This readme.txt file was generated on August 2, 2024 by Jennifer E. Laaser Supporting Data for: Segregative Phase Separation of Strong Polyelectrolyte Complexes at High Salt and High Polymer Concentrations -------------------------------------------------------------- Data in this dataset was generated/prepared by: Principal Investigator: Jennifer E. Laaser Assistant Professor University of Pittsburgh Department of Chemistry 219 Parkman Ave Pittsburgh, PA 15260 j.laaser@pitt.edu Research Team: Conner H. Chee Graduate Student University of Pittsburgh Rotem Benharush Undergraduate Student University of Pittsburgh Lexi R. Knight Undergraduate Student University of Pittsburgh Data was collected between January 2020 and January 2024 at the University of Pittsburgh (Pittsburgh, PA). -------------------------------------------------------------- Use of this dataset is governed by the policies of the D-Scholarship@Pitt repository. Unless otherwise specified in the dataset or contradicted by D-Scholarship@Pitt policies, this dataset is licensed under the Creative Commons Attribution 4.0 International. To view a copy of this license, visit https://creativecommons.org/licenses/by/4.0/ Recommended citation: Chee, C. H.; Benharush, R.; Knight, L. R.; Laaser, J. E.; (2024). Supporting Data for: Segregative Phase Separation of Strong Polyelectrolyte Complexes at High Salt and High Polymer Concentrations. Retrieved from D-Scholarship@Pitt, __URL__, __DATE__. For uses of this dataset that do not fall under the above license, contact the Principal Investigator named above for usage permissions. -------------------------------------------------------------- Overview/organization of dataset: This dataset consists of all data included in the following manuscript: Segregative Phase Separation of Strong Polyelectrolyte Complexes at High Salt and High Polymer Concentrations prepared by authors Conner H. Chee, Rotem Benharush, Lexi R. Knight, and Jennifer E. Laaser, and submitted for publication in August, 2024. The dataset consists of four types of data: 1) Photographs of samples; 2) Thermogravimetric analysis (TGA) of samples; 3) Fourier-transform infrared (FTIR) spectra of samples; and 4) Nuclear magnetic resonance (NMR) spectra of samples. Files are organized into folders/zip files by data type. Photographs are provided as .jpg files; TGA, FTIR, and NMR data are provided as .csv or .txt files, and NMR data are also provided in the native Bruker file format output by the instrument used for data acquisition. The file "UPW-paper-fileguide-CCJL.xlsx" contains a detailed key mapping file names to specific sample compositions reported in the manuscript. Note that in this file, for phase-separated samples, phase "U" refers to the upper/less dense phase of the sample, while phase "L" refers to the lower/more dense phase of the sample. Details regarding the sample preparation, instruments, and methods used for all reported experiments are included in the methods section, below. -------------------------------------------------------------- Experimental Methods (copied from the manuscript): Materials Poly(sodium 4-styrene sulfonate) (PSSNa, Mw = 200,000 g · mol-1, 20 wt%) solution and poly(diallyldimethylammonium chloride) (PDADMAC, Mw = 200,000-350,000 g · mol-1, 23 wt%) solution were purchased from Sigma Aldrich. Potassium bromide (KBr) was purchased from Fisher Scientific. All samples were prepared using Milli-Q water obtained from a Synergy UV water purification system purchased from Millipore Sigma. All materials, except for PSSNa and PDADMAC, were used as received. PSSNa and PDADMAC were dialyzed before use using standard RC dialysis tubing with a molecular weight cutoff of 6-8 kg · mol-1 (Spectra/Por, 08-670D). Sample Preparation Samples were prepared by direct mixing of dried PEC, salt, and water. Briefly, a bulk PEC was first prepared by dissolving stoichiometric amounts of PSSNa and PDADMAC in a 2.5 M KBr solution. Milli-Q water was then added slowly until the KBr concentration was below 0.1 M, resulting in precipitation of the PSS/PDADMA complex. The supernatant was decanted, replaced with milliQ water, and the PEC was allowed to sit for 24 hours to wash out excess salt. This process was repeated a total of three times. The bulk PEC was then dried using a lyophilizer and ground with a mortar and pestle, yielding a white powder. NMR revealed that this parent PEC was stoichiometrically balanced, containing 50.7% PSS and 49.3% PDADMA repeat units. Samples with targeted PEC and salt concentrations were then prepared by combining the requisite amounts of dry PEC, KBr, and water in an Eppendorf tube. To ensure complete mixing, the samples were vortexed for 1 minute at 2000 rpm after each addition. Samples were then centrifuged for 1 hour at 4000 rpm, left to equilibrate for 2 days, centrifuged again for 1 hour, and left to equilibrate for at least 1 week before characterization. Thermogravimetric Analysis Thermogravimetric analysis (TGA) measurements were carried out on a Q5000 IR Thermogravimetric Analyzer (TA Instruments) using a protocol adapted from Li et al.(Macromolecules, 2020, 54, 105–114) For each measurement, approximately 15 mg of sample was loaded onto a platinum pan. The sample was held at 25◦C for 5 minutes, and was then heated to 100◦C at 20◦C · min-1 and held at this temperature for 1 hour to drive off water. The temperature was then ramped to 600 ◦C at a rate of 10 ◦C · min-1 and the sample was held at 600 ◦C for an additional 1 hour to ensure complete removal of organic components of the sample. The temperature was then finally ramped to 680 ◦C at 10 ◦C · min -1 to complete the measurement. All measurements were carried under air to facilitate the complete removal of the organic components. Measurements on standard solutions with known compositions indicated that this protocol yielded compositions accurate to within 1 wt%. Infrared Spectroscopy Attenuated Total Reflection-Fourier Transform Infrared Spectroscopy (ATR-FTIR) measurements were carried out on a Spectrum Two (Perkin Elmer) instrument. Measurements were acquired at a resolution of 1 cm-1 with a sampling interval of 0.25 cm-1 and were averaged over 16 scans. For the polymer rich phases, the sample was compressed with the instrument’s pressure gauge until the pressure read 100 Pa to ensure sufficient contact between the polymer sample and the ATR crystal. Nuclear Magnetic Resonance 1H-NMR (Avance 400 MHz, Bruker) spectra were used to determine the polymer stoichiometry in each sample. The polymer rich and polymer poor phases of the phase-separated samples were separated and dried with a lyophilizer. The dried samples, which consisted of polymer and salt, were ground with a mortar and pestle, and were then dissolved in a 2.5 M KBr solution in D2O, targeting a polymer concentration of 15 mg·ml-1. NMR measurements were finally carried out using a relaxation delay (d1 time) of 10 seconds to ensure accurate integrations. -------------------------------------------------------------- Funding: This work was supported by a grant from the National Science Foundation (CHE-2203857). -------------------------------------------------------------- Questions regarding this dataset should be addressed to the study PI, Jennifer Laaser, at j.laaser@pitt.edu