Effects of relaxation time and zero shear viscosity on structural evolution of linear low-density polyethylene in shear flow

2017 ◽  
Vol 135 (13) ◽  
pp. 46053 ◽  
Author(s):  
Kun Li ◽  
Go Matsuba
Keyword(s):  
Relaxation Time ◽  
Shear Flow ◽  
Shear Viscosity ◽  
Structural Evolution ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Linear Low Density Polyethylene ◽  
Zero Shear Viscosity

scholarly journals The optimization of Carreau model and rheological behavior of alumina/linear low-density polyethylene composites with different alumina content and diameter

e-Polymers ◽  
2021 ◽  
Vol 21 (1) ◽  
pp. 742-753
Author(s):  
Guo Li ◽  
Mitao Zhang ◽  
Huajian Ji ◽  
Yulu Ma ◽  
Tao Chen ◽  
...  
Keyword(s):  
Particle Diameter ◽  
Low Density Polyethylene ◽  
Average Particle ◽  
Low Density ◽  
Linear Low Density Polyethylene ◽  
Carreau Model ◽  
Zero Shear Viscosity ◽  
Melt Mixing ◽  
Sem Images ◽  
Parameter Values

Abstract The influence of alumina (Al2O3) content and diameter on the viscosity characteristics of the alumina/linear low-density polyethylene (Al2O3/LLDPE) composites was discussed. The composites were fabricated by melt mixing with the two-rotor continuous mixer. The equivalent surface average particle diameter ( d ¯ A {\bar{d}}_{\text{A}} ) of Al2O3 was calculated by the scanning electron microscopic (SEM) images of samples. The steady-state and dynamic rheological measurements were used to study the evolution of viscosity parameters. With the Carreau model fitting to the steady-rate rheological data, zero-shear viscosity η 0, time constant λ, and power law index n of composites were obtained. On this basis, an optimized Carreau model was established by studying the changes of these parameter values. The rheological result presented that the parameter values (η 0, λ, and n) were linearly proportional to the filling content of Al2O3 particles for nano-Al2O3/LLDPE composites. However, these parameters were, respectively, related to d ¯ A {\bar{d}}_{\text{A}} , d ¯ A 2 {\bar{d}}_{\text{A}}^{2} , and d ¯ A 3 {\bar{d}}_{\text{A}}^{3} for micron-Al2O3/LLDPE composites.

scholarly journals Identification of the LLDPE Constitutive Material Model for Energy Absorption in Impact Applications

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1537
Author(s):  
Luděk Hynčík ◽  
Petra Kochová ◽  
Jan Špička ◽  
Tomasz Bońkowski ◽  
Robert Cimrman ◽  
...  
Keyword(s):  
Strain Rate ◽  
Material Model ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Linear Low Density Polyethylene ◽  
Stress Strain ◽  
Rate Dependent ◽  
Constitutive Material Model ◽  
Principal Directions ◽  
Constitutive Material

Current industrial trends bring new challenges in energy absorbing systems. Polymer materials as the traditional packaging materials seem to be promising due to their low weight, structure, and production price. Based on the review, the linear low-density polyethylene (LLDPE) material was identified as the most promising material for absorbing impact energy. The current paper addresses the identification of the material parameters and the development of a constitutive material model to be used in future designs by virtual prototyping. The paper deals with the experimental measurement of the stress-strain relations of linear low-density polyethylene under static and dynamic loading. The quasi-static measurement was realized in two perpendicular principal directions and was supplemented by a test measurement in the 45° direction, i.e., exactly between the principal directions. The quasi-static stress-strain curves were analyzed as an initial step for dynamic strain rate-dependent material behavior. The dynamic response was tested in a drop tower using a spherical impactor hitting a flat material multi-layered specimen at two different energy levels. The strain rate-dependent material model was identified by optimizing the static material response obtained in the dynamic experiments. The material model was validated by the virtual reconstruction of the experiments and by comparing the numerical results to the experimental ones.

Physical and mechanical properties of linear low-density polyethylene/cycloolefin copolymer/layered silicate nanocomposite

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 ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Layered Silicate ◽  
Physical And Mechanical Properties ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Linear Low Density Polyethylene

Shear characterization of CaCO3-filled linear low density polyethylene

1988 ◽  
Vol 27 (2) ◽  
pp. 172-178 ◽  
Author(s):  
S. Ottani ◽  
A. Valenza ◽  
F. P. La Mantia
Keyword(s):  
Low Density Polyethylene ◽  
Low Density ◽  
Linear Low Density Polyethylene
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