Characterization of Ceramic Batch Via Capillary Rheometry

1992 ◽  
Vol 289 ◽  
Author(s):  
Victor F. Janas ◽  
Christopher J. Malarkey ◽  
David R. Treacy ◽  
Michael E. Zak

AbstractRheological testing has been developed to predict the extrudability of ceramic pastes. Inorganic batches containing cellulosic binders were mixed in a twin screw extruder prior to characterization in a capillary rheometer. Various die lengths were used to separate viscosity from wall slip parameters. A power law model was fit to the paste viscosity. The wall shear stress, assuming 100% slip, was a linear function of the wall velocity. The resulting rheological models were used in fluid flow finite element analysis for determination of extrusion pressure, and the evaluation of binders.

Author(s):  
Dr. G. Kaemof

A mixture of polycarbonate (PC) and styrene-acrylonitrile-copolymer (SAN) represents a very good example for the efficiency of electron microscopic investigations concerning the determination of optimum production procedures for high grade product properties.The following parameters have been varied:components of charge (PC : SAN 50 : 50, 60 : 40, 70 : 30), kind of compounding machine (single screw extruder, twin screw extruder, discontinuous kneader), mass-temperature (lowest and highest possible temperature).The transmission electron microscopic investigations (TEM) were carried out on ultra thin sections, the PC-phase of which was selectively etched by triethylamine.The phase transition (matrix to disperse phase) does not occur - as might be expected - at a PC to SAN ratio of 50 : 50, but at a ratio of 65 : 35. Our results show that the matrix is preferably formed by the components with the lower melting viscosity (in this special case SAN), even at concentrations of less than 50 %.


2019 ◽  
pp. 089270571987822
Author(s):  
Saud Aldajah ◽  
Mohammad Y Al-Haik ◽  
Waseem Siddique ◽  
Mohammad M Kabir ◽  
Yousef Haik

This study reveals the enhancement of mechanical and thermal properties of maleic anhydride-grafted polypropylene (PP- g-MA) with the addition of nanocrystalline cellulose (NCC). A nanocomposite was manufactured by blending various percentages of PP, MA, and NCC nanoparticles by means of a twin-screw extruder. The influence of varying the percentages of NCC on the mechanical and thermal behavior of the nanocomposite was studied by performing three-point bending, nanoindentation, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and Fourier-transform infrared (FTIR) spectroscopy tests. The novelty of this study stems on the NCC nanoparticles and their ability to enhance the mechanical and thermal properties of PP. Three-point bending and nanoindentation tests revealed improvement in the mechanical properties in terms of strength, modulus, and hardness of the PP- g-MA nanocomposites as the addition of NCC increased. SEM showed homogeneity between the mixtures which proved the presence of interfacial adhesion between the PP- g-MA incorporated with NCC nanoparticles that was confirmed by the FTIR results. DSC and TGA measurements showed that the thermal stability of the nanocomposites was not compromised due to the addition of the coupling agent and reinforced nanoparticles.


Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 594
Author(s):  
Pavel Brdlík ◽  
Martin Borůvka ◽  
Luboš Běhálek ◽  
Petr Lenfeld

The influence of additives such as natural-based plasticiser acetyl tributyl citrate (ATBC), CaCO3 and lignin-coated cellulose nanocrystals (L-CNC) on the biodegradation of polylactic acid (PLA) biocomposites was studied by monitoring microbial metabolic activity through respirometry. Ternary biocomposites and control samples were processed by a twin-screw extruder equipped with a flat film die. Commonly available compost was used for the determination of the ultimate aerobic biodegradability of PLA biocomposites under controlled composting conditions (ISO 14855-1). In addition, the hydro-degradability of prepared films in a freshwater biotope was analysed. To determine the efficiency of hydro-degradation, qualitative analyses (SEM, DSC, TGA and FTIR) were conducted. The results showed obvious differences in the degradation rate of PLA biocomposites. The application of ATBC at 10 wt.% loading increased the biodegradation rate of PLA. The addition of 10 wt.% of CaCO3 into the plasticised PLA matrix ensured an even higher degradation rate at aerobic thermophilic composting conditions. In such samples (PLA/ATBC/CaCO3), 94% biodegradation in 60 days was observed. In contrast, neat PLA exposed to the same conditions achieved only 16% biodegradation. Slightly inhibited microorganism activity was also observed for ternary PLA biocomposites containing L-CNC (1 wt.% loading). The results of qualitative analyses of degradation in a freshwater biotope confirmed increased biodegradation potential of ternary biocomposites containing both CaCO3 and ATBC. Significant differences in the chemical and structural compositions of PLA biocomposites were found in the evaluated period of three months.


2008 ◽  
Vol 49 (4) ◽  
pp. 631-640 ◽  
Author(s):  
Katja Nevalainen ◽  
Jyrki Vuorinen ◽  
Vesa Villman ◽  
Reija Suihkonen ◽  
Pentti Järvelä ◽  
...  

2011 ◽  
Vol 71-78 ◽  
pp. 640-643
Author(s):  
Ming Zhao ◽  
Xiao Zhong Lu ◽  
Kai Gu ◽  
Xiao Min Sun ◽  
Chang Qing Ji

A series of polypropylene/ethylene-propylene-diene monomer / calcium silicate (PP/EPDM/CaS) composites with different contents was prepared by melt processing using a twin-screw extruder. The composites were characterized. The results showed the particle shape of calcium silicate is honeycomb structure . The heat deflection temperature of PP/EPDM/CaS composite increased with increasing CaS content. The composites had highest tensile strength and the lowest when CaS content was 9.5 phr and 35 phr respectively.


2014 ◽  
Vol 1025-1026 ◽  
pp. 241-245 ◽  
Author(s):  
Ľudmila Dulebová ◽  
Emil Spišák ◽  
Branislav Duleba ◽  
František Greškovič ◽  
Tomasz Garbacz

The paper presents the impact of the use of fillers on the mechanical properties of composites with polymeric matrix from polypropylene (PP). Two main types of mineral fillers - talc and calcium carbonate - were used for experiments. PP composites of different percentage filler in matrix PP were compounded with twin-screw extruder and then injection molding. Properties of composites were investigated by tensile test and thermal analysis. Tensile strength was performed to determine and compare the mechanical properties of the unfilled PP and filled PP with various percentages of fillers. Thermal analysis by thermogravimetric was performed on the tested materials - weight loss, glass transition temperature, thermal decomposition, melting temperature.


2007 ◽  
Vol 539-543 ◽  
pp. 948-955 ◽  
Author(s):  
Kenji Tamura ◽  
Hikaru Uno ◽  
Hirohisa Yamada

The effect of natural mica on the morphology and properties of polyamide 6 (PA-6) nanocomposites was examined. Natural mica (sericite) acquired from a well-known mine in Shimane, Japan was ion-exchanged with an alkyl amine hydrochloride compound. The resulting organomica was extruded with PA-6 using a twin-screw extruder. Quantitative analysis of TEM photomicrographs of the nanocomposite reveal a fairly large average particle length and a higher degree of platelet exfoliation for the natural mica-based nanocomposite compared to the clay version, thus translating into a higher particle aspect ratio. The resulting nanomica/PA-6 composite exhibits a high degree of mica exfoliation and improved thermal mechanical properties.


Sign in / Sign up

Export Citation Format

Share Document