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Layered double hydroxide (LDH) organo-modified by a surface-active monomer, 3-sulfopropyl methacrylate (SPMA) was used as filler for polystyrene (PS). Different nanocomposites SPMA/LDH:PS were prepared by bulk polymerization process using low amount of initiator. The two components, filler and polymer, as well as the degree dispersion of the reactive filler as a function of its loading in PS were...
A novel diamine monomer, 2,4-diamino-4′-carboxy diphenyl ether had been synthesized. Several polyimides were prepared by reacting this diamine with commercially available dianhydrides, such as benzophenone tetracarboxylic acid dianhydride (BTDA), 4,4′-bis{hexafluoroisopropylidene bis (phthalic anhydride)}(6-FDA), oxydiphthalic anhydride (ODPA) and 3,3′,4,4′-biphenyltetracarboxylic acid dianhydride...
In order to combine the properties of polymers based on vinylidene chloride (VC 2 ) (barrier properties towards many gases) and fluorinated polymers (low surface energy, improvement of the chemical resistance), a diblock terpolymer poly(VC 2 -co-MA)-b-(PFDA) was synthesized by RAFT process. The first block is a statistical copolymer of vinylidene chloride (VC 2 ) and methyl...
The homopolymerization of 5-alkyl-2-norbornenes and their copolymerization with norbornene have been successfully carried out employing Pd(acac) 2 /PPh 3 /BF 3 OEt 2 catalyst system. The activity of the catalyst system is comparable to that of most active late-transition metal catalysts described in the literature. The molecular weight distributions of homo- and copolymers...
A novel hyaluronan (HA) derivative was synthesized through silylation reaction to improve the hydrophobicity of HA, to enhance its solubility in common organic solvents, and to make it more reactive for further derivatizations (e.g. esterification). While HA can not be silylated directly, its ion-paired complex with a long aliphatic chain quaternary ammonium salt (HA–CTA) was an effective starting...
Two poly(p-phenylenevinylene) derivatives, TPA-PPV and TPA-CN-PPV, bearing a triarylamine pendant were synthesized by the Wittig-Horner and Knoevenagel reactions, respectively. The optical properties of the polymers were improved by energy transfer from the triarylamine pendant to the poly(p-phenylenevinylene) main chain. Cyclic voltammetry revealed that the HOMO energy level of the pendant TPA moiety...
We have generated porous polybenzoxazine (PBZZ) materials by using a B-a type PBZZ as the matrix and various molecular weights of poly(ε-caprolactone) (pa-PCL) as the labile constituent. The slight degree of hydrogen bonding that exists between the two polymers results in micro-phase separation without an excess degree of aggregation occurring. The porous structures form after hydrolysis of the PCL...
We study the mechanical and conformational properties of networks of helical polymers with a combination of Monte Carlo simulations based on the Wang–Landau algorithm and the three-chain model. We find that the stress–strain behavior of these networks has novel features not observed in typical networks made of synthetic polymers. In particular, we find that as these networks are stretched they first...
A systematic investigation was made of the effects of varying hard and soft segment chemistry, crosslinking and preparation procedures, on the mechanical response of melt-cast polyurethane elastomers. In particular, two hard segments were compared, based on the diisocyanates: 4,4′-methylene bis(phenyl isocyanate) (MDI) and 4,4′-dibenzyl diisocyanate (DBDI). Rotation around the central –CH 2 ...
Owing to the increasing interest in self-assembled structures from block copolymer materials, we present here a review of recent literature concerning amphiphilic block copolymer vesicles. A vesicular morphology is applicable not only in such fields like delivery–release and biomineralization, but also has been utilized for preparation of nanoreactors and incorporation of biological macromolecules...
Novel PANI nanorods with average diameter of 21–53nm and length of 0.5–1μm were synthesized by dispersion polymerization method. The morphology of obtained PANI nanorods was significantly dependent on the type of salt, stirring, and polymerization temperature. Dispersion polymerization with FeCl 3 produced longer nanorods than ammonium persulfate (APS) and magnetic stirring decreased the length...
Different synthetic pathways leading to polythiophenes (PTs) containing units derived from methyl N-(tert-butoxycarbonyl)-S-3-thienyl-l-cysteinate (1) and methyl N-(tert-butoxycarbonyl)-S-(2-thien-3-ylethyl)-l-cysteinate (2) were investigated. The oxidative coupling with FeCl 3 applied to N-deprotected monomer 1 generates a chemically fleeting PT, whereas when applied to N-deprotected monomer...
The monomeric Nd-catalyst composed of Nd(neodecanoate) 3 ·(neodecanoic acid)(NdV4)/AlEt 2 Cl/Al(iBu) 3 showed a high activity (2.0×10 6 g/Ndmolh), and the monomeric active-center was proposed through density functional calculations (B3LYP/CEP-31G). The microstructure of polybutadiene was controlled by chain–transfer with NdV4, catalyst composition and phosphine compounds...
Polymer electrolytes with high ionic conductivity and good elasticity were prepared by mixing nitrile rubber (poly(acrylonitrile-co-butadiene) rubber; NBR) with ionic liquid, N-ethylimidazolium bis(trifluoromethanesulfonyl)imide (EImTFSI). The NBR/EImTFSI composites were obtained as homogeneous and transparent films when the ionic liquid content was less than 60wt%. Raman spectroscopy suggested the...
A regular and well-interconnected macroporous (from 50 to 200μm) poly(d,l-lactic acid-co-glycolic acid) (PLGA) scaffold was fabricated by means of the thermally induced phase separation (TIPS) method. Poly(l-lactic acid) (PLLA) was blended with PLGA to increase the viscosity of polymer solution; a block copolymer of poly(ethylene glycol) (PEG) with PLGA was added as a surfactant to decrease the interfacial...
Solution and melt blends have been prepared by mixing polyamide 6 (PA6) with hyperbranched (HB) aromatic polyamides (aramids) synthesized from A 2 (p-phenylenediamine)+B 3 (trimesic acid) reactants. The HB aramids (pPDT), were obtained using various polymerization conditions, hence were characterized by different content and ratio of –COOH and –NH 2 end group functionalities,...
A porous material consisting of biodegradable polymer fibers may be one of the best candidates for implants used in the regeneration of damaged tissue, because it has a continuous pore structure that would allow ingrowth of nutriments, tissues, blood vessels or cells. In the present work, short fibers of biodegradable poly(l-lactic acid) (PLLA) were successfully prepared by the dropwise addition of...
Ring-opening polymerization (ROP) of l-lactide was combined with atom transfer radical polymerization (ATRP) to produce well-defined linear block copolymers. Poly(l-lactide) (PLLA) was synthesized via ROP using ethylene glycol as an initiator and stannous octoate as a catalyst. The isolated hydroxy-telechelic PLLA was reacted with thionyl chloride and pyridine in toluene to afford chloro-telechelic...
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