Biobased Polycarbonate as a Gas Separation Membrane and “Breathing Glass” for Energy Saving Applications

Abstract

of biobased diols with phosgene derivatives [2,4] and the catalytic copolymerization of sustainable epoxides and CO 2 . [5,6] The copolymerization of biobased epoxides and CO 2 is of particular interest as it combines the use of biobased raw materials and the reduction of CO 2 . The anthropogenic emission of CO 2 accumulates to 32 Gt each year, which is caused mainly by the incineration of carbon matter. CO 2 is a greenhouse gas that contributes significantly to the warming of the earth's atmosphere. [7] Global warming increases chances of catastrophic weather phenomena and a rising sea level and, thus, impacts on our everyday life dramatically. Measures have been taken to reduce the emission and to contain the rise of CO 2 levels in the atmosphere in the last few decades. Part of these measures can be described by the concepts of carbon capture and storage/utilization (CCS/CCU). [8][9][10] The CCU deals with the separation and transformation of CO 2 from process gases (e.g., combustion gases in power plants and natural gas) to prevent emission of the greenhouse gas into the atmosphere. The separation step is achieved by the use of either chemical/physical absorbents or organic/inorganic membrane materials. [9,11] The class of absorbents is dominated nowadays by alkanol amine solutions, for example, monoethanolamine and diethanolamine, which require high temperatures for regeneration of the solvent. [12,13] Hence, these "wet-scrubbing" processes are connected to a considerable energy penalty that adds to the total emission of CO 2 . [14] The more energy-efficient-though less developed-technology relies on the use of membrane materials that separate CO 2 from other process gases by size exclusion (mostly hybrid metal-organic frameworks) [15,16] or solubility/diffusivity mechanisms (polymeric membranes), respectively. [17,18] The latter comprise a group of polymeric materials that exhibit permeabilities P (rate of transport through the matrix) and selectivities α (preference of one gas over the other; in this article the "ideal selectivity" is calculated as the ratio of two permeabilities) extending over several orders of magnitude. [19] However, those materials suffer frequently from low long-term stability, known as aging, which has prevented industrial application so far. [20] The large volumes of CO 2 captured in the industrial processes are either stored in gas-tight (often natural) basins (CCS) [10] or transformed into high-value chemicals via various chemical routes (CCU). Some of those routes are The biobased poly(limonene carbonate) (PLimC) synthesized by catalytic copolymerization of trans-limonene oxide and CO 2 unifies sustainability, carbon capture and utilization of CO 2 in one material. Films of PLimC show surprisingly high gas permeation and good selectivity. Additionally, it is not only very permeable to gases, but also to light, while simultaneously being a good heat insulator and mechanically strong, representing a novel type of material that is defined here as "breathing glass." Hence, this stud...

CO2-fixation into cyclic and polymeric carbonates: principles and applications

“…255,455 In contrast, poly(limonene carbonate) possesses very high gas permeability, which, combined with its relatively good mechanical properties, transparency and thermal insulation properties, renders it potentially suitable for application as "breathing glass" in energy-efficient buildings or in greenhouses, providing passive ventilation through these windows and thereby eliminating the need for additional ventilation systems. 456…”

Functional Polycarbonates from Carbon Dioxide and Tailored Epoxide Monomers: Degradable Materials and Their Application Potential

“…This material shows high gas permeability and transparency, combined with good heat insulation and mechanical strength. Due to these properties, the authors introduced the descriptive term “breathing glass.” In Figure relative values of the key characteristics of PLimC are plotted in a radar chart to compare PLimC with established transparent materials, such as aromatic polycarbonates (BPA‐PC), polymethylmethacrylate (PMMA), and soda‐lime glass. The relative scale is between 0 (worst performance, center of the chart) and 10 (best performance).…”

“…Relative material properties of PLimC compared to the aromatic polycarbonate BPA‐PC, PMMA, and soda‐lime glass on a scale between 0 (worst performance, center of the chart) and 10 (best performance). Reproduced with permission . Copyright 2017, John Wiley & Sons, Inc.…”

Polymers of Limonene Oxide and Carbon Dioxide: Polycarbonates of the Solar Economy

“…These biobased polymers hold great potential for practical utilization, given both their excellent sustainability profile (with complete back-to-monomer recyclability) [18] and a vast scope of potential applications which include protecting coatings, [19] breathing-glass windows, [10] and the addition of permanent antibacterial activity and hydrophilization. [11] Prior to that, however, the main hurdle to their large-scale commercialization needs to be overcome: the limited supply of limonene.…”

“…[9] Shortly afterwards, the team led by Greiner discovered that PLC has excellent gas permeability to molecules such as CO2 and O2 making the biobased polycarbonate suitable to manufacture gas separation membranes and new generation windows for energyefficient buildings (the polymer is also a good heat insulator). [10] Finally, in an intriguing work in which new antibacterial, mechanical, thermal, self-healing and protective coating properties were demonstrated, [11] the same team showed how simple chemical derivatisation of the pendant isoprene double bond of limonene moieties in each repeating unit of the polymer, allows the use of PLC as true polymeric platform system ("synthetic toolbox") from which several new properties may arise.…”