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

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.

2015 ◽  
Vol 37 (11) ◽  
pp. 3167-3174 ◽  
Author(s):  
S. Sánchez-Valdes ◽  
E. Ramírez-Vargas ◽  
L.F. Ramos de Valle ◽  
J.G. Martinez-Colunga ◽  
J. Romero-Garcia ◽  
...  

2020 ◽  
Vol 15 (3) ◽  
pp. 44-49
Author(s):  
Ibiyemi A. Idowu ◽  
Olutosin O. Ilori

The study examined the effect of fillers on the mechanical properties of the recycled low density polyethylene composites under weathered condition with a view of managing the generation and disposal of plastic wastes. Discarded pure water sachets and fillers (glass and talc) were sourced and recycled. Recycled low density polyethylene (RLDPE) and preparation of RLDPE/glass, RLDPE/talc and RLDPE/glass/talc composites were carried out using a furnace at compositions of 0 – 40% in steps of 10% by weight. The mixtures were poured into hand-laid mould. The samples produced were exposed to sunlight for eight (8) weeks and their mechanical properties were studied. The results of mechanical tests revealed that tensile strength decreased with increasing filler loading while impact strength and hardness property increased marginally and considerably with increasing filler loading for all the composites respectively. The study concluded that glass and talc were able to reinforce recycled low density polyethylene under weathered condition. Keywords: Recycled Low Density Polyethylene (RLDPE); Fillers; Glass, Talc; Weathering condition; Sunlight; and Mechanical properties; Tensile strength, Impact and hardness


2011 ◽  
Vol 43 (6) ◽  
pp. 543-558 ◽  
Author(s):  
Z. Chen ◽  
S. Chen ◽  
J. Zhang

The surfactant, sodium dodecylbenzenesulfonate (NaDDBS) and coupling agents, γ-aminopropyltriethoxy sliane (KH550) and isopropyl dioleic(dioctylphosphate) titanate (NDZ101) were used to treat multiwalled carbon nanotubes in this work. The effects of surface modification of multiwalled carbon nanotubes on crystallization behavior, mechanical properties, and electrical properties of low density polyethylene/polyolefin elastomer/multiwalled carbon nanotubes composites were studied. The results showed that NaDDBS, KH550, and NDZ101 had a favorable effect of improving the dispersion of multiwalled carbon nanotubes, but it cannot improve the interfacial interactionbetween multiwalled carbon nanotubes and the matrix. The improvement in dispersion favored the crystallization behavior and mechanical properties. Modified multiwalled carbon nanotubes had a better acceleration nucleation effect than raw multiwalled carbon nanotubes on low density polyethylene/polyolefin elastomer blends at low content (≤1 wt%). The tensile strength of low density polyethylene/polyolefin elastomer/multiwalled carbon nanotubes composites with modified multiwalled carbon nanotubes increased with lower multiwalled carbon nanotubes content (≤1 wt%), and KH550 and NDZ101 led low density polyethylene/polyolefin elastomer/multiwalled carbon nanotubes composites to possess a higher tensile strength than that of NaDDBS with 1 wt% content. NaDDBS, KH550, and NDZ101 had a minor influence on the dielectric properties of the composites and even caused a decrease in the dielectric loss of composites with 10 wt% multiwalled carbon nanotubes content.


2017 ◽  
Vol 34 (1) ◽  
pp. 27-42 ◽  
Author(s):  
Suthakarn Auksornkul ◽  
Siriwat Soontaranon ◽  
Chonthicha Kaewhan ◽  
Pattarapan Prasassarakich

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.


2019 ◽  
Vol 2019 ◽  
pp. 1-8
Author(s):  
Yilong Han ◽  
Songbai Xue ◽  
Renli Fu ◽  
Lihao Lin ◽  
Zhongqiang Lin ◽  
...  

This work focused on the influence of hydrogen content on the microstructure and mechanical properties of ER5183 Al-Mg-Mn alloy wires for aluminum alloy welding. The hydrogen content of the ER5183 wires was measured, the macroscopic and microscopic morphologies of fractures were observed as well as the microstructure of the wires, and the tensile strength of the wires was also tested and investigated. The experimental results demonstrated three typical irregular macroscopic fractures of the wires appeared during the drawing process when the hydrogen content exceeded 0.23 μg/g. In the meantime, the aggregated pores were observed in the microstructure of the ϕ5.2 mm wire with the hydrogen content of 0.38 μg/g. Such defects may become the origin of cracks in subsequent processing and tensile tests. Moreover, higher hydrogen content in the ϕ5.2 mm welding wire will bring obvious changes in the fracture surface, which are internal cracks and micropores replacing the original uniform and compact dimples. With the higher hydrogen content, the tensile strength and plastic strain rate of ϕ1.2 mm wires would decrease. At the same time, unstable crack propagation would occur during the process of plastic deformation, leading to fracture. Considering the mechanical properties and microstructure, the hydrogen content of the ER5183 wires should be controlled below 0.23 μg/g.


2020 ◽  
Vol 10 (6) ◽  
pp. 771-779
Author(s):  
Jing Deng ◽  
Qi Jue Chen ◽  
Ding Jie Chen ◽  
Luo Jie Zheng ◽  
Wen Li ◽  
...  

The aim of this research was to probe the potential application of nano-titanium dioxide (TiO2)/basic magnesium hypochlorite (BMH)-containing linear low-density polyethylene (LLDPE) composite film in grape fresh-keeping. Mechanical properties, transparency, barrier performance and antibacterial activity of the nano-composite membrane were measured, and results showed that the antibacterial zone diameter of TiO2/BMH on pathogen-Aspergillus niger was 31.4 mm, with mixing ratio of BMH/TiO2 to 2:1. It was clearly shown that the synthesized nano-composite films decreased mechanical properties and transparency of the membrane, and also had a significant impact on sensory score, mass loss rate, decay rate, ascorbic acid (Vc) content and titratable acid content compared with LLDPE films. Moreover, the results revealed that the LLDPE antibacterial film can be effectively used for storing grapes, preserving the flavor of grapes and had an obviously effect in prolonging grapes’ shelf life.


Sign in / Sign up

Export Citation Format

Share Document