The effect of the addition of a slip agent on the rheological properties of polyethylene: off-line and in-line measurements

2019 ◽  
Vol 39 (5) ◽  
pp. 422-431 ◽  
Author(s):  
Arkadiusz Kloziński ◽  
Paulina Jakubowska
Keyword(s):  
Rheological Properties ◽  
Power Law ◽  
Extrusion Process ◽  
Low Density Polyethylene ◽  
Rheological Parameters ◽  
Low Density ◽  
Polymer Modification ◽  
Modified Polymer ◽  
Extrusion Head ◽  
Slip Agent

Abstract The article describes an investigation into the effect of a slip agent on the rheological properties of low-density polyethylene. As a slip modifier, oleamide was used in the amounts of 0.5, 1.0, 2.0, 3.0 and 4.0 wt.%, respectively. The process of polymer modification was carried out in a twin-screw extrusion process. The effect of the slip agent on the mass flow rate index was determined. The specific plasticisation energy of the modified polymer was also assessed based on the change in the torque of a batch mixer. The assessment of the effect of the addition of oleamide on the change in the flow and viscosity curves was made using an off-line (plastometer) and an in-line (extruder rheometer) measuring technique. The rheological parameters were determined based on the Ostwald-de-Waele power law model. The operation of the plastometer was brought closer to the principles of operation of the capillary rheometer by applying variable piston loading. In in-line measurements, an extrusion head with replaceable cylindrical dies was used. Using two rheological measuring techniques made it possible to determine the low-density polyethylene viscosity variations and the values of flow power law index (n) and consistency factor (K) in a wide shear rate range.

A Comparison of Rheological Models and Experimental Data of Metallocene Linear Low Density Polyethylene Solutions as a Function of Temperature and Concentration

2016 ◽  
Vol 12 (3) ◽  
pp. 4322-4339
Author(s):  
Salah Hamza
Keyword(s):  
Experimental Data ◽  
Shear Rate ◽  
Rheological Properties ◽  
Power Law ◽  
Low Density Polyethylene ◽  
Effect Of Temperature ◽  
Low Density ◽  
Linear Low Density Polyethylene ◽  
Shear Rates ◽  
Wide Range

Knowledge of rheological properties of polymer and their variation with temperature and concentration have been globally important for processing and fabrication of polymers in order to make useful products. Basheer et al. [1] investigated, experimentally, the changes in rheological properties of metallocene linear low density polyethylene (mLLDPE) solutions by using a rotational rheometer model AR-G2 with parallel plate geometry. Their work covered the temperature range from  to  and  concentration from  to . In this paper, we reconsider Basheer work to describe the rheological behavior of mLLDPE solutions and its dependence on concentration and temperature.Until now, several models have been built to describe the complex behavior of polymer fluids with varying degrees of success. In this article, Oldroyd 4-constant, Giesekus and Power law models were tested for investigating the viscosity of mLLDPE solution as a function of shear rate. Results showed that Giesekus and power law models provide the best prediction of viscosity for a wide range of shear rates at constant temperature and concentration. Therefore, Giesekus and power law models were suitable for all mLLDPE solutions while Oldroyd 4-constant model doesn't.A new proposed correlation for the viscosity of mLLDPE solutions as a function of shear rate, temperature and concentration has been suggested. The effect of temperature and concentration can be adequately described by an Arrhenius-type and exponential function respectively. The proposed correlation form was found to fit the experimental data adequately.

