Study of the rheological properties of polypropylene/talc/nanoclay ternary hybrid nano composites

AbstractModification of polypropylene (PP) properties by the addition of particulate fillers has been of interest for several years. In the recent years, the simultaneous use of nanofillers and conventional reinforcing fillers and study of the effect of these hybrid systems on various properties of composite has gained the attention of many researchers. In this paper, nanocomposites based on PP/Talc/Nanoclay were prepared at various filler levels via melt compounding of the ingredients in a twin-screw extruder. Here, a polypropylene grafted maleic anhydride (PP-g-MA)/Nanoclay master batch was prepared at 140 oC. The masterbatch was then used to prepare ternary compounds through a simultaneous feeding system, in a ZSK extruder at 210 °C. The extrudate was granulated and then re-extruded through a slit die, to prepare the test specimens. SEM and XRD analysis were used to characterise the systems. Rheological behaviour of the specimens was studied using a parallel plate rheometer. In the ternary blend on comparing with the neat PP, the complex viscosity (η*) is increased with increasing overall filler content; however, at low frequencies this increase is governed by the content of nano filler while at high frequencies it is mainly determined by talc content. A similar trend was also observed for the variations of storage modulus (G′) and loss modulus (G″) with frequency. The results showed that the simultaneous use of nano and micro size fillers considerably affects the melt elasticity. It is believed that the hybrid system increases the hydrodynamic effect of filler particles in the molecular motion of the polymer.

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Dynamic Rheology and Microstructure of Polypropylene/Clay Nanocomposites Prepared Under Sc-CO2 by Melt Compounding

Volume 13: Processing and Engineering Applications of Novel Materials ◽

10.1115/imece2007-43352 ◽

2007 ◽

Author(s):

Yang Zhao ◽

Han-Xiong Huang

Keyword(s):

Low Frequency ◽

Complex Viscosity ◽

Co2 Concentration ◽

Clay Nanocomposites ◽

X Ray Diffraction ◽

Melt Compounding ◽

Transmission Electron ◽

Nano Clay ◽

Twin Screw ◽

Negative Effect

The polypropylene (PP)/clay nanocomposites were prepared using a twin screw extruder with the aid of the supercritical carbon dioxide (Sc-CO2). The dynamic rheological properties were measured using a rheometer in the oscillatory mode. X-ray diffraction and transmission electron microscopy were used to characterize the microstructure of extruded nanocomposites. Results showed that an optimized CO2 concentration existed. When the CO2 concentration increased up to the optimized level, the nanocomposites tended to be more viscous, especially at low frequency. Whereas further increasing the CO2 concentration resulted in the decrease in the complex viscosity and dynamic moduli. The presence of Sc-CO2 with the concentration not higher than the optimized level was helpful to promote the degree of dispersion of the nano-clay in PP matrix, and overloaded CO2 would have negative effect on the clay dispersion.

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Anhydride/Epoxy Functionalized Blends: Mechanical, Rheological and Thermal Properties

MRS Proceedings ◽

10.1557/proc-702-u9.7.1 ◽

2001 ◽

Vol 702 ◽

Author(s):

Goknur Bayram ◽

Ulku Yilmazer

Keyword(s):

Thermal Properties ◽

Loss Modulus ◽

Complex Viscosity ◽

Chain Extension ◽

Screw Extruder ◽

Batch Mixing ◽

Twin Screw ◽

Styrene Maleic Anhydride ◽

Batch Mixer ◽

Fine Morphology

ABSTRACTBlends of styrene-maleic anhydride (SMAH) and polyethylene-methyl acrylate-glycidyl methacrylate (E-MA-GMA) were produced in a batch mixer and in a corotating twin screw extruder. E-MA-GMA concentration was varied from 0 % to 50 %. Batch mixing indicated that the blend system was reactive. Extruded blends were characterized in terms of rheological, thermal and mechanical properties, and their morphology was observed. Rheological properties such as the storage modulus, loss modulus and complex viscosity exhibited maxima at 25 % EMA-GMA content. The blends had fine morphology as observed by scanning electron microscopy. Thermal properties were not significantly affected by the change in epoxy concentration. As E-MA-GMA concentration increased, tensile strength and modulus of elasticity decreased, but percent strain at break increased. These observations could be explained in terms of the chain extension / branching reactions that occurred in mixing the blends.

