Shen, Lihua; Severn, John; Bastiaansen, Cees W. M.
Drawing behavior and mechanical properties of ultra-high molecular weight polyethylene blends with a linear polyethylene wax
Ultra-high molecular weight polyethylene (UHMWPE; Mw = 103 kg/mol) is blended with a low molecular weight, linear polyethylene (PEwax; Mw = 1 kg/mol) and the solid state drawing behavior and mechanical properties are explored. The results indicate that the low molecular weight polyethylene wax acts as a solvent for the UHMWPE which leads to an improvement…
Structure-Properties Relations for Polyamide 6, Part 2: Influence of Processing Conditions during Injection Moulding on Deformation and Failure Kinetics
Parodi, Emanuele; Peters, Gerrit W. M.; Govaert, Leon E.
The effect of processing conditions during injection on the structure formation and mechanical properties of injection molded polyamide 6 samples was investigated in detail. A large effect of the mold temperature on the crystallographic properties was observed. Also the the effect of pressure and shear flow was taken in to…
Biodegradable Electrospun PLLA Fibers Containing the Mosquito-Repellent DEET
Bonadies, Irene; Longo, Alessandra; Androsch, René; Jehnichen, Dieter; Göbel, Michael; Laura Di Lorenzo, Maria
The manuscript details the first literature example of fibers of poly(l-lactic acid) (PLLA) containing a mosquito repellent agent, N,N-diethyl-3-methylbenzamide (DEET). The fibers were prepared by electrospinning, are defect-free and have uniform diameter of the order of magnitude of 1 µm. Thermogravimetry and infrared spectroscopy showed that it is possible to…
Improving adhesion between aramid fibers and natural rubber through morphological and synthetic modification of the fibers
Kanbargi, Nihal; Lesser, Alan J.
ABSTRACT In this article, we present new methods to improve the adhesion between poly(paraphenylene terephthalamide) fibers and a natural rubber for tire reinforcement. Fiber pretreatments are applied to create new surface morphologies on the fiber that enables enhanced adhesion between the fiber and rubber matrix. The pretreated fibers are then…
Polymer nanocomposites: Insights on rheology, percolation and molecular mobility
Nadiv, Roey; Fernandes, Ricardo M. F.; Ochbaum, Guy; Dai, Jing; Buzaglo, Matat; Varenik, Maxim; Biton, Ronit; Furó, István; Regev, Oren
The integration of carbon nanotubes (CNTs) into a polymer matrix strongly affects the rheological behavior that in turn may hamper the overall performance of the resulting composite. Research in this topic has focused on bulk rheological properties, while here we employ NMR diffusion experiments to explore the mobility (diffusivity) of…
Flow-Induced Crystallization of Polyamide-6
Flow-Induced Crystallization of Polyamide-6
Massaro, R.; Roozemond, P.; D’Haese, M.; Puyvelde, P. Van
Flow-Induced Crystallization of Polyamide-6
Massaro, R.; Roozemond, P.; D’Haese, M.; Puyvelde, P. Van
Flow-induced crystallization has been widely studied for a variety of polymers with the main focus on polyolefins. In this work, research has been conducted on the flow-induced crystallization of another important class of polymers, namely polyamides. Different polyamides-6 with varying molecular weight have been studied. At relatively modest values of…
Thermally cross-linked diaminophenylindane (DAPI) containing polyimides for membrane based gas separations
Dose, Michelle E.; Chwatko, Malgorzata; Hubacek, Ivo; Lynd, Nathaniel A.; Paul, Donald R.; Freeman, Benny D.
This study aims to expand structure-property relationships of diaminophenylindane (DAPI)-containing polyimides and the influence of thermal cross-linking on gas transport properties of such materials. A polyimide synthesized from hexafluoroisopropylidene diphthalic anhydride (6FDA), DAPI, and diaminobenzoic acid (DABA) in a molar ratio of 0.5/0.33/0.17, 6FDA0.5-DAPI0.33/DABA0.17, was crosslinked…
Homeotropic Self-Alignment of Discotic Liquid Crystals for Nanoporous Polymer Films
Lugger, Jody A. M.; Mulder, Dirk J.; Bhattacharjee, Subham; Sijbesma, Rint P.
Nanostructured polymer films with continuous, membrane-spanning pores from polymerizable hexagonal columnar discotic liquid crystals (LCs) were fabricated. A robust alignment method was developed to obtain homeotropic alignment of columns between glass surfaces by adding a small amount of a tri(ethylene glycol) modified analogue of the mesogen as a dopant that…
Progression of the Morphology in Random Ionomers Containing Bulky Ammonium Counterions
Enokida, Joshua S.; Tanna, Vijesh A.; Winter, H. Henning; Coughlin, E. Bryan
Poly(isoprene-ran-dimethyloctylammonium styrenesulfonate) (P(I-ran-DMOASS)) copolymers with high molecular weights and dimethyloctylammonium styrenesulfonate (DMOASS) compositions ranging between 8 and 40 mol % (30 and 77 wt %) were synthesized via nitroxide-mediated polymerization. Thermal and viscoelastic characterization revealed distinct behaviors for the low (30–51 wt %) and high (56–77 wt…
Photoluminescence enhancement via microwave irradiation of carbon quantum dots derived from solvothermal synthesis of L-arginine
Omer, Khalid M.; Aziz, Kosar H. Hama; Salih, Yousif M.; Tofiq, Diary I.; Hassan, Aso Q.
Photoluminescence enhancement of carbon quantum dots was achieved via solvothermal synthesis followed by microwave irradiation. Nitrogen and phosphorous doped carbon quantum dots were prepared by solvothermal heating of L-arginine with phosphoric acid for 12 hours followed by microwave irradiation for 3 minutes. The photoluminescence enhancement was nearly two fold after…