Molecular Disaggregation Process of PTFE Using Sodium Chloride: A Study by Infrared Spectroscopy

Area of Science:

• Materials Science
• Polymer Chemistry
• Analytical Chemistry

Background:

• Mechanical recycling of polytetrafluoroethylene (PTFE) is essential but challenging due to strong molecular aggregation.
• Traditional methods rely on fluorocarbon solvents, raising environmental concerns.
• Developing solvent-free recycling techniques is a priority in fluorocarbon chemistry.

Purpose of the Study:

• To investigate the molecular disaggregation process of PTFE using sodium chloride and planetary ball milling.
• To detail the effectiveness of this novel solvent-free technique.
• To utilize infrared (IR) spectroscopy for analyzing PTFE's hierarchical structures during disaggregation.

Main Methods:

• Planetary ball milling of PTFE with solid sodium chloride.
• Solvent-free mechanical treatment of PTFE.
• Infrared (IR) spectroscopy for molecular analysis and structural characterization.

Main Results:

• Sodium chloride-assisted ball milling significantly reduces PTFE crystallinity.
• IR spectroscopy confirms PTFE particle fragmentation and molecular disaggregation.
• Helical defects in perfluoroalkyl chains are observed, correlating with molecular disaggregation.

Conclusions:

• Solid sodium chloride with ball milling is an effective solvent-free method for PTFE disaggregation.
• IR spectroscopy provides detailed insights into PTFE's molecular and structural changes during recycling.
• This technique offers a promising environmentally friendly approach to PTFE recycling.