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Shear Thickening Behaviour of Composite Propellant Suspension under Oscillatory Shear

Defence Science Journal ◽

10.14429/dsj.66.8849 ◽

2016 ◽

Vol 66 (3) ◽

pp. 222 ◽

Cited By ~ 3

Author(s):

D. Singh ◽

G. Dombe ◽

C. Bhongale ◽

P. P. Singh ◽

Mehilal Maurya ◽

...

Keyword(s):

Strain Amplitude ◽

Loss Modulus ◽

Shear Thickening ◽

Rheological Behaviour ◽

Complex Viscosity ◽

Solid Particles ◽

Dynamic Moduli ◽

Composite Propellant ◽

Plateau Region ◽

Temperature Constant

Composite propellant suspensions consist of highly filled polymeric system wherein solid particles of different sizes and shapes are dispersed in a polymeric matrix. The rheological behaviour of a propellant suspension is characterised by viscoplasticity and shear rate and time dependant viscosity. The behaviour of composite propellant suspension has been studied under amplitude sweep test where tests were performed by continuously varying strain amplitude (strain in %, γ) by keeping the frequency and temperature constant and results are plotted in terms of log γ (strain amplitude) vs logGʹ and logGʺ (Storage modulus and loss modulus, respectively). It is clear from amplitude sweep test that dynamic moduli and complex viscosity show marked increase at critical strain amplitude after a plateau region, infering a shear thickening behaviour.

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Rheological characterization of polymer-based nanocomposites with different nanoscale dispersions

e-Polymers ◽

10.1515/epoly.2005.5.1.38 ◽

2005 ◽

Vol 5 (1) ◽

Cited By ~ 7

Author(s):

Dong Gi Seong ◽

Tae Jin Kang ◽

Jae Ryoun Youn

Keyword(s):

Storage Modulus ◽

Extensional Flow ◽

Rheological Behaviour ◽

Polyamide 6 ◽

Twin Screw Extrusion ◽

Rheological Characterization ◽

Melt Compounding ◽

Transmission Electron ◽

Screw Extrusion ◽

Twin Screw

AbstractPolyamide 6 - clay nanocomposites with different nanoscale dispersions were prepared by melt compounding via twin-screw extrusion and their internal structures were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The rheological behaviour of these nanocomposites in shear and extensional flow were investigated using an Advanced Rheometric Expansion System and an Elongational Melts Rheometer in connection with the analysis by XRD and TEM. Nanocomposites with fully exfoliated structure and with poorly dispersed structure showed very different rheological behaviour. In general, addition of clay increased the viscosity and the storage modulus of nanocomposites, but different rheological behaviours were observed depending upon the degree of clay dispersion in the polymer matrix. In shear flow, only the exfoliated nanocomposite showed solid-like plateau behaviour in storage modulus and strong shear-thinning behaviour in shear viscosity. In extensional flow, only fully exfoliated nanocomposites showed strain-hardening behaviour, which is caused by the interaction between nanoparticles as well as between polymer molecules and nanoparticles.

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Fabrication and Characterization of Polypropylene/Ethylene-Octene Copolymer Blend Nanocomposites

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.29-30.267 ◽

2007 ◽

Vol 29-30 ◽

pp. 267-270 ◽

Cited By ~ 1

Author(s):

S.K. Samal ◽

S. Mohanty ◽

S.K. Nayak

Keyword(s):

Loss Modulus ◽

Clay Content ◽

Xrd Analysis ◽

X Ray Diffraction ◽

Rheological Characterization ◽

Maximum Increase ◽

Cloisite 30B ◽

Twin Screw ◽

The Impact ◽

Blend Nanocomposites

PP/EOC thermoplastic blend nanocomposites were prepared by melt intercalation technique using an intermeshing co-rotating twin screw extruder. The organoclay (Na+ MMT, Cloisite 20A, Cloisite 30B) content was varied between 0-5wt. % whereas the blend composition was kept constant (70PP: 30EOC) as optimized in our previous work. The effects of clays on the mechanical and rheological properties have been studied. Mechanical studies of PP/EOC nanocomposites reveal a significant increase in the impact strength upto a clay content of 3%. X-ray diffraction (XRD) analysis showed a significant increase in the interlayer gallery space with increase in clay loading. The rheological characterization made employing parallel plate rheometer revealed a maximum increase in storage modulus (G’) and loss modulus (G”) in case of modified clay indicating higher stiffness of the nanocomposites as compared to unmodified nanocomposites. Time Temperature superposition (TTS) was employed to generate various viscoelastic mastercurves.

