Mixed substituent ether‐containing polyphosphazene/poly(bis‐phenoxyphosphazene) blends as membranes for CO₂ separation from N₂

Abstract

Polyphosphazenes gain much of their physical and chemical properties from the substituents attached to the phosphorus atoms in the backbone. Poly(phosphazenes) that have short‐chain polyether containing substituents, such as, 2‐(2‐methoxyethoxy)ethanol, have high CO2 permeability and selectivity over N2 as well as resistance to degradation under humidification at 60°C. However, the principal shortcomings of this polymer are the poor mechanical and surface characteristics. Blending of an example of this polyphosphazene (MEEP‐80) with poly(bis‐phenoxyphosphazene) (PPOP) has yielded more durable materials that have a non‐adhesive surface. In this work, the blended polymer membranes were found to have increased CO2 permeability with higher selectivity over N2. Thermal analysis and the application of transport models support a structure of the blends that is not either an intimate blend or phase separated bulk structure, but one where PPOP domains retain their crystallinity and are dispersed within an amorphous MEEP‐80 phase.

Creation of Polymer Datasets with Targeted Backbones for Screening of High-Performance Membranes for Gas Separation

“…In this study, we utilized seven polymer backbone structures, as recommended by our experimental colleagues, and these structures are illustrated in Figure . Polymer backbones that have demonstrated good performance in producing rubbery polymer membranes for gas separation applications were targeted. − Rubbery polymers deliver stable and durable gas separation performance compared to their counterparts– glassy polymers that usually experience physical aging.…”

Creation of Polymer Datasets with Targeted Backbones for Screening of Gas Permeability and Selectivity

“…All the backbones examined in this study have demonstrated good performance in producing polymer membranes. [46][47][48][49][50][51][52]…”

Life Cycle Assessment of Innovative Carbon Dioxide Selective Membranes from Low Carbon Emission Sources: A Comparative Study

“…Our research group has developed membranes that can enrich CO 2 concentration from low carbon emitting sources using the concept of low-concentration CO 2 enrichment [47]. Over the course of last three decades, several unique polyphosphazenes have been developed for a variety of applications [43][44][45][46][48][49][50][51][52][53][54][55][56][57][58]. Among these polyphosphazenes, poly[bis((2-methoxyethoxy)ethoxy) phosphazene (MEEP, Figure 1) is a specialty polymer that can fabricate thin, self-healing CO 2 /N 2 selective membranes [59].…”