scholarly journals Novel results and potential applications of bitumen used as an additive for polyethylene

e-Polymers ◽  
2007 ◽  
Vol 7 (1) ◽  
Author(s):  
Goretti Goikoetxeaundia ◽  
Alexander Mateos ◽  
Oscar González ◽  
María Eugenia Muñoz ◽  
Anton Santamaría ◽  
...  

AbstractA metallocene catalysed linear low density polyethylene (mLLDPE) was mixed with very low amounts of bitumen (1-2%) as an additive. Bitumen interacts with mLLDPE giving rise to a dying effect, which turns the originally white mLLDPE extrudates into black. No slippage is observed during extrusion and sharkskin is postponed as bitumen is added. “Melt strength” values of the blends, determined in melt spinning experiments, are very similar to those of mLLDPE. Accordingly good performance is expected in film-blowing process. Tensile modulus values are higher than 109 Pa. Bitumen emerges as an alternative to carbon black powder currently used to obtain black polymer films.

2006 ◽  
Vol 312 ◽  
pp. 139-142 ◽  
Author(s):  
Qiang Yuan ◽  
Stuart Bateman ◽  
Dong Yang Wu

Stiff and tough conductive composites were manufactured using carbon black compounded with high and low density polyethylene, as well as linear low density polyethylene. A low percolation threshold value for the composites was achieved at 2 wt% carbon black. The impact strengths of the composites incorporating low density and linear low density polyethylene were found to be almost 16 and 26 times greater, respectively, than that of high density polyethylene composites. On the other hand, the modulus of high density polyethylene filled with carbon black was 2 times as high as low and linear low density polyethylene-based composites. Tensile modulus increased with the content of carbon black, however the impact strength of the composites decreased.


Polymer ◽  
2000 ◽  
Vol 41 (21) ◽  
pp. 7705-7713 ◽  
Author(s):  
Y Hong ◽  
S.J Coombs ◽  
J.J Cooper-White ◽  
M.E Mackay ◽  
C.J Hawker ◽  
...  

2020 ◽  
pp. 089270572094421
Author(s):  
Wagih Abdel Alim Sadik ◽  
Abdel Ghaffar Maghraby El Demerdash ◽  
Rafik Abbas ◽  
Alaa Bedir

The main goal of this work was to assess the technical feasibility of palm rachis (PR) as a reinforcing agent in the production of wood–plastic composites. Recycled linear low-density polyethylene/PR fiber composites were prepared at constant content (3 phc (per hundred compounds)) of maleic anhydride-grafted polyethylene as compatibilizer by melt blending method utilizing a two-roll mill and compression molding. The effect of nanosilica (NS), nanoclay (NC), and hybrid nanoparticles (NSNC) at different concentrations (2, 4, and 6 phc) on mechanical, physical, thermal, and morphological properties was investigated. The results of mechanical properties measurements demonstrated that when 6 phc NS, 4 phc NC, and 4 phc NSNC were added, tensile, modulus strength, and hardness reached their optimum values. At a high level of NC loading (6 phc), the increased populace of NC layers led to agglomeration and stress transfer gets restricted. Elongation at break and Izod impact strength were decreased by the incorporation of different nanoparticles. Water absorption and thickness swelling of prepared composites were found to decrease on the incorporation of NS and NC. In addition, the thermal stability showed slightly improved by the addition of nanoparticles, but there are no perceptible changes in the values of melting temperature by increasing the content of NS and NC or NSNC. Scanning electron microscopy study approved the good interaction of the PR fibers with the polymer matrix as well as the effectiveness of NS and NC in the improvement of the interaction. The finding indicated that wood–plastic composite treated by NS had the highest properties than other composites.


2002 ◽  
Vol 12 (3) ◽  
pp. 126-132 ◽  
Author(s):  
M. Zatloukal ◽  
J. Vlcek ◽  
A. Slaník ◽  
A. Lengálová ◽  
J. Simoník

Abstract A frequent problem in the production of metallocene linear low-density polyethylene (mLLDPE) films is the occur-rence of flow instabilities, e.g. sharkskin, or degradation of material, which limit the production rate and decrease the product quality. If such problems arise, the question is what causes these phenomena and how they can be avoided. With the aim of understanding these problems and providing some guidelines for their suppression, rheological measurements together with modelling of these melt flows are often employed. In the present study, flow behaviour of two commercially available mLLDPEs was determined and used for the process simulation. The paper shows that the capillary-rheology data together with 2D finite element method can be used for the prediction of sharkskin phenomenon as well as degradation of mLLDPE melts in film blowing dies. It also reveals that the degradation of the materials in these dies can be quantified through wall shear stress. Finally, the paper describes how these findings can help optimize the flow channel in the film blowing die to avoid the undesirable flow phenomena.


Crystals ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1099
Author(s):  
Salem Mohammed Aldosari ◽  
Muhammad A. Khan ◽  
Sameer Rahatekar

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.


2016 ◽  
Vol 1133 ◽  
pp. 156-160 ◽  
Author(s):  
Ai Ling Pang ◽  
Hanafi Ismail ◽  
Azhar Abu Bakar

Tensile properties and morphological studies of linear low density polyethylene (LLDPE)/poly (vinyl alcohol) (PVA)/kenaf (KNF) composites were investigated. The composites with different KNF loading (0, 10, 20, 30, 40 phr) were prepared using a Thermo Haake Polydrive internal mixer at 150°C and 50 rpm for 10 min. The results indicated that tensile strength and elongation at break were decreased with increasing KNF loading, whereas tensile modulus showed the opposite trend. Tensile fractured surfaces observed by scanning electron microscopy showed better interfacial adhesion between LLDPE/PVA and KNF at 10 phr KNF loading.


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