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Characterizations of Polypropylene/Single-Walled Carbon Nanotube Nanocomposites Prepared by the Novel Melt Processing Technique with a Controlled Residence Time

Processes ◽

10.3390/pr9081395 ◽

2021 ◽

Vol 9 (8) ◽

pp. 1395

Author(s):

Dongho Kang ◽

Sungwook Hwang ◽

Bichnam Jung ◽

Jinkie Shim

Keyword(s):

Carbon Nanotubes ◽

Percolation Threshold ◽

Residence Time ◽

Loss Modulus ◽

Complex Viscosity ◽

Processing Technique ◽

Melt Processing ◽

Melt Mixing ◽

Single Walled Carbon ◽

Twin Screw

Melt processing is considered one of the favored techniques to produce polymer nanocomposites with various inorganic fillers such as graphene and carbon nanotubes (CNTs). Due to their superior conductivity and tensile properties, among others, CNTs have been applied in broad applications. When a low filler fraction is desired, a high degree of dispersion is required in order to benefit from the intrinsic properties of CNTs. However, due to their high cohesive energy, dispersing CNTs in polymer melts is a difficult task. This study employed the melt mixing technique with a controlled residence time of 20 min to disperse single-walled carbon nanotubes (SWNTs) into a polypropylene matrix. The composites were prepared by using a corotating twin-screw extruder equipped with a back-conveying element with varying amounts of SWNTs from 0.29 to 6.56 wt.%. Mechanical, electrical, morphological, and rheological properties were evaluated. Due to the filler effect, storage, loss modulus, and complex viscosity increased with the SWNT content. Based on the van Gurp–Palmen plot, 0.29 wt.% SWNTs was the rheological percolation threshold, and the electrical property measurement revealed a 1.4 wt.% SWNT electrical percolation threshold based on the statistical percolation theory. Relatively large agglomerates were found when the SWNT content increased more than 1.28 wt.%.

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Dynamic Rheological Properties of Concentrated Chitosan Soltions

Applied Rheology ◽

10.1515/arh-2004-0009 ◽

2004 ◽

Vol 14 (3) ◽

pp. 140-147 ◽

Cited By ~ 10

Author(s):

A. Martínez-Ruvalcaba ◽

E. Chornet ◽

D. Rodrigue

Keyword(s):

Storage Modulus ◽

Loss Modulus ◽

Complex Viscosity ◽

Maxwell Model ◽

Viscous Effects ◽

Experimental Conditions ◽

Low Frequencies ◽

Wide Range ◽

Generalized Maxwell Model ◽

Different Temperatures

AbstractA detailed analysis of the dynamic flow properties of chitosan in solution at different temperatures (25 - 45°C), chitosan concentration (0.5% - 2.0%), solvent type (acetic, lactic, and hydrochloric acid), and ionic strength (0 and 0.2M NaCl) has been undertaken. The storage modulus, G’, loss modulus, G’’ and complex viscosity, η* have been determined over a wide range of frequencies and the results are presented using master curves. For the conditions studied, at low frequencies chitosan solutions show a constant complex viscosity which decreases as frequency increases. Likewise, storage modulus, G’ and loss modulus, G’’ increase as frequency increases with G’’ being always greater than G’ (η’ > η’’) indicating that viscous effects are more important than elastic effects. For modelling the oscillatory-shear results we used the generalized Maxwell model. Two empirical equations were used to correlate the data: Cox-Merz rule for viscosity and Laun's rule for primary normal stress difference. Both relations were found to represent our data for the experimental conditions studied.

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Dynamic rheological behavior of polyfluorinated ethylene propylene/polypropylene blend melts

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705715598363 ◽

2016 ◽

Vol 30 (2) ◽

pp. 273-285 ◽

Cited By ~ 1

Author(s):

JZ Liang ◽

W Peng ◽

KJ Wang

Keyword(s):

Loss Modulus ◽

Weight Fraction ◽

Complex Viscosity ◽

Experimental Conditions ◽

Ethylene Propylene ◽

Twin Screw ◽

The Difference ◽

Tan Δ ◽

Pp Blends ◽

The Relationship

The polyfluorinated ethylene propylene (FEP)/polypropylene (PP) blend was compounded at melt state in a twin-screw extruder. The melt dynamic viscoelasticity of FEP/PP blends was measured using a Bohlin rheometer with the extended temperature option under experimental conditions with temperature scope from 270°C to 280°C and shear frequency ( ω) varying from 10−2 to 101 s−1. The results showed that the shear storage modulus ( G′) and shear loss modulus ( G″) increased nonlinearly, while the dynamic complex viscosity ( η*) decreased slightly with increasing ω. The G′ and G″ were an exponential function of ω. The G′, G″, and η* of the blend melts decreased with an addition of the PP weight fraction [Formula: see text], and the relationship between them might be expressed by a multinomial third-order equation. This phenomenon might be attributed to the difference in viscoelasticity between the FEP melt and PP melt. The value of tan δ of the blend melts achieved the maximum at about 100 s−1.