Characterization of Rheological Properties of Low Density Polyethylene in Torque Rheometers

2013 ◽  
Vol 804 ◽  
pp. 216-221
Author(s):  
Xiao Xia Jian ◽  
Wei Liang Zhou ◽  
Le Qin Xiao ◽  
Xiu Li Hu ◽  
Qi Long Zheng
Keyword(s):  
Rheological Properties ◽  
Apparent Viscosity ◽  
Test Methods ◽  
Low Density Polyethylene ◽  
Rheological Parameters ◽  
Low Density ◽  
Rotor Speed ◽  
Filling Degree ◽  
Polymer Melting ◽  
Power Rate

A method to evaluate the rheological properties of low density polyethylene (LDPE) using torque rheometer was developed and the parameter of Power rate model were obtained by fitting balance torque and balance temperature. The rheological parameters of polymer melts were evaluated on the basis of previous equation by introducing the apparent filling degree in torque rheometer, the results show the temperature compensated torque (Mtc) increase from 5.685 Nm to 6.972 Nm, while apparent filling degree change from 0.65 to 0.85 at the rotor speed of 29.98 rpm. TheMtcalso increase from 2,900 Nm to 3.528 Nm and increase by 0.628 Nm at the rotor speed of 4.985 rpm, while it increase by 1.287 Nm from 5.685 Nm to 6.972 Nm at the rotor speed of 29.99 rpm, which means the higher the rotor speed, the more influence on the torque. The other relative rheological parameters, such as the activation energy (ΔE), the Non-Newton (n), etc., calculated in this model, indicate the effect of apparent filling degree on the polymer melting rheology. The calculated values were compared with those derived from capillary rheolometer, the results show the apparent viscosity decrease with the increase shear rate in exponential function, the change rules of apparent viscosity are good agreement from two kinds test methods.

scholarly journals Protective Low-Density Polyethylene Residues from Prepreg for the Development of New Nanocomposites with Montmorillonite: Recycling and Characterization

Recycling ◽  
2019 ◽  
Vol 4 (4) ◽  
pp. 45
Author(s):  
Pamela Rodrigues Passos Severino ◽  
Thaís Larissa do Amaral Montanheiro ◽  
Orestes Ferro ◽  
Fábio Roberto Passador ◽  
Larissa Stieven Montagna
Keyword(s):  
Carbon Fiber ◽  
Extrusion Process ◽  
Morphological Properties ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Primary Role ◽  
Protective Films ◽  
And Storage ◽  
Compatibilizer Agent ◽  
The Ideal

A sustainable alternative to the destination of polyethylene (PE) residue from the prepreg package was established. This work intends to develop nanocomposites for packaging containing neat low-density polyethylene (LDPE), a compatibilizer agent (maleic anhydride grafted-LDPE, LDPE-g-MA), recycled LDPE obtained from the protective films of prepreg (rLDPE) and montmorillonite (MMT). The rLDPE, from the prepreg shield, has a primary role during the transport and storage of prepreg, which can be composed of epoxy resin and carbon fiber or glass fiber. However, this rLDPE is withdrawn and discarded, besides, it is estimated that tons of this material are discarded monthly by the company Alltec Materiais Compostos Ltd. (São José dos Campos-SP, Brazil). Due to several factors, including the lack of technology for recycling, the majority of this material is incinerated. In this context, this work presents a technical and ecologically viable alternative for the use of this discarded material. Nanocomposites of LDPE/rLDPE blends and montmorillonite (MMT) with different contents (0.0, 1.0, and 3.0 wt%) and with the addition of compatibilizer agent (LDPE-g-MA) were prepared by extrusion process. Test specimens were obtained by hot pressing in a hydropneumatic press followed by die-cutting. The nanocomposites produced using rLDPE presented good mechanical, thermal, and morphological properties, being the ideal concentration of 1 wt% MMT. Thus, the results obtained confirmed the viability of recycling LDPE from the prepreg package which contributes to the reduction of waste and the use of this material in technological applications.

scholarly journals Electrical, thermal and rheological properties of low-density polyethylene/ethylene vinyl acetate/graphene-like composite

2019 ◽  
Vol 177 ◽  
pp. 107288 ◽  
Author(s):  
Sohrab Azizi ◽  
Claudiane M. Ouellet-Plamondon ◽  
Phuong Nguyen-Tri ◽  
Michel Fréchette ◽  
Eric David
Keyword(s):  
Rheological Properties ◽  
Vinyl Acetate ◽  
Ethylene Vinyl Acetate ◽  
Low Density Polyethylene ◽  
Low Density
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