Elucidating Structural Variations at Heterogeneous Interfaces in Polymer Blends Using Evolved Gas Analysis with...

Area of Science:

• Polymer Science
• Analytical Chemistry
• Materials Science

Background:

• Analyzing molecular-scale structural variations at heterogeneous interfaces in polymer blends is crucial for understanding material properties.
• Complex mass spectra from pyrolysis products of polymer blends pose significant interpretation challenges.

Purpose of the Study:

• To develop and validate a novel analytical method for characterizing polymer blend interfaces.
• To investigate the role of maleic anhydride-grafted styrene-ethylene butylene-styrene triblock copolymer (MASEBS) as a compatibilizer in polypropylene (PP)/polyamide 6 (PA6) blends.

Main Methods:

• Evolved gas analysis with time-of-flight mass spectrometry (EGA-TOFMS) using field ionization for temperature-dependent pyrolysis product analysis.
• Filtered Kendric Mass Defect (filtered KMD) technique to isolate signals of individual polymer components.
• Elected ion current curves derived from filtered KMD to analyze component-specific pyrolysis behavior.

Main Results:

• The developed analytical framework successfully characterized the ternary polymer blend (PP/PA6/MASEBS).
• MASEBS was identified to chemically interact with PA6, acting as an effective compatibilizer.
• Optimal interfacial compatibility and mechanical properties were observed with 1 wt% MASEBS, while higher concentrations led to performance reduction due to excess MASEBS.

Conclusions:

• The combination of EGA-TOFMS and filtered KMD provides a powerful tool for analyzing complex polymer blend interfaces.
• Understanding the structure-property relationships in polymer blends is enhanced by this analytical approach.
• The study demonstrates the critical role of MASEBS concentration in compatibilizing PP/PA6 blends.