Polymers as Reference Partitioning Phase: Polymer Calibration for an Analytically Operational Approach To Quantify...

Area of Science:

• Environmental Chemistry
• Polymer Science
• Analytical Chemistry

Background:

• Polymers are widely used for enriching hydrophobic organic chemicals (HOCs) in analytical techniques.
• Understanding partitioning behavior of HOCs between different phases is crucial for accurate environmental measurements.

Purpose of the Study:

• To introduce polymer-polymer partitioning as a method for analyzing HOCs.
• To establish polymers as a reference partitioning phase for calibrating analytical methods and calculating partition coefficients.
• To investigate partitioning differences of HOCs between various polymers.

Main Methods:

• Determined polymer-polymer partition coefficients for polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and organochlorine pesticides (OCPs).
• Equilibrated 13 silicones, including polydimethylsiloxane (PDMS) and low-density polyethylene (LDPE), in methanol-water solutions.
• Calculated new polymer-based and multimedia partition coefficients using polymer-polymer partition coefficients as conversion factors.

Main Results:

• Polymer-polymer partition coefficients near unity indicated similar absorption capacities for some PDMS materials.
• Larger deviations from unity were observed within silicones and between silicones and LDPE.
• Identified uncertainty in polymer volume as a source of error in partition coefficient determination.
• Minor cosolvent effects were noted on determined polymer-polymer partition coefficients.

Conclusions:

• Polymer-polymer partitioning provides deeper insight into HOC partitioning behavior.
• Polymers can serve as a linking third phase for quantitative understanding of HOC equilibrium partitioning.
• This approach enhances consistency checking and calculation of partition coefficients for environmental contaminants.