Block Copolymers
Mostrando 1-12 de 51 artigos, teses e dissertações.
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1. Synthesis and characterization of mesoporous materials with SBA and MCM structure types
Resumo Materiais mesoporosos são estruturas promissoras para aplicação em catálise e adsorção devido à elevada área superficial e grande tamanho dos poros. Materiais mesoporosos foram sintetizados pelo método hidrotérmico com novos surfactantes, distintos daqueles observados na literatura, a fim de realizar um estudo de sua estrutura e obter materi
Cerâmica. Publicado em: 14/11/2019
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2. Numerical Simulation of Atom-Transfer Radical Polymerization of tert-butyl Methacrylate
Block copolymers based on tert-butyl methacrylate (tBMA) have many uses, such as thermo‐responsive polymers, amphiphilic copolymers, and many applications in the medical field. Atom-transfer radical polymerization (ATRP) is the main technique to produce these controlled macromolecular architectures. This paper provides a simplified kinetic modeling and com
Mat. Res.. Publicado em: 02/09/2019
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3. Synthesis and characterization of amphiphilic block copolymers by transesterification for nanoparticle production
Abstract Poly(ε-caprolactone)-block-poly(ethylene glycol)-poly(ε-caprolactone) (PCL-PEG-PCL, triblock) and Poly(ε-caprolactone)-block-(poly(ethylene oxide)−poly(propylene oxide)−poly(ethylene oxide)-poly (ε-caprolactone) (PCL-PEO-PPO-PEO-PCL, pentablock) copolymers were synthesized by transesterification with reduction of PCL molecular mass, enabling
Polímeros. Publicado em: 04/07/2019
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4. Thermal degradation of polymer systems having liquid crystalline oligoester segment
Abstract Block copolymers and blends comprised by liquid crystalline oligoester and polystyrene were prepared and their thermal stability were characterized by thermogravimetric analysis (TGA). The samples have shown three main decomposition temperatures due to (1) lost of flexible chain and decomposition of mesogenic segment, (2) decomposition of polystyren
Polímeros. Publicado em: 2017-12
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5. POLIMEROSSOMOS VERSUS LIPOSSOMOS: A EVOLUÇÃO DA “BALA MÁGICA”
Polymeric vesicles known as polymersomes are formed by the self-assemble of amphiphilic block copolymers and have structural organization similar to liposomes. However, polymersomes present higher physicochemical stability and structure versatility due to their polymeric nature. In this review we describe the main aspects related to the structure and applica
Quím. Nova. Publicado em: 2017-08
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6. Synergistic Effect in Drug Solubility by New Binary Micelles of Poly(ε-caprolactone)-poly(ethylene oxide) and F127®
Binary mixtures of block copolymers E114CL20 and E97P69E97 (F127(®)) were prepared in order to tailor a drug delivery system with synergistic effect, concerning dilution stability and high drug solubility. Both reduction of the critical micelle concentrations (CMC) values and enhance hydrophobic drug solubility in F127/E114CL20 mixtures (30-50 wt.%) were ob
J. Braz. Chem. Soc.. Publicado em: 2017-07
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7. Preparation of Polymeric Micelles of Poly(Ethylene Oxide-b-Lactic Acid) and their Encapsulation With Lavender Oil
Nanoparticles comprised of the poly(ethylene oxide)-b-poly (lactic acid) diblock copolymer (PEO-b-PLA) with and without the incorporation of lavender oil were prepared by nanoprecipitation. Diblock copolymers based on a fixed PEO block (5KDa) and two different PLA segments (4.5 or 10KDa) were used. The morphology, encapsulation efficiency, essential oil-poly
Mat. Res.. Publicado em: 03/10/2016
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8. Synthesis and applications of polystyrene-block-poly(N-vinyl-2-pyrrolidone) copolymers
Abstract This work describes the synthesis and applications of amphiphilic polystyrene-block-poly(N-vinyl-2-pyrrolidone) (PS-b-PVP) copolymers as a silver and silica nanoparticle surface modification agent. The synthesis of PS-b-PVP was carried out using controlled/living radical polymerization techniques. The synthesis of the block copolymers was confirmed
Polímeros. Publicado em: 15/03/2016
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9. Synthesis and Characterization of Polydimethylsiloxane end-Modified Polystyrene from Poly(Styrene – co –Vinyltriethoxysilane) Copolymers
In this paper, we report the synthesis of polystyrene end- capped with three- short- arm PDMS (PS-(PDMS)3) using poly(styrene – co–vinyltriethoxysilane) copolymers as precursors. These materials were obtained in a two-step process; first, two random copolymers of poly(St –co – VTES) having different molecular weight, and vinyltriethoxysilane content
Mat. Res.. Publicado em: 11/03/2016
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10. Urea decreases specific ion effects on the LCST of PMMA-block-PDMAEMA aggregates
Urea is a well-known additive used as a mild protein denaturant. The effect of urea on proteins, micellar systems and other colloids is still under debate. In particular, urea has shown interesting effects on the ion binding in systems like charged micelles, vesicles or Langmuir-Blodgett films. The urea effect on polymeric aggregates in water is still an ope
Polímeros. Publicado em: 2014-12
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11. Synthesis of stimuli-sensitive copolymers by RAFT polymerization: potential candidates as drug delivery systems
Poly(2-(dimethylamino)ethylmethacrylate-b-methymethacrylate) (PDMAEMA-b-PMMA) poly(2-(dimethylamino)ethylmethacrylate-b-vinylcaprolactam-b-(2-(dimethylamino)ethyl methacrylate) (PDMAEMA-b-PVCL-b-PDMAEMA) and poly(vinylcaprolactam-b-(2-(dimethylamino)ethylmethacrylate-b-vinylcaprolactam) (PVCL-b-PDMAEMA-b-PVCL) block copolymers were obtained by reversible add
Mat. Res.. Publicado em: 25/03/2014
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12. Physico-chemical properties of meso-tetrakis(p-methoxyphenyl)porphyrin (TMPP) incorporated into pluronicTM p-123 and f-127 polymeric micelles
The physicochemical properties (solubilization, structural organization and stability) of meso-tetrakis(p-methoxyphenyl)porphyrin (TMPP), a promising photosensitizer for photodynamic therapy, solubilized in polymeric micelles of tri-block copolymers PluronicTM P-123 and F-127, were studied. The formulations obtained by the solid dispersion method led to mono
Quím. Nova. Publicado em: 2014