2022

Publications in refereed journals:

• Progress on Polymers Containing Imide Rings for Advanced Technologies: A Contribution from ICMPP of the Romanian Academy

 M. D. Damaceanu

 Chemistry 2022, 4, 1339-1359. https://doi.org/10.3390/chemistry4040088

Results dissemination in national/international conferences:

• Gas separation membranes obtained from hexafluoroisopropylidene-containing polyimide blends

M. D. Damaceanu, I. Butnaru, C. P. Constantin, A. Wolińska-Grabczyk,

6th International Conference on Chemical Engineering, Innovative Materials and Processes for a Sustainable Development, ICCE-2022, Iasi-Romania, October 5-7, 2022, Program: S1-P33, p.23.     

• Preparation and characterization of polyimide blend membranes for energy-efficient CO₂ separation

M. D. Damaceanu, I. Butnaru, C. P. Constantin, A. Wolińska-Grabczyk

The 13th International Conference Innovative Technologies for Joining Advanced Materials, Timisoara-Romania, November 24-25, 2022, Program: p. 7.

A sumary of the main results obtained during project implementation in 2022 can be found below:

Stage I (year 2022) of memPIM-PIs project aimed at developing a technology for preparation of polymer membranes for CO₂ separation/capture based on polyimides containing voluminous DOPO units and mixtures of polyimides based on them. For this purpose, an aromatic diamine-type monomer containing DOPO group grafted on a triazine ring was synthesized. Based on it, three polyimides with DOPO units and different chain flexibilities modulated by the variable structure of the diimide segment were prepared. Polymer synthesis reactions were accomplished by direct polycondensation, in a single step, at high temperature, in a polar aprotic solvent. The polymers with DOPO units were structurally characterized by spectral methods (FTIR, ¹H and ³¹P-NMR), which confirmed their correct structure. Upon excitation with UV light, the synthesized polyimides with DOPO units exhibited weak fluorescence in the blue-green spectral range, due to the presence of the charge transfer complex developed between the diamine segment as an electron donor and the diimide segment as an electron acceptor. All polymers showed good solubility in polar aprotic solvents such as DMF, NMP, DMAc, which allowed their processing from solution in form of films. Although an extensive work was carried out to optimize the processing conditions of these polymers in form of self-standing membranes, only brittle films were obtained, which cannot be detached from the support. Therefore, the DOPO-containing polyimides were mixed with a polyimide based on 6FDA with very good film-forming properties, whose synthesis was carried out starting from commercial monomers. Thus, 7 polymer blends were prepared in different mass ratios, which were processed in form of membranes with good mechanical integrity. In order to obtain uniform membranes, the application of a controlled thermal regime to the blend solutions was applied after establishing the optimal processing conditions and the optimal ratios between the two components of the blend. The resulting self-standing membranes were characterized from the morphological and miscibility point of view, the experimental results demonstrating their uniformity and the homogeneous mixing at the molecular level of the two polymeric components. In the next stage of the project, these membranes will be characterized from the physico-chemical point of view and explored with regard to the gas permeation capacity, with an emphasis on the separation/capture of CO₂. Part of the outcome results of this project stage were disseminated in the form of 2 oral communications at international scientific events and a review paper, which was published in the ISI journal "Chemistry".