UV-cross linking,  CO2 adsorb
224917630
UV irradiation assisted cross linking of high molecular weight poly (ethylene oxide) with poly (ethylene glycol) diacrylate to prepare CO2 selective membranes
Abstract In this work, the high molecular weight poly (ethylene oxide) (PEO) was cross linked under UV irradiation to decrease its crystallinity in order to prepare a high performance CO2 selective membrane. Poly (ethylene glycol) diacrylate (PEGDA) containing CO2 philic ether oxygen group was used as both photo initiator and cross linking agent. It was found that the crystallinity degree from 82.4% for the neat PEO membrane decreased to 65.4% for the cross linked PEO membrane by the proposed cross linking technique. The observations indicated that the structural and gas separation properties of the cross linked PEO membranes strongly depend on the PEGDA concentration and UV irradiation time. When the PEGDA concentration was between 3 and 7 %wt and at UV irradiation time of 30 min, the prepared membrane overcame Robeson upper bound and indicated a fairly good separation performance in the case of CO2 separation from N2, compared to the similar cross linked PEG based membranes in the literature.
Fereshteh Motahari Ahmadreza Raisi
216169214
UV Cross Linked Poly(ethylene glycol) Based Membranes with Different Fractional Free Volumes for CO2 Capture: Synthesis, Characterization, and Thiol ene Modification Evaluation
CO2 separation is of paramount importance in CO2 capture from flue gas and natural gas sweetening. In this paper, the thiol ene UV photopolymerization technique was employed to synthesize improved
Somayeh Norouzbahari Reza Gharibi
213192360
Influence of Anion Structure on Thermal, Mechanical and CO2 Solubility Properties of UV Cross Linked Poly(ethylene glycol) Diacrylate Iongels
Iongel based CO2 separation membranes were prepared by fast 1 min) UV initiated polymerization of poly(ethylene glycol) diacrylate (PEGDA) in the presence of different ionic liquids (ILs) with the [C2mim] cation and anions such as [TFSI] [FSI] [C(CN)3] and [B(CN)4] The four ILs were completely miscible with the non ionic PEGDA network. Transparent and free standing iongels containing between 60 and 90 %wt of IL were obtained and characterized by diverse techniques (FTIR, TGA, DSC, DMTA, SEM, CO2 solubility and pure gas permeability) The thermal and mechanical stability of the iongels, as well as CO2 solubility, were found to be strictly dependent on the IL content and the anion's nature. The TGA results indicated that the iongels mostly follow the thermal profile of the respective neat ILs. The DMTA analysis revealed that the iongels based on fluorinated anions have higher storage modulus than those of cyano functionalized anions. Conversely, the PEGDA C(CN)3 iongels presented the highest CO2 solubility values ranging from 72 to 80 mmol/g. Single CO2 permeabilities of 583 29 Barrer and ideal CO2/N2 selectivities of 66 3 were obtained with the PEGDA 70 C(CN)3 iongel membrane. This work demonstrates that the combination of PEGDA with high contents of the best performing ILs is a promising and simple strategy, opening up new possibilities in the design of high performance iongel membranes for CO2 separation.
Membranes
Ana P S Martins Asier Fdz De Anastro Jorge L Olmedo-Martinez Ana R Nabais Luisa A Neves David Mecerreyes Liliana C Tome
225296467
Multi responsive poly(amidoamine) initiated dendritic star supramolecular structures containing UV cross linkable coumarin groups for smart drug delivery
Abstract Dendritic star supramolecular structure of poly(amidoamine) g [polystyrene b (2 (dimethylamino)ethyl methacrylate co 11 (4 methyl 2 oxo 2H chromen 7 yl)oxy)undecyl acrylate) (PAMAM g P(St b (DMAEMA co CuