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Preparation and Compatibility Evaluation of Polypropylene/High Density Polyethylene Polyblends.
Jia-Horng Lin1,2,3, Yi-Jun Pan4, Chi-Fan Liu5
1Laboratory of Fiber Application and Manufacturing, Department of Fiber and Composite Materials, Feng Chia University, Taichung City 40724, Taiwan. jhlin@fcu.edu.tw.
Materials (Basel, Switzerland)
|August 11, 2017
Summary
This study blended polypropylene (PP) and high-density polyethylene (HDPE), finding they are incompatible but HDPE improves PP
Area of Science:
- Polymer Science
- Materials Science
Background:
- Polypropylene (PP) and high-density polyethylene (HDPE) are common thermoplastics.
- Understanding their blend properties is crucial for material development.
Purpose of the Study:
- To investigate the properties and compatibility of melt-blended PP/HDPE polyblends.
- To determine the effect of HDPE content on PP/HDPE blend characteristics.
Main Methods:
- Melt-blending of PP and HDPE with similar melt flow index (MFI).
- Characterization using tensile, flexural, and Izod impact tests.
- Microscopy (SEM, PLM), spectroscopy (FTIR), thermal analysis (DSC), and X-ray diffraction (XRD).
Main Results:
- SEM confirmed PP and HDPE are incompatible, with PP as the continuous phase and HDPE as the dispersed phase.
- FTIR indicated a physical blend without chemical structure alteration.
- DSC and XRD showed no correlation between HDPE and PP's crystalline structure or stability.
- PLM revealed spherulite stacking and incompatibility, leading to incomplete morphology and smaller PP spherulites.
- Mechanical testing demonstrated improved impact strength of PP with HDPE addition.
Conclusions:
- PP and HDPE are immiscible polymers, forming a physically blended system.
- HDPE addition negatively impacts PP's crystalline structure and morphology.
- Despite incompatibility, HDPE enhances the impact strength of polypropylene.
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