DOI: 10.4121/4bdee833-cf57-41ad-bd4a-570a77b27f65.v1
title: Dataset underlying the publication: Going from Inner-Skinned to Outer-Skinned Polyelectrolyte Multilayer Based Hollow Fiber Nanofiltration Membranes

description: The data is always named after the support membrane that was analyzed. The conditions under which the supports were fabricated including their name can be found in the file "Hollow_Fibre_spinning_conditions_with_Sample_names.csv" included in this folder. In some cases the supports were also coated with polyallylamine hydrochloride (PAH) and sodium polystyrene sulfonate (PSS) or Rhodamine labeled PAH (PAHRho; for the fluorescence spectroscopy samples). In this case the name of the support is followed by the distinction "coated". The type of coating used is specified in either the file or folder name containing the images.<br>Filtration: Contains experimental results of pure water permeability, MgSO4 retention data and 90% molecular weight cut off (MWCO) data based on gel permeation chromatography data (See GPC_data). Measured quantities are: active fiber length (m), average [inlet and outlet] pressure (bar), permeate mass (g) [filled beaker-empty beaker], permeation time (s), hollow fibre outer diameter (mm), feed and permeate conductivity (microS/cm).<br>SEM: SEM images of the different hollow fibres spun. The images are each saved in folders named after the sample that is seen in the image. The conditions under which each sample were fabricated are stated in the article and in the file " Hollow_Fibre_spinning_conditions_with_Sample_names.csv". The magnification at which the images were taken can be seen in the footer of the images. The images within the folders have the following naming convention: 'x_x_type_location#y'<br>Here,- x_x are sample identifiers- type is either "cross" or "surface" indicating a cross-sectional image or top view image respectively.- location is the part of the membrane that has been imaged. This can be "bore", "centre" or "shell", where bore is the inside of the hollow fibre wall, centre the middle of the fibre wall on the cross-sectional images, and shell the outside of the hollow fibre. The "location" is sometimes missing in the filename. This indicates that the entire cross-section of the fibre was imaged.- y is an image identifier when multiple images are taken of a similar location of the same sample<br>GPC_data: This includes the raw GPC data used for determining the MWCO. The data displays signal intensity v.s. molecular weight (g/mol) for the feed solution and permeate solutions of the tested membranes. The solutions contained either polyethylene glycol (PEG) (100-10000 g/mol) for the membranes coated with PAH/PSS or dextrans (18.1-200.000 g/mol) for the uncoated supports.<br>Matlab_scripts: Contains the code used for calculating the pressure drop inside the membrane, loss in transmembrane pressure and increase in membrane surface area compared to commercial geometries as a function of membrane geometry and operational conditions. The explanation of the code is added in comments behind each line of code. The code is provided both in a .m file and a .txt file format and was written using Matlab 2021b.<br>Output_data_model: This folder contains the output data of the model that was plotted in the article that this dataset belongs to. The three files contain: 1) pressure drop data (bar) v.s. bore radius (m) of a fibre. 2) Pressure data (bar) v.s. the location within the fibre bore along the length of the membrane (m). 3)Active membrane surface area increase (as compared to commercial fibres; unitless) v.s. transmembrane pressure loss (TMP_loss; %). All three of these datasets include data for membranes with 5 different ratios between the bore radius and wall thickness of the fibre. All datasets were generated with the input conditions mentioned in the main article.<br>Fluorescence_spectroscopy: This file contains the raw czi data files containing the 40 images made at different focus depths to generate a 3D image. These files can be opened in the freeware software FIJI with which they were converted to 2D overlays. In the 2D overlays the maximum intensity value of the 40 images was saved for each pixel and transposed into a 2D image. These 2D images were saved as PNG files and are also included in the folder.<br>