33527-91-2Relevant articles and documents
Luminescent Nanocellulose Platform: From Controlled Graft Block Copolymerization to Biomarker Sensing
Navarro, Julien R. G.,Wennmalm, Stefan,Godfrey, Jamie,Breitholtz, Magnus,Edlund, Ulrica
, p. 1101 - 1109 (2016)
A strategy is devised for the conversion of cellulose nanofibrils (CNF) into fluorescently labeled probes involving the synthesis of CNF-based macroinitiators that initiate radical polymerization of methyl acrylate and acrylic acid N-hydroxysuccinimide ester producing a graft block copolymer modified CNF. Finally, a luminescent probe (Lucifer yellow derivative) was labeled onto the modified CNF through an amidation reaction. The surface modification steps were verified with solid-state 13C nuclear magnetic resonance (NMR) and Fourier transform infrared spectroscopy. Fluorescence correlation spectroscopy (FCS) confirmed the successful labeling of the CNF; the CNF have a hydrodynamic radius of about 700 nm with an average number of dye molecules per fibril of at least 6600. The modified CNF was also imaged with confocal laser scanning microscopy. Luminescent CNF proved to be viable biomarkers and allow for fluorescence-based optical detection of CNF uptake and distribution in organisms such as crustaceans. The luminescent CNF were exposed to live juvenile daphnids and microscopy analysis revealed the presence of the luminescent CNF all over D. magna's alimentary canal tissues without any toxicity effect leading to the death of the specimen. (Graph Presented).
Ciampolini,Nardi
, p. 41,42-44 (1966)
Synthesis of SET-LRP-induced galactoglucomannan-diblock copolymers
Dax, Daniel,Xu, Chunlin,Langvik, Otto,Hemming, Jarl,Backman, Peter,Willfoer, Stefan
, p. 5100 - 5110 (2013)
Polysaccharides are biorenewable and biodegradable starting materials for the development of functional materials. The synthesis of a monofunctional macroinitiator for single electron transfer-living radical polymerization was successfully developed from a wood polysaccharide-O-acetyl galactoglucomannan (GGM) using a beforehand synthesized amino-functional α-bromoisobutyryl derivative applying reductive amination. The GGM macroinitiator was employed to initiate a controlled radical polymerization of [2-(methacryloyloxy)ethyl] trimethylammonium chloride (MeDMA), methyl methacrylate (MMA), and N-isopropylacrylamide (NIPAM) using Cu0/Me6-Tren as a catalyst. The either charged or amphiphilic GGM-b-copolymers with different chain lengths of the synthetic block were successfully synthesized without prior hydrophobization of the GGM chain and dimethyl sulfoxide (DMSO) or DMSO/water mixtures were used as solvents. This novel synthetic approach may find untapped potentials particularly for the development of polysaccharide-based amphiphilic additives for cosmetics or paints and for the design of novel temperature or pH responsive polymers with such potential applications as in drug delivery systems or in biocomposites. Copyright
Star-shaped trimeric quaternary ammonium bromide surfactants: Adsorption and aggregation properties
Yoshimura, Tomokazu,Kusano, Takumi,Iwase, Hiroki,Shibayama, Mitsuhiro,Ogawa, Tetsuya,Kurata, Hiroki
, p. 9322 - 9331 (2012)
Novel star-shaped trimeric surfactants consisting of three quaternary ammonium surfactants linked to a tris(2-aminoethyl)amine core were synthesized. Each ammonium had two methyls and a straight alkyl chain of 8, 10, 12, or 14 carbons. The adsorption and aggregation properties of these tris(N-alkyl-N,N- dimethyl-2-ammoniumethyl)amine bromides (3CntrisQ, in which n represents alkyl chain carbon number) were characterized by equilibrium and dynamic surface tension, rheology, small-angle neutron scattering (SANS), and cryogenic transmission electron microscopy (cryo-TEM) techniques. 3C ntrisQ showed critical micelle concentrations (CMC) 1 order of magnitude lower than that of the corresponding gemini surfactants with an ethylene spacer and the corresponding monomeric surfactants. The logarithm of the CMC decreased linearly with increasing hydrocarbon chain length for 3C ntrisQ. The slope of the line, which is well-known as Klevens equation, was larger than those of the monomeric and gemini surfactants; however, considering the total carbon number in the chains, the slope was shallower than the monomeric and was close to the gemini. Through the results such as surface tensions at the CMC (32-34 mN m-1) and the parameters of standard free energy, CMC/C20 and pC20, it was found that 3CntrisQ could adsorb densely at the air/water interface despite the strong electrostatic repulsion between multiple quaternary ammonium headgroups. Moreover, dynamic surface tension measurements showed that the kinetics of adsorption for 3CntrisQ to the air/water interface was slow because of their bulky structures. Furthermore, the results of rheology, SANS, and cryo-TEM determined that 3CntrisQ with n = 10 and 12 formed ellipsoidal micelles at low concentrations in solution and the structures transformed to threadlike micelles with very few branches for n = 12 as the concentration increased, but for n = 14 threadlike micelles formed at relatively low concentrations.
Physicochemical and solution properties of quaternary-ammonium-salt-type amphiphilic trimeric ionic liquids
Kawai, Risa,Yada, Shiho,Yoshimura, Tomokazu
, p. 25065 - 25071 (2019)
The quaternary-ammonium-salt-type amphiphilic compounds 3Cntris-s-Q X (star-type; carbon number between the central amino and ammonium groups s = 2, 3) and 3Cnlin-3-Q X (linear-type; carbon number between the hydrophilic groups s = 3), where n represents the alkyl chain length (n = 8, 10, 12, 14) and X represents a counterion [hexafluorophosphate, trifluoromethanesulfonate (OTf), bis(fluorosulfonyl)amide (FSA), and bis(trifluoromethanesulfonyl)amide (NTf2)], were synthesized. Except for 3C12tris-3-Q OTf, these trimeric compounds presented melting points lower than 100 °C and therefore are defined as ionic liquids. Among them, 3Cntris-3-Q NTf2 (n = 8, 12, 14) and 3Cnlin-3-Q NTf2 (n = 8, 10) presented melting points lower than 0 °C. The melting points of the amphiphilic trimeric ionic liquids (n = 8, 10), which were lower for the star- than for the linear-type compounds, were higher than those of the corresponding monomeric compounds but lower than those of the corresponding gemini samples. Moreover, the amphiphilic trimeric ionic liquids exhibited higher conductivities and lower viscosities than the corresponding gemini ionic liquids, while the star-type trimeric ionic liquids presented lower conductivities and higher viscosities than those of the linear-type compounds. The amphiphilic trimeric ionic liquids also readily adsorbed at the air/water interface and oriented themselves to form micelles in aqueous solution. This aggregation behavior was not observed in the monomeric and gemini ionic liquids.
Synthesis of inimers and hyperbranched polymers
-
Page/Page column 21, (2013/09/12)
An inimer, and process for making same, having the following formula: wherein X=halogen, nitroxide, thioester; R═H or CH3; and R′=aliphatic, non-aliphatic, linear or branched, mesogenic, non mesogenic, chiral, achiral, hydrocarbon, non-hydrocarbon, selected from fluorocarbon, oligo(oxyethylene) and siloxane substituents, alkyl, aryl, mesogenic group, non-mesogenic group, aliphatic, non-aliphatic, siloxane, perfluoroalkyl, perfluoroaryl, or other fluorocarbon group, and polymers, and the process of making them, from the inimer.
