nanofibers at the beginning of electrospinning process. Four kinds of polymer self-bundling yarns, poly(3-hydroxybutyrate-co-3-hydroxyvalerate)...
In this paper, a new method to prepare polymer colloid particles stabilized by triblock copolymer with CdS nanoparticles was described. Poly(ethylene glycol-block-styrene-block-2-(dimethylamino) ethyl methacrylate) (PEG-b-PS-b-PDMAEMA) triblock copolymer was synthesized by sequential ATRP method. Micelles with CdS nanoparticles in the corona were prepared by “in situ” reaction of hydrogen sulfide...
A series of water-soluble cationic polyfluorene copolymer containing 2,2′-bipyridine moieties (PFP-P 1–3 ) in the backbone were designed and synthesized as the fluorescent probes for Cu 2+ ions. In the absence of the Cu 2+ ion, the PFP-P 2 exhibits strong fluorescence emission in aqueous solution. Upon adding the Cu 2+ ion, the PFP-P 2 coordinates to...
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