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A series of novel amphiphilic, conjugated triblock copolymers of poly(9,9-didodecylfluorene-2,7-diyl) (PF) were synthesized. The rod-like PF midblock was synthesized via a Yamamoto-type reaction of 2,7-dibromo-9,9-di-n-dodecylfluorene, and endcapped with 4-bromobenzyl alcohol to obtain the hydroxyl end-functionalized PF (PFOH). A series of α-monocarboxy-ω-mono-methoxy poly(ethylene glycol)s with various...
A central challenge in the development of polymeric nanoparticles for various applications is precise engineering of desired physicochemical characteristics in a reproducible manner. The present work concerns the use of microfluidics to control the local polymer concentration inside polymeric nanoparticles. It is demonstrated that the compactness of nanoparticles based on self-assembled hydrophobically...
The self-assembly and phase transition diagrams of cellulose nanowhiskers derived from tunicates, food grade bacterial cellulose (nata-de-coco) and lab cultured bacterial cellulose are reported. The phase transition diagram for isotropic to liquid crystalline phase transition has been developed for cellulose nanowhiskers obtained from all these sources by recording phase separation behaviour and polarised...
Structurally well-defined C 4 F 9 , C 7 F 15 , C 10 F 21 and C 13 F 27 end-functionalized polystyrene (RF-PS) and polybutylmethacrylate (RF-PBMA) were prepared by Atom Transfer Radical Polymerization using RF–tagged initiators. Blends (1/1 wt/wt) of these polymers were studied by differential scanning calorimetry (DSC), atomic force microscopy...
Effects of polarons on the single (NH4OH) and double (NH4OH + LiOH) dedoped nanostructured products obtained in the oxidative polymerization of aniline are investigated. These effects are probed by 15N and 13C solid-state NMR, FTIR, Raman and EPR spectroscopy. The morphologies were imaged using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The micrographs confirmed...
The phase behavior of coil-comb copolymers A–(B m+1 C m ) (side chain number m = 1–5) is investigated by real-space self-consistent field theory (SCFT). Depending on the copolymer composition and architecture, eight two-dimensional ordered phases are observed, including two-color lamellae (LAM 2 ), three-color lamellae (LAM 3 ), hexagonal cylinders (HEX), core–shell...
A series of P(MMA-co-GMA)-b-PMAPOSS block copolymers (BCPs) were synthesized by ATRP. The BCPs contain POSS (polyhedral oligomeric silsesquioxane) as a pendant unit on a particular polymer block chain. In selective solvents, the BCPs self-assemble to form ordered micellar-like structures. Spherical, cylindrical or vesicle-like morphologies were produced by tuning the BCP and mixed solvent compositions...
Using a combination of block copolymer self-assembly and non-solvent induced phase separation, isoporous ultrafiltration membranes were fabricated from four poly(isoprene-b-styrene-b-4-vinylpyridine) triblock terpolymers with similar block volume fractions but varying in total molar mass from 43 kg/mol to 115 kg/mol to systematically study the effect of polymer size on membrane structure. Small-angle...
Sequential thiol-ene click reaction is reported for amphiphilic glycosylated polyphosphazene. Poly[bis(allylamino)phosphazene] was used as precursor to go through UV irradiation with 2,3,4,6-tetra-O-acetyl-1-thiol-β-D-glucopyranose (SH-GlcAc 4 ) and 1-dodecanethiol in sequence. Variation of the reaction conditions, including click reaction time and the dose of photoinitiator, led to different...
Pyrene labelled chain transfer agent, py-CTA, was synthesized and employed for the reversible addition-fragmentation chain transfer (RAFT) polymerization of Boc-phenylalanine/alanine methacryloyloxyethyl ester (Boc-F/A-EMA) based monomers, for obtaining α-pyrene labelled homopolymers, pyrene-poly(Boc-phenylalanine/alanine methacryloyloxyethyl ester) (py-P(Boc-F/A-EMA)), with controlled molecular weight,...
