Related Experiment Video
Updated: Nov 10, 2025
07:28
Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization
Published on: November 27, 2015
13.5K
Phase Equilibria and Interdiffusion in Bimodal High-Density Polyethylene (HDPE) and Linear Low-Density Polyethylene
Ildar I Salakhov1, Anatoly E Chalykh2, Nadim M Shaidullin1
1PJSC NIZHNEKAMSKNEFTEKHIM, Nizhnekamsk, Sobolekovskaya 23, 423574 Republic of Tatarstan, Russia.
Polymers
|April 3, 2021
Summary
High-density polyethylene (HDPE) and low-density polyethylene (LLDPE) blends exhibit unrestricted mixing in solid crystal solutions. Their thermodynamic compatibility and interdiffusion kinetics were analyzed across various temperatures and compositions.
Area of Science:
- Polymer Science
- Materials Science
- Physical Chemistry
Background:
- Polyethylene blends are crucial in various industries.
- Understanding phase behavior and interdiffusion is key for material properties.
- High-density polyethylene (HDPE) and linear low-density polyethylene (LLDPE) are widely used polymers.
Purpose of the Study:
- To investigate the phase equilibrium and thermodynamic parameters of HDPE-LLDPE blends.
- To construct phase state diagrams for HDPE-LLDPE systems.
- To analyze the kinetics and morphology of interphase boundaries during crystallization.
Main Methods:
- Refractometry
- Differential scanning calorimetry (DSC)
- Optical laser interferometry
- X-ray phase analysis
- Optical polarization microscopy
Main Results:
- HDPE-LLDPE systems form solid crystal solutions with unrestricted mixing.
- Thermodynamic compatibility was observed in melt and crystallization regions.
- Interdiffusion coefficients and spherulite sizes were determined.
- Kinetics of interphase boundary formation during crystallization were analyzed.
Conclusions:
- The study confirms thermodynamic compatibility between HDPE and LLDPE components.
- Phase diagrams indicate unrestricted mixing, suggesting good blendability.
- Analysis provides insights into crystallization behavior and morphology development in polyethylene blends.
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