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Isotactic polystyrene was electrospun into ultrafine fibers from the chloroform or tetrahydrofuran solutions. Tubular or ribbon-like fibers with many small pores were obtained from the chloroform solution. Densely stacked lamellae were formed by annealing them. On the other hand, fibers with many small dents on the skin layer were obtained from the tetrahydrofuran solution. The skin layer changed...
A silicate-selective polymer-supported reagent has been developed that utilizes the reactivity of silicate to generate polyanionic Keggin structures. Heptamolybdate and heptatungstate anions are immobilized onto trimethylammonium ligands bound to microporous poly(vinylbenzyl chloride) beads. The heptamolybdate complexes >90% of the silicate from a 20ppm solution at pH 7; the heptatungstate has...
Using three high sensitive pressure transducers located inside a slit-die of a capillary rheometer and applying a set of advanced mathematical tools to process the acquired time dependent pressure signals, we are able to detect in-situ pressure fluctuations associated with sharkskin instabilities. Other distortions, as spurt and gross melt fracture, can also be in-situ detected. This originates from...
High molecular weight sulfonated poly(arylenethioethersulfone) homopolymer containing hexafluoroisopropylidene moiety (6F-SPTES-100) was synthesized from the monomers 3, 3′-disulfonated-4, 4′-difluorodiphenylsulfone and 4, 4′-(hexafluoroisopropylidene) diphenylthiol, using 4-fluorobenzophenone as the end-capping agent in polar aprotic solvents at temperatures up to 180 °C to provide the desired polymeric...
The structural stability of impact polypropylene copolymer (IPC) melt under high temperatures was explored by dynamic rheological measurement. The structure changes including degradation and crosslinking of IPC were discussed through examining the influence of temperature and additive antioxidant on dynamic rheological functions. A plateau of dynamic storage modulus (G′) appeared in low frequency...
The glass transition temperature (T g ) of nanoporous polyetherimide (PEI) and PEI thin films was investigated. The T g decreased from its bulk value in both of these confined systems. Monte Carlo simulations were performed to calculate the nearest neighbor pore-to-pore distances in the nanoporous PEI. A quantitative analogy between the nanoporous PEI and PEI thin films is proposed...
Monophenylated poly(ether sulfone)s (Ph-PES) and diphenylated poly(ether sulfone)s (DiPh-PES), were synthesized as starting materials for the preparation of sulfonated polymers with well-defined chemical structure. Mild post-polymerization sulfonation conditions led to sulfonated Ph-PES (Ph-SPES) bearing acid groups on both the pendant phenyl group and the backbone, and sulfonated DiPh-PES (DiPh-SPES)...
Phenanthrene α-end-labeled poly(N-decylacrylamide-b-N,N-diethylacrylamide) (PDcA n -b-PDEA m ) block copolymers consisting in a highly hydrophobic block (n=11) and a thermoresponsive block with variable length (79≤m≤468) were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization. A new phenanthrene-labeled chain transfer agent (CTA) was synthesized and...
Radical copolymerization behavior of methyl 2-norbornene-2-carboxylate 1 and 2-phenyl-2-norbornene 2 was investigated. Radical copolymerization of 1 and 2 with styrene, alkyl acrylate, and methyl methacrylate in a variety of monomer combinations afforded copolymers, whose main chains consisted of norbornane framework. Relative monomer reactivity ratios for the copolymerization of 1 and 2 with n-butyl...
This manuscript describes the preparation of polytriazole/clay nanocomposites through in situ polymerization of PTA, using click chemistry, in the presence of a propargyl-modified clay. The clay layers became exfoliated and dispersed well in the PTA matrix, thereby improving the thermal and mechanical properties of the clay. This approach can be extended to combine propargyl-modified clays with other...
Cellulose is a future major source of materials and biofuel but its extraction and its chemical or enzymatic treatments are difficult, polluting and inefficient tasks. The accessibility of the reagents to cellulose chains is indeed limited. Classical evocated reasons for this lack of accessibility are pore structure, tight hydrogen bond arrays, crystallinity and presence of resistant materials like...
The properties of amphiphilic polyether macromonomers and their behaviour during homo-polymerisation in water and in water/benzene mixture are reported. Homo-poly(glycidol) macromonomer bearing polymerisable p-vinyl benzyl end groups (PGl55-St) and two block poly(glycidol)-b-poly(glycidyl phenyl ether) macromonomers, containing polymerisable p-vinyl benzyl end groups attached to the hydrophobic (PGl52-b-PGlPhE8-St)...
We have developed two approaches to processable precursors to conjugated polymers: main-chain and side-chain. Upon oxidative conversion to the conjugated polymer, a main-chain precursor yielded a nearly perfect spectral match, an identical λ max , and an equivalent band gap to that of electrodeposited chromophore, resulting in a color match. This precursor method has the potential to incorporate...
This paper presents correlations between polyethylenes of different compositions and branching architectures and their viscoelastic behavior in dependence on the temperature and demonstrates how effectively rheological experiments can be used for analytical purposes. Long-chain branched polyethylenes are known to be thermorheologically complex. But the thermorheological complexity of long-chain branched...
A series of conjugated polymer bearing 4H-cyclopenta[def]phenanthrene (CPP) unit have been synthesized and was evaluated in bulk heterojunction solar cell. The alternating copolymers with CPP unit were incorporated with 4,7-dithienyl-2,1,3-benzothiadiazole (DTBT) unit by Suzuki conditions. The newly synthesized copolymers, poly(2,6-((4,4-bis(2-ethylhexyl)-4H-cyclopenta[def]phenanthrene))-alt-(4,7-((2-thienyl)-2,1,3-benzothiadiazole)))...
Molecularly imprinted polymers are synthetic materials designed to selectively bind to a templated molecule. In this study, the effect of including both positive and negative charges simultaneously into the hydrogel network on the selective recognition properties of the MIP is examined. Using 3-methacrylamidopropyl trimethylammonium chloride (MAPTAC) as a cationic monomer and 2-acrylamido-2-methylpropane...
A novel injectable in situ cross-linked hydrogel has been designed via Michael type addition between thiol-modified chitosan (CS–NAC) and PEG diacrylate (PEGDA). Hydrogel was rapidly formed in situ under physiological conditions. The gelation time depended on the content of free thiols in CS–NAC, temperature, and concentration of CS–NAC and PEGDA. Thermogravimetric analysis showed the thermal stabilities...
The block copolymers consisting of 2,7-dimethoxycarbazole- and oxadiazole-containing segments as hole and electron transporting units, respectively, were synthesized by NMRP manner. OLED devices were fabricated using block copolymer, random copolymer, and polymer blend for matrix of the emitting layer with Ir(ppy) 3 as a phosphorescent dopant in order to investigate morphological effect on...
The novel separation method, liquid chromatography under limiting conditions of desorption, LC LCD enables rapid one-step discrimination of both parent homopolymers from diblock copolymers. The low-molecular admixtures/impurities can be base-line separated, as well. The general rules for selection of the LC LCD columns are reviewed. Bare silica gel column packings are discussed in detail. Selected...
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