Poly(3-hexylthiophene-2,5-diyl) is among the most widely used conjugated polymers for opto-electronic applications. To enhance its properties, researchers have attempted to nanostructure this polymer using various processes including breath figure arrays, nanolithography and elaborated organic synthesis. We here demonstrate a simple process to nanostructure the conjugated polymer using self-assembly...
Isoporous asymmetric polystyrene-block-poly(4-vinylpyridine) (PS-b-P4VP) hollow fiber membranes were successfully made by a dry-jet wet spinning process. Well-defined nanometer-scale pores around 20–40 nm in diameter were tailored on the top surface of the fiber above a non-ordered macroporous layer by combining block copolymer self-assembly and non-solvent induced phase separation (SNIPS). Uniformity...
The effect of salt on the dissociation behavior of a Pluronic-polyacrylic acid penta-block copolymer (P85PAA65) was examined. The average Gibbs energy corresponding to the energy for extracting a proton from P85PAA65 copolymer chains decreased with increasing NaCl concentration, suggesting that the addition of salt favors the dissociation process. A fluorescence study showed a two-step dissociation...
This paper describes the synthesis, characterization, and self-assembly behavior of amphiphilic polyethylene-block-poly(l-glutamate) (PE-b-PGA) diblock copolymers. PE-b-PGA diblock copolymers were obtained by ring-opening polymerization (ROP) of γ-benzyl-l-glutamate-N-carboxyanhydride (BLG-NCA) using PE–COOCH( i Pr)NH 2 as a macroinitiator and subsequent deprotection of the benzylester...
It has been well documented that self-assembly of block copolymers (BCP) in selective solvents, where the core-forming block is a crystallizable polymer, results in micelle structures with exceptional aggregation morphologies determined mainly by the crystallization energy from the core. In this contribution, we apply this concept to create ribbon-like nanostructures dispersed in an epoxy network...
The impacts of both shear temperature and shear rate on both the self-assembled β-nucleating agent (β-NA) in the hosting isotactic polypropylene (iPP) matrix and the subsequent crystallization of the hosting iPP matrix were investigated by polarized optical microscopy (POM) and wide-angle X-ray diffraction (WAXD), and small-angle X-ray scattering (SAXS) measurements, respectively. Under static condition,...
A series of narrowly distributed diblock copolymers composed of amorphous components and side-chain liquid crystalline (LC) polymer, poly (butyl acrylate)-block-poly [8-(4-cyano-4′-biphenyl)-1-octanoyl acrylate] (PBA-b-PCBOA), with side-chain LC block weight fraction (fw,PCBOA) ranging from 25% to 87%, were synthesized by atom transfer radical polymerization (ATRP). Their thermal property, LC behavior,...
Novel aliphatic polyurethane (PU) nanohybrids have been prepared using varying amount of graphene by dispersing it in the early stage of polymerization (in situ) and achieved uniform distribution throughout the matrix, required for the improvement of properties. The alteration of self-assembly in presence of graphene have been explored through X-ray diffraction, small angle neutron scattering, atomic...
A class of tunable, mesostructured self-assembled hydrogels has been developed based on a library of π–π stacking ABA-type telechelic triblock copolymers prepared by organocatalytic ring-opening polymerization (ROP). Poly(ethylene glycol) (PEG) served as a macroinitiator for ROP of methylene tricarbonate-benzyl ester (MTC-OBn), a benzyl-ester functionalized cyclic carbonate monomer, resulting in polymers...
In order to realize a more effective and environmentally friendly flame-retardant treatment for melamine foam, which is expected to be used as highly flame-retardant cellular polymeric materials for building and construction, a novel intumescent flame-retardant nanocoating, comprised of positively charged chitosan (CH) and negatively charged ammonium polyphosphate (APP), is deposited on high open-cell...
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