Boopathi, A. A.; Sampath, Srinivasan; Narasimhaswamy, T.
Isothermal and non-isothermal cold crystallization of tetrabenzofluorene (TBF) molecules
Design and synthesis of tetrabenzofluorene (TBF) derivatives are carried out to investigate the isothermal and non-isothermal cold crystallization (CC) behavior by various spectroscopic and analytical techniques. The unprecedented CC exhibited by TBF molecules is examined by systematic modification of alkyl chain length (C8–C18 even carbons) on both sides of the…
Core-crystalline nanoribbons of controlled length via diffusion-limited colloid aggregation
Schmarsow, Ruth N.; Ceolín, Marcelo; Zucchi, Ileana A.; Schroeder, Walter F.
It has been previously reported that poly(ethylene) (PE)-based block copolymers self-assemble in certain thermosetting matrices to form a dispersion of one-dimensional (1D) nanoribbons. Such materials exhibit exceptional properties that originate from the high aspect ratio of the elongated nano-objects. However, the ability to prepare 1D assemblies with well-controlled dimensions is…
Hierarchical Sticker and Sticky Chain Dynamics in Self-Healing Butyl Rubber Ionomers
Mordvinkin, Anton; Suckow, Marcus; Böhme, Frank; Colby, Ralph H.; Creton, Costantino; Saalwächter, Kay
We present a detailed comparison of the microscopic dynamics and the macroscopic mechanical behavior of novel butyl rubber ionomers with tunable dynamics of sparse sticky imidazole-based sidegroups that form clusters of about 20 units separated by essentially unperturbed chains. This material platform shows promise for application as self-healing elastomers. Size…
Millimeter-Scale Unipolar Transport in High Sensitivity Organic–Inorganic Semiconductor X-ray Detectors
Jayawardena, K. D. G. Imalka; Thirimanne, Hashini M.; Tedde, Sandro Francesco; Huerdler, Judith E.; Parnell, Andrew J.; Bandara, R. M. Indrachapa; Mills, Christopher A.; Silva, S. Ravi P.
Hybrid inorganic-in-organic semiconductors are an attractive class of materials for optoelectronic applications. Traditionally, the thicknesses of organic semiconductors are kept below 1 μm due to poor charge transport in such systems. However, recent work suggests that charge carriers in such organic semiconductors can be transported over centimeter length scales opposing…
Effect of Irradiation and Detection of Long-Lived Polyenyl Radicals in Highly Crystalline Ultra-High Molar Mass Polyethylene (UHMMPE) Fibers
Forster, Amanda L.; Tsinas, Zois; Al-Sheikhly, Mohamad
To improve properties such as thermal conductivity, low temperature thermal strain, and creep resistance of ultra-high molar mass polyethylene (UHMMPE) fibers, several researchers have previously undertaken efforts to crosslink these fibers using radiation. Ionizing radiation is commonly used to crosslink bulk UHMMPE in other applications, such as artificial joints. However,…
Morphology and ionic conductivity relationship in silk/cellulose biocomposites
Blessing, Bailey; Trout, Cory; Morales, Abneris; Rybacki, Karleena; Love, Stacy A.; Lamoureux, Guillaume; O’Malley, Sean M.; Hu, Xiao; Cruz, David Salas-de la
The relationship between morphology and the ionic conductivity of polysaccharide–protein bio-electrolyte membranes is explored in this study. Structural proteins and polysaccharides form hydrophobic and electrostatic interactions, and the resulting matrices can exhibit novel and useful properties. However, transforming these natural biomacromolecules from their native state to a more usable form…
3D-Printing of Pure Metal–Organic Framework Monoliths
Lim, Gwendolyn J. H.; Wu, Yue; Shah, Bhuvan B.; Koh, J. Justin; Liu, Connie K.; Zhao, Dan; Cheetham, Anthony K.; Wang, John; Ding, Jun
Metal–organic frameworks (MOFs) are usually synthesized in powder form. For many practical applications, MOFs need to be shaped into monoliths that can be easily handled. However, conventional shaping methods, such as pelletization, often result in a decrease in functionality. Recently, MOF-containing monoliths have been made using direct ink writing (DIW;…
Ion transport, polarization and electro-responsive elelctrorheological effect of self-crosslinked poly(ionic liquid)s with different counterions
Liu, Yang; Zhao, Jia; He, Fang; Zheng, Chen; Lei, Qi; Zhao, Xiaopeng; Yin, Jianbo
Self-crosslinked bis(imidazolium)-based poly(ionic liquid)s (PILs) containing different counterions (P, X = BF4−, PF6−, TfO−, TFSI−) are synthesized and the influence of counterions on electro-responsive electrorheological (ER) effect is studied in order to understand the structure-property relationship of crosslinked PIL-based ER system. It is found that the size and type of…
Construction of Dual Orientation Crystalline Structure in Poly(vinyl alcohol)/Graphene Oxide Nano-Composite Hydrogels and Reinforcing Mechanism
Meng, Yeqiao; Zhao, Xiaowen; Ye, Lin
Oriented poly(vinyl alcohol) (PVA)/graphene oxide (GO) nanocomposite hydrogels with different draw ratios were prepared by stretching during a freezing/thawing process. The PVA/GO samples with a draw ratio of 200% had significantly enhanced mechanical properties by formation of a microfibrillar structure, while the tensile strength and compressive modulus respectively reached as…
Dielectric and flash DSC investigations on an epoxy based nanocomposite system with MgAl layered double hydroxide as nanofiller
Szymoniak, Paulina; Li, Zhi; Wang, De-Yi; Schönhals, Andreas
Nanocomposites based on MgAL layered double hydroxides (LDH) and an epoxy resin were prepared and investigated by a combination of complementary methods. As epoxy resin Bisphenol A diglycidyl ether (DGEBA) was used with Diethylenetriamine as curing agent. The LDH was modified with taurine, which acts as an additional crosslinking agent…