scholarly journals Extrusion Dwell Time and Its Effect on the Mechanical and Thermal Properties of Pitch/LLDPE Blend Fibres

Crystals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1520
Author(s):  
Salem Mohammed Aldosari ◽  
Sameer Rahatekar
Keyword(s):  
Tensile Strength ◽  
Dwell Time ◽  
Low Density Polyethylene ◽  
Mechanical And Thermal Properties ◽  
Low Density ◽  
Carbon Fibres ◽  
Linear Low Density Polyethylene ◽  
New Generation ◽  
Thermal Stability Of ◽  
Selection Of

Mesophase pitch-based carbon fibres have excellent resistance to plastic deformation (up to 840 GPa); however, they have very low strain to failure (0.3) and are considered brittle. Hence, the development of pitch fibre precursors able to be plastically deformed without fracture is important. We have previously, successfully developed pitch-based precursor fibres with high ductility (low brittleness) by blending pitch and linear low-density polyethylene. Here, we extend our research to study how the extrusion dwell time (0, 6, 8, and 10 min) affects the physical properties (microstructure) of blend fibres. Scanning electron microscopy of the microstructure showed that by increasing the extrusion dwell from 0 to 10 min the pitch and polyethylene components were more uniformly dispersed. The tensile strength, modulus of elasticity, and strain at failure for the extruded fibres for different dwell times were measured. Increased dwell time resulted in an increase in strain to failure but reduced the ultimate tensile strength. Thermogravimetric analysis was used to investigate if increased dwell time improved the thermal stability of the samples. This study presents a useful guide to help with the selection of mixes of linear low-density polyethylene/pitch blend, with an appropriate extrusion dwell time to help develop a new generation of potential precursors for pitch-based carbon fibres.

Effect of the blow-up ratio on morphology and engineering properties of three-layered linear low-density polyethylene blown films

2017 ◽  
Vol 34 (1) ◽  
pp. 27-42 ◽  
Author(s):  
Suthakarn Auksornkul ◽  
Siriwat Soontaranon ◽  
Chonthicha Kaewhan ◽  
Pattarapan Prasassarakich
Keyword(s):  
Electron Microscopy ◽  
Tensile Strength ◽  
Transverse Direction ◽  
Blow Up ◽  
Engineering Properties ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Film Morphology ◽  
Linear Low Density Polyethylene ◽  
Machine Direction

A series of linear low-density polyethylene films were produced using a three-layer co-extrusion machine. How the blow-up ratio and resin characteristics affected the final film morphology and engineering properties were studied. The crystalline morphology and orientation during the blown film process of the low-density polyethylene film were investigated using small-angle X-ray scattering, transmission electron microscopy and scanning electron microscopy. Increasing the blow-up ratio increased the transverse direction molecular orientation and decreased the machine direction orientation. The resulting low-density polyethylene morphology was a regular lamellar stacking parallel to the machine direction. The film morphology strongly influenced the mechanical properties. Increasing the blow-up ratio from 1.7 to 2.8 decreased the machine direction tensile strength by 14% and increased the transverse direction tensile strength up to 27% for both the low-density polyethylene/1-butene and low-density polyethylene/1-octene co-monomers, while the machine direction tear strength increased up to 36% and the transverse direction decreased by 16%. Moreover, the first and second heating characteristics from differential scanning calorimeter showed the inherent crystallinity change with increasing blow-up ratio for both the low-density polyethylene/1-octene and the low-density polyethylene/1-butene copolymer. The crystalline orientation changes induced with increasing blow-up ratio affected the film water vapor and oxygen permeability.

scholarly journals Effect of Heat Drawing Process on Mechanical Properties of Dry-Jet Wet Spun Fiber of Linear Low Density Polyethylene/Carbon Nanotube Composites

2017 ◽  
Vol 2017 ◽  
pp. 1-9
Author(s):  
Jong Won Kim ◽  
Joon Seok Lee
Keyword(s):  
Mechanical Properties ◽  
Plastic Deformation ◽  
Tensile Strength ◽  
Polymer Materials ◽  
Degree Of Crystallinity ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Drawing Process ◽  
Linear Low Density Polyethylene ◽  
Crystallinity Degree

Polyethylene is one of the most commonly used polymer materials. Even though linear low density polyethylene (LLDPE) has better mechanical properties than other kinds of polyethylene, it is not used as a textile material because of its plastic behavior that is easy to break at the die during melt spinning. In this study, LLDPE fibers were successfully produced with a new approach using a dry-jet wet spinning and a heat drawing process. The fibers were filled with carbon nanotubes (CNTs) to improve the strength and reduce plastic deformation. The crystallinity, degree of orientation, mechanical properties (strength to yield, strength to break, elongation at break, and initial modulus), electrical conductivity, and thermal properties of LLDPE fibers were studied. The results show that the addition of CNTs improved the tensile strength and the degree of crystallinity. The heat drawing process resulted in a significant increase in the tensile strength and the orientation of the CNTs and polymer chains. In addition, this study demonstrates that the heat drawing process effectively decreases the plastic deformation of LLDPE.

