Temperature-dependence of dynamic rheological properties for high-density polyethylene filled with graphite

Dong, Qiqiong; Zheng, Qiang; Du, Ming; Zhang, Mingqiu

doi:10.1007/s10853-005-2885-8

Cited by 8 publications

(3 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…As shown in Figure 10c, the tan δ of the extruded straw/LLDPE melt showed a sharp peak at around 0.2 rad/s, whereas the hot pressed straw/LLDPE melt did not show a clear peak. In the G -ω curve, the tanδ peak appears along with the modulus platform; that is, the tanδ peak is also a characteristic of solid-like behavior [30]. The change in the value of tanδ indicates a change in viscoelasticity, thus demonstrating that the viscoelasticity of the hot pressed composite is fairly stable [31].As shown in Figure 10c, tanδ was less than 1 over the entire scanning frequency range, thus indicating that the straw/LLDPE melting exhibited elasticity.…”

Section: Dynamic Rheological Performance Analysismentioning

confidence: 99%

Performance of Straw/Linear Low Density Polyethylene Composite Prepared with Film-Roll Hot Pressing

Zhang

Wang

2020

Polymers

View full text Add to dashboard Cite

Thermoplastic composites are usually prepared with the extrusion method, and straw reinforcement material must be processed to fiber or powder. In this study, film-roll hot pressing was developed to reinforce linear low density polyethylene (LLDPE) with long continuous straw stems. The long straw stems were wrapped with LLDPE film and then hot pressed and cooled to prepare straw/LLDPE composite. Extruded straw fiber/LLDPE composite was prepared as a control. The mechanical properties of these LLDPE-based composites were evaluated. The hot pressed straw/LLDPE composite provided higher tensile strength, tensile modulus, flexural strength, flexural modulus, and impact strength than the traditional extruded straw/LLDPE composite, by 335%, 107%, 68%, 57%, and 181%, respectively, reaching 35.1 MPa, 2.65 GPa, 3.8 MPa, 2.15 GPa, and 25.1 KJ/m 2 . The density of the hot pressed straw/LLDPE composite (0.83 g/cm 3 ) was lower than that of the extruded straw/LLDPE composite (1.31 g/cm 3 ), and the former had a higher ratio of strength-to-weight. Scanning electron microscopy indicated that the orientation of the straws in the composite was better with the new method. Differential scanning calorimetry tests revealed that in hot pressed straw/LLDPE composite, straw fibers have a greater resistance to the melting of LLDPE than extruded composite. Rotary rheometer tests showed that the storage modulus of the hot pressed straw/LLDPE was less affected by frequency than that of the extruded composite, and the better elastic characteristics were pronounced at 150 • C. The hot pressed straw/LLDPE composite absorbed more water than the extruded composite and showed a potential ability to regulate the surrounding relative humidity. Our results showed that straw from renewable sources can be used to produce composites with good performance.Researchers have made some achievements in straw fiber reinforced composites. Nyambo et al. [7] used maleic acid-grafted polyurethane (PU-g-MA) to improve the interfacial adhesion between wheat straw and polyurethane (PU). They found that the addition of 3 phr and 5 phr PU-g-MA significantly increased the tensile strength (20%) and flexural strength (14%) of straw/PU composites, and proved that the increase in strength was due to the well combination of fibers and matrix. Xiao et al.[8] treated the straw with NaOH solution, blended the straw, polyethylene, stearic acid and maleic anhydride, then hot pressed to manufacture the straw/PP composite. The composite has low water absorption and good acid and alkali resistance; Zhang et al. [9] investigated the effects of different straw treatment methods, the particle size of straw powder, and the mass fraction of straw on the mechanical properties of straw/PP composites. The results show that when the straw is treated with the silane coupling agent KH570, the mechanical properties of the straw/PP composite are the best when the particle size of the straw powder is 60 mesh and the mass fraction is 50%; Zabihzadeh et al. [10] investigated the effect of maleic ...

show abstract

Section: Dynamic Rheological Performance Analysismentioning

confidence: 99%

Performance of Straw/Linear Low Density Polyethylene Composite Prepared with Film-Roll Hot Pressing

Zhang

Wang

2020

Polymers

View full text Add to dashboard Cite

show abstract

“…However, there are some drawbacks with Polyethylene including low environmental stress cracking resistance, low creep resistance, and poor compatibility with various additives which restricted its use for cretin purposes [6,7]. Therefore, there have been many attempts to improve the properties of polyethylene by blending it with organic or inorganic materials [6][7][8][9][10][11][12][13][14]. Among these materials is Ethylene Vinyl Acetate (EVA) copolymer, a member of the polyolefin family derived from random copolymerization of Vinyl Acetate (VA) and Ethylene.…”

Section: Introductionmentioning

confidence: 99%

Processing and Characterization of High Density Polyethylene/Ethylene Vinyl Acetate Blends with Different VA Contents

Alothman

2012

Advances in Materials Science and Engineering

View full text Add to dashboard Cite

Different series of high density Polyethylene/Ethylene Vinyl Acetate (HDPE/EVA) blends were prepared via melt blending in a corotating intermeshing twin screw extruder. The effects of VA percentage and EVA loading ratio on the thermal, rheological viscoelastic, mechanical, and fracture toughness of the blends were analyzed. The results showed that the addition of EVA to HDPE reduces the thermal, elastic, and viscoelastic properties of the blends. The microscopic examination of the fracture surface confirmed the ductile fracture of HDPE/EVA blends for all blend ratios and VA percentages. Increasing the EVA ratio and VA content caused a significant reduction in the blend crystallinity but had no significant effect on melting temperature. The complex viscosity increased with increasing the percentage of EVA due to the restriction of molecular mobility and reduction of free volume, induced by the addition of EVA. The storage modulus decreased with increasing the EVA ratio and temperature, while it increased with increasing the frequency. Young’s modulus, yield strength, and fracture strain decreased with increasing the EVA ratio. Similarly, the fracture toughness decreased proportional to the EVA percentage. Finally the results indicated that the VA content has significant effects on the mechanical, thermal, and dynamic properties of HDPE/EVA blends.

show abstract

“…High density polyethylene (HDPE) is a commodity thermoplastic polymer and is widely used in different applications due to its outstanding features such as regular chain structure, combination of low cost and low energy demand for processing, excellent biocompatibility, and good mechanical properties [1,2]. Properties of HDPE can be further manipulated by the addition of organic or inorganic particles into the polymer matrix [3,4]. The nanofiller reinforced HDPE composites have been studied for various fillers like nanoclay, metal oxide nano particles, and carbon nanotubes [5][6][7].…”

Section: Introductionmentioning

confidence: 99%

Effect of Modified and Nonmodified Carbon Nanotubes on the Rheological Behavior of High Density Polyethylene Nanocomposite

Adewunmi

Al-Juhani

Thomas

et al. 2013

Journal of Nanomaterials

View full text Add to dashboard Cite

This paper reports the results of studies on the rheological behavior of nanocomposites of high density polyethylene (HDPE) with pristine multiwall carbon nanotubes (CNT) as well as phenol and 1-octadecanol (C18) functionalized CNT at 1, 2, 3, 4, 5, and 7 wt% loading. The viscosity reduction at 1 wt% CNT follows the order, pristine CNT < phenol functionalized CNT < C18 functionalized CNT. As the filler loading increases from 1 to 2, 3, and 4 wt%, neat HDPE and filled HDPE systems show similar moduli and viscosity, particularly in the low frequency region. As the filler loading increases further to 5 and 7 wt%, the viscosity and moduli become greater than the neat HDPE. The storage modulus, tan, and the Cole-Cole plots show that CNT network formation occurs at higher CNT loading. The critical CNT loading or the rheological percolation threshold, where network formation occurs is found to be strongly dependant on the functionalization of CNT. For pristine CNT, the rheological percolation threshold is around 4 wt%, but for functionalized CNT it is around 7 wt%. The surface morphologies of CNT and functionalized CNT at 1 wt% loading showed good dispersion while at 7 wt% loading, dispersion was also achieved, but there are few regions with agglomeration of CNT.

show abstract

Temperature-dependence of dynamic rheological properties for high-density polyethylene filled with graphite

Cited by 8 publications

References 6 publications

Performance of Straw/Linear Low Density Polyethylene Composite Prepared with Film-Roll Hot Pressing

Performance of Straw/Linear Low Density Polyethylene Composite Prepared with Film-Roll Hot Pressing

Processing and Characterization of High Density Polyethylene/Ethylene Vinyl Acetate Blends with Different VA Contents

Effect of Modified and Nonmodified Carbon Nanotubes on the Rheological Behavior of High Density Polyethylene Nanocomposite

Contact Info

Product

Resources

About