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Effect of SEBS-g-MAH addition on the mechanical, rheological, and morphological properties of polycarbonate/acrylonitrile–butadiene–styrene blends

Journal of Elastomers & Plastics ◽

10.1177/0095244317753652 ◽

2018 ◽

Vol 50 (7) ◽

pp. 611-633 ◽

Cited By ~ 12

Author(s):

Ismahane Debbah ◽

Rachida Krache ◽

Nora Aranburu ◽

Mercedes Fernández ◽

Agustin Etxeberria

Keyword(s):

Acrylonitrile Butadiene Styrene ◽

Complex Viscosity ◽

Morphological Properties ◽

Screw Extruder ◽

Elongation At Break ◽

Melt Compounding ◽

Twin Screw ◽

Poly Acrylonitrile ◽

Insight Into ◽

Butadiene Styrene

In this research, the effect of maleic anhydride–grafted styrene–ethylene/butylene–styrene (SEBS-g-MAH) compatibilizer on different properties of polycarbonate and poly(acrylonitrile–butadiene–styrene) (PC/ABS) blends was investigated. For this purpose, blends of PC and ABS at different ratios, without and with varying concentrations of compatibilizer, were prepared by melt compounding in a co-rotating twin-screw extruder followed by injection molding. The effectiveness of the compatibilizer was investigated by studying the microstructure and the mechanical, thermal, and rheological properties of the blends. It was found that the addition of the compatibilizer increases tensile strength, modulus, elongation at break, impact strength, complex viscosity, and thermal stability. This effect was noted at a loading of 1 wt% of compatibilizer, where enhanced interactions between the PC and ABS can be seen. Rheological methods, based on dynamic viscoelastic tests, allowed us to distinguish between emulsion-like and co-continuous morphologies and allowed an insight into the effect of the compatibilizer on the interfacial tension.

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Influence of κ-Carrageenan, Modified Starch and Inulin Addition on Rheological and Sensory Properties of Non-fat and Non-added Sugar Dairy Dessert

Current Nutrition & Food Science ◽

10.2174/1573401315666190301152645 ◽

2020 ◽

Vol 16 (4) ◽

pp. 462-469

Author(s):

Zhaleh Sheidaei ◽

Bahareh Sarmadi ◽

Seyede M. Hosseini ◽

Fardin Javanmardi ◽

Kianoush Khosravi-Darani ◽

...

Keyword(s):

Storage Modulus ◽

Loss Modulus ◽

Viscoelastic Behavior ◽

Textural Properties ◽

Complex Viscosity ◽

Sensory Properties ◽

Modified Starch ◽

Consumer Health ◽

Added Sugar ◽

Textural Parameters

Background: The high amounts of fat, sugar and calorie existing in dairy desserts can lead to increase the risk of health problems. Therefore, the development of functional and dietary forms of these products can help the consumer health. Objective: This study aims to investigate the effects of κ-carrageenan, modified starch and inulin addition on rheological and sensory properties of non-fat and non-added sugar dairy dessert. Methods: In order to determine the viscoelastic behavior of samples, oscillatory test was carried out and the values of storage modulus (G′), loss modulus (G″), loss angle tangent (tan δ) and complex viscosity (η*) were measured. TPA test was used for analysis of the desserts’ texture and textural parameters of samples containing different concentrations of carrageenan, starch and inulin were calculated. Results: All treatments showed a viscoelastic gel structure with the storage modulus higher than the loss modulus values. Increasing amounts of κ-carrageenan and modified starch caused an increase in G′ and G″ as well as η* and a decrease in tan δ. Also, firmness and cohesiveness were enhanced. The trained panelists gave the highest score to the treatment with 0.1% κ-carrageenan, 2.5% starch and 5.5% inulin (sucralose as constant = 0.25%) and this sample was the best treatment with desirable attributes for the production of non-fat and non-added sugar dairy dessert. Conclusion: It can be concluded that the concentration of κ-carrageenan and starch strongly influenced the rheological and textural properties of dairy desserts, whereas the inulin content had little effect on these attributes.

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