Abdurrokhman, Iqbaal; Elamin, Khalid; Danyliv, Olesia; Hasani, Mohammad; Swenson, Jan; Martinelli, Anna
Protic Ionic Liquids Based on the Alkyl-Imidazolium Cation: Effect of the Alkyl Chain Length on Structure and Dynamics
Protic ionic liquids are known to form extended hydrogen-bonded networks that can lead to properties different from those encountered in the aprotic analogous liquids, in particular with respect to the structure and transport behavior. In this context, the present paper focuses on a wide series of 1-alkyl-imidazolium bis(trifluoromethylsulfonyl)imide ionic liquids,…
Effect of processing conditions on the mechanical properties of bio-inspired mechanical gradient nanocomposites
Zhang, Yefei; Edelbrock, Alexandra N.; Rowan, Stuart J.
Photo-induced thiol-ene crosslinking of allyl-functionalized cellulose nanocrystal (CNC)/polymer nanocomposites allows access to films that mimic the water-enhanced mechanical gradient characteristics of the squid beak. These films are prepared by mixing the functionalized CNCs and polymer in a solvent before solution casting and drying. The photocrosslinking agents are then imbibed into…
Nano-modified HDPE/PA6 microfibrillar composites: Effect of aminated graphite platelets coupling
Kelnar, Ivan; Bal, Ümitcan; Zhigunov, Alexander; Kaprálková, Ludmila; Fortelný, Ivan; Krej?íková, Sabina; Kredatusová, Jana; Dybal, Ji?í; Janata, Miroslav; Nofar, Mohammadreza
Modification of microfibrillar composites (MFCs) by nanofillers shows important effects of its localization on performance. This work deals with control of migration/localization of amine-modified graphite nanoplatelets (GNPAs) in the HDPE/PA6 system through their in situ coupling. GNPA/HDPE linking also leads to complex morphology of PA6 fibers. Although such control of…
Gas separation properties of polybenzimidazole/thermally-rearranged polymer blends
Moon, Joshua D.; Bridge, Alexander T.; D’Ambra, Colton; Freeman, Benny D.; Paul, Donald R.
Polybenzimidazole (PBI) is highly selective for H2 removal from mixtures with CO2, but it exhibits low gas permeabilities. Celazole® PBI was blended with more permeable HAB-6FDA-CI, an ortho-functional thermally rearrangeable polyimide, to improve its gas permeabilities while attempting to maintain high selectivity. A compatibilizer, 1-methylimidazole, enhanced phase dispersion when added…
Aggregation behavior of the amyloid model peptide NACore
Pallbo, Jon; Sparr, Emma; Olsson, Ulf
The aggregation of the 11 residue long NACore peptide segment of ?-synuclein (68-GAVVTGVTAVA-78) has been investigated using a combination of cryogenic transmission electron microscopy (cryo-TEM), small- and wide-angle X-ray scattering, and spectroscopy techniques. The aqueous peptide solubility is pH dependent, and aggregation was triggered by a pH quench from pH…
Preparation of cellulose nanofibers from Miscanthus x. Giganteus by ammonium persulfate oxidation
Yang, Han; Zhang, Yefei; Kato, Ryo; Rowan, Stuart J.
Carboxylic acid functionalized cellulose nanofibers (MxG-CNFA-CO2H) were successfully isolated from a sustainable grass hybrid Miscanthus x. Giganteus by a new two-step chemical oxidation, that involves bleach treatment and ammonium persulfate oxidation, followed by ultrasonication. The resulting MxG-CNFA-CO2Hs have ca. 1200?mmol/kg carboxylic acid surface groups, an aspect ratio of 230 (height
Investigation of Micromechanical Behavior and Voiding of Polyethylene Terephthalate/Polyethylene-stat-methyl Acrylate Blends during Tensile Deformation
Lee, Bongjoon; Onbulak, Sebla; Xu, Yuewen; Topolkaraev, Vasily; McEneany, Ryan; Bates, Frank; Hillmyer, Marc
Micromechanical deformation of polyethylene terephthalate (PET)/ethylene-stat-methyl acrylate copolymer blends was investigated for various MA contents and molar masses of p(E-s-MA). The copolymers were synthesized by ring-opening metathesis polymerization and subsequent hydrogenation. Varying the MA content and molar mass of the copolymer alters the interfacial adhesion between the
Transparent, Lightweight, and High Strength Polyethylene Films by a Scalable Continuous Extrusion and Solid-State Drawing Process
Lin, Yunyin; Tu, Wei; Verpaalen, Rob C. P.; Zhang, Han; Bastiaansen, Cees W. M.; Peijs, Ton
The continuous production of transparent high strength ultra-drawn high-density polyethylene films or tapes is explored using a cast film extrusion and solid-state drawing line. Two methodologies are explored to achieve such high strength transparent polyethylene films; i) the use of suitable additives like 2-(2H-benzotriazol-2-yl)-4,6-ditertpentylphenol (BZT) and ii) solid-state drawing at…
PrP (58–93) peptide from unstructured N-terminal domain of human prion protein forms amyloid-like fibrillar structures in the presence of Zn2+ ions
Gielnik, Maciej; Pietralik, Zuzanna; Zhukov, Igor; Szymańska, Aneta; Kwiatek, Wojciech M.; Kozak, Maciej
Many transition metal ions modulate the aggregation of different amyloid peptides. Substoichiometric zinc concentrations can inhibit aggregation, while an excess of zinc can accelerate the formation of cytotoxic fibrils. In this study, we report the fibrillization of the octarepeat domain to amyloid-like structures. Interestingly, this self-assembling process occurred only in…
Diversified α-phase nanostructure of isotactic polypropylene under cylindrical confinement via cross diffraction analysis
Zeng, Xingming; Zhang, Shuailin; Zheng, Nan; Yu, Shichen; Li, Xiaoguang; Ageishi, Masaki; Lotz, Bernard; Liu, Gengxin; Cao, Yan
Understanding polymer nanostructures is a prerequisite to manipulate their physical properties. Molecular self-assembly under confinement effectively generates novel polymer nanostructures. However, in one confined system, diffraction signals of different nanostructures are merged in a typical two-dimensional (2D) wide-angle X-ray diffraction (WAXD) measurement. For comparison, selected-area…