The Properties of Linear Low Density Polyethylene/Cyperus Odoratus (LLDPE/CY) Blends: Effect of Sodium Hydroxide

2015 ◽  
Vol 815 ◽  
pp. 69-73 ◽  
Author(s):  
Nik Ahmad Faris Nik Abdullah ◽  
Nik Noriman Zulkepli ◽  
Sam Sung Ting ◽  
Mohd Mustafa Al Bakri Abdullah ◽  
Kamarudin Hussin ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Sodium Hydroxide ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Natural Fibers ◽  
Biodegradable Plastics ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Linear Low Density Polyethylene ◽  
Naoh Solution

The purpose of this study was to determine the effect of treated Cyperus Odoratus (CY) with sodium hydroxide (NaOH) on the properties of biodegradable plastics made from linear low density polyethylene (LLDPE)/CY blends. Alkali treatments for natural fibers can increased adhesion between the hydrophilic fibers and hydrophobic matric. After CY was treated with 5% NaOH solution, it can be seen that the tensile strength and Young’s modulus of the LLDPE/CY blends significantly increased. Therefore, alkali treatments can be considered in modifying the properties of natural fibers.

scholarly journals Linear Low Density Polyethylene Filled with Almond Shells Particles: Mechanical and Thermal Properties

2019 ◽  
Vol 135 (5) ◽  
pp. 1042-1044 ◽  
Author(s):  
L. Altay ◽  
A. Guven ◽  
M. Atagur ◽  
T. Uysalman ◽  
G. Sevig Tantug ◽  
...  
Keyword(s):  
Thermal Properties ◽  
Low Density Polyethylene ◽  
Mechanical And Thermal Properties ◽  
Low Density ◽  
Linear Low Density Polyethylene

scholarly journals Influence of High-Concentration LLDPE on the Manufacturing Process and Morphology of Pitch/LLDPE Fibres

Crystals ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1099
Author(s):  
Salem Mohammed Aldosari ◽  
Muhammad A. Khan ◽  
Sameer Rahatekar
Keyword(s):  
Mechanical Properties ◽  
Thermal Stability ◽  
Tensile Modulus ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Linear Low Density Polyethylene ◽  
High Concentration ◽  
Scanning Electron Microscope Study ◽  
High Concentrations ◽  
Thermal Stability Of

A high modulus of elasticity is a distinctive feature of carbon fibres produced from mesophase pitch. In this work, we expand our previous study of pitch/linear low-density polyethylene blend fibres, increasing the concentration of the linear low-density polyethylene in the blend into the range of from 30 to 90 wt%. A scanning electron microscope study showed two distinct phases in the fibres: one linear low-density polyethylene, and the other pitch fibre. Unique morphologies of the blend were observed. They ranged from continuous microfibres of pitch embedded in linear low-density polyethylene (occurring at high concentrations of pitch) to a discontinuous region showing the presence of spherical pitch nodules (at high concentrations of linear low-density polyethylene). The corresponding mechanical properties—such as tensile strength, tensile modulus, and strain at failure—of different concentrations of linear low-density polyethylene in the pitch fibre were measured and are reported here. Thermogravimetric analysis was used to investigate how the increased linear low-density polyethylene content affected the thermal stability of linear low-density polyethylene/pitch fibres. It is shown that selecting appropriate linear low-density polyethylene concentrations is required, depending on the requirement of thermal stability and mechanical properties of the fibres. Our study offers new and useful guidance to the scientific community to help select the appropriate combinations of linear low-density polyethylene/pitch blend concentrations based on the required mechanical property and thermal stability of the fibres.

Tensile Properties LLDPE/Soya Spent Powder Blends: Oven Aging

2013 ◽  
Vol 795 ◽  
pp. 429-432
Author(s):  
S.T. Sam ◽  
N.Z. Noriman ◽  
S. Ragunathan ◽  
H. Ismail
Keyword(s):  
Tensile Strength ◽  
Tensile Properties ◽  
Aging Time ◽  
Thermal Aging ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Linear Low Density Polyethylene ◽  
Elongation At Break ◽  
Powder Blends ◽  
Internal Mixer

Linear low-density polyethylene (LLDPE)/soya spent powder blends with different blends ratio were prepared by using internal mixer. Soya spent powder was varied from 5 to 40 wt. The thermal degradability was assessed by subjecting the dumbbell sample to oven aging. Thermal aging was carried out for 5 weeks. The degradability was measured by the periodic change in tensile properties of the blend samples. The tensile strength and elongation at break of the blends reduced as increasing the aging time. The effect of degradation was obvious in higher soya spent powder blends.

Preparation and Characterization of Functionalized Graphene/Linear Low Density Polyethylene Nanocomposites

2010 ◽  
Vol 123-125 ◽  
pp. 173-176
Author(s):  
Tapas Kuila ◽  
Md Elias Uddin ◽  
Nam Hoon Kim ◽  
Gye Hyoung Yoo ◽  
Joong Hee Lee
Keyword(s):  
Xrd Analysis ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Functionalized Graphene ◽  
Linear Low Density Polyethylene ◽  
X Ray Diffraction ◽  
Elongation At Break ◽  
Pure Matrix ◽  
Thermal Stability Of

The present work deals with the functionalization of graphene sheet and preparation of functionalized graphene/linier low density polyethylene (LLDPE) nanocomposites by solution-mix techniques. Dodecyl amine (DA) has been used for the surface modification of graphene oxide (GO) and hydrazine as reducing agent. Fourier transform infrared (FTIR) spectra exhibits the appearance of new peaks in the functionalized graphene (DA-G), which suggests the functionalization of graphene by DA. X-ray diffraction (XRD) analysis infers the formation of fully exfoliated DA-G/LLDPE nanocomposites. The tensile strength (TS) and elongation at break (EB) of the composites are higher in comparison to neat LLDPE. The nanocomposites with only 0.5 wt.% of DA-G content results in TS and EB to be 17% and 10% higher compared to neat LLDPE. TGA shows that the thermal stability of the DA-G/LLDPE nanocomposites is higher compared to pure matrix polymer.

Reinforcing of low-density polyethylene by cellulose extracted from agricultural wastes

2018 ◽  
Vol 53 (2) ◽  
pp. 219-225 ◽  
Author(s):  
Shadi Sawalha ◽  
Raed Ma'ali ◽  
Omar Surkhi ◽  
Mohammad Sawalha ◽  
Bayan Dardouk ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Thermal Properties ◽  
Ultimate Tensile Strength ◽  
Solid Waste ◽  
Agricultural Wastes ◽  
Degree Of Crystallinity ◽  
Low Density Polyethylene ◽  
Mechanical And Thermal Properties ◽  
Low Density ◽  
Cellulosic Materials

Cellulosic materials were extracted from different agricultural wastes such as corn stalks, olive solid waste, and wood, by using a suitable extraction method. The extracted cellulosic materials were characterized using Fourier transform infrared spectroscopy. The produced cellulosic materials were used as reinforcements for low-density polyethylene to improve its tensile and thermal properties. A two-roll mill was used to mix the cellulosic materials (2.5–10 wt.%) with low-density polyethylene , and then the composite sheets were prepared by using a thermal press molding. The effects of filler type and its content on the mechanical and thermal properties were investigated by using the universal testing machine and differential scanning calorimeter, respectively. In general, with the increase of cellulosic materials content, there is an increase in the modulus of elasticity of the produced composites and a decrease of ductility. The ultimate tensile strength of the produced composites based on low-density polyethylene and cellulosic materials extracted from corn stalks and olive solid waste was found to be less than the tensile strength of low-density polyethylene, whereas the ultimate tensile strength of the composites based on low-density polyethylene and cellulose powder extracted from wood increased with increasing the cellulosic content. The addition of cellulosic materials was found to affect both the melting temperature of low-density polyethylene and its degree of crystallinity, depending on the cellulosic material source.

Characterization of Linear Low Density Polyethylene/Rambutan Peels Flour Blends: Effect of Loading Content

2016 ◽  
Vol 673 ◽  
pp. 171-179 ◽  
Author(s):  
A. Ainatun Nadhirah ◽  
S.T. Sam ◽  
N.Z. Noriman ◽  
Mohd Mustafa Al Bakri Abdullah ◽  
Mohd Firdaus Omar ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Tensile Properties ◽  
Testing Machine ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Linear Low Density Polyethylene ◽  
Screw Extruder ◽  
Twin Screw ◽  
Flour Blends

The effect of rambutan peels flour (RPF) content on the tensile properties of linear low density polyethylene filled with rambutan peel flour was studied. RPF was melt blended with linear low–density polyethylene (LLDPE). LLDPE/RPF blends were prepared by using twin screw extruder at 150°C with the flour content ranged from 0 to 25 wt%. The tensile properties were tested by using a universal testing machine (UTM) according to ASTM D638. The highest tensile strength was pure LLDPE meanwhile the tensile strength LLDPE/RPF decreased gradually with the addition of rambutan peels flour. Young’s modulus of rambutan peels flour filled LLDPE increased with increasing fiber loading. The crystallinity of the blends was significantly reduced with increasing RPF content. Instead, the water absorption increased with the addition of RPF content.

Sign in / Sign up

Export Citation Format

Share Document