Linear Low Density Polyethylene-Thermotropic Liquid Crystal Composite Substrate for High-Frequency Devices: Dielectric Characterization

2021 ◽  
Author(s):  
Pulin Dutta ◽  
Bhaben Saikia ◽  
Parameswara Rao Alapati ◽  
Kunal Borah
Keyword(s):  
Liquid Crystal ◽  
High Frequency ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Linear Low Density Polyethylene ◽  
Dielectric Characterization ◽  
Thermotropic Liquid Crystal ◽  
Composite Substrate ◽  
High Frequency Devices ◽  
Crystal Composite

scholarly journals Design and Synthesis of Polysiloxane Based Side Chain Liquid Crystal Polymer for Improving the Processability and Toughness of Magnesium Hydrate/Linear Low-Density Polyethylene Composites

Polymers ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 911
Author(s):  
Xiaoxiao Guan ◽  
Bo Cao ◽  
Jianan Cai ◽  
Zhenxing Ye ◽  
Xiang Lu ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Shear Rate ◽  
Decomposition Temperature ◽  
Liquid Crystal Polymer ◽  
Low Density Polyethylene ◽  
Processing Temperature ◽  
Low Density ◽  
Linear Low Density Polyethylene ◽  
Design And Synthesis ◽  
Crystal Polymer

In this study, a polysiloxane grafted by thermotropic liquid crystal polymer (PSCTLCP) is designed and synthesized to effectively improve the processability and toughness of magnesium hydroxide (MH)/linear low-density polyethylene (LLDPE) composites. The obtained PSCTLCP is a nematic liquid crystal polymer; the liquid crystal phase exists in a temperature range of 170 to 275 °C, and its initial thermal decomposition temperature is as high as 279.6 °C, which matches the processing temperature of MH/LLDPE composites. With the increase of PSCTLCP loading, the balance melt torque of MH/LLDPE/PSCTLCP composites is gradually decreased by 42% at 5 wt % PSCTLCP loading. Moreover, the power law index of MH/LLDPE/PSCTLCP composite melt is smaller than 1, but gradually increased with PSCTLCP, the flowing activation energy of PSCTLCP-1.0 is lower than that of MH/LLDPE at the same shear rate, indicating that the sensitivity of apparent melt viscosity of the composites to shear rate and to temperature is decreased with the increase of PSCTLCP, and the processing window is broadened by the addition of PSCTLCP. Besides, the elongation at break of MH/LLDPE/PSCTLCP composites increases from 6.85% of the baseline MH/LLDPE to 17.66% at 3 wt % PSCTLCP loading. All the results indicate that PSCTLCP can significantly improve the processability and toughness of MH/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
Sign in / Sign up

Export Citation Format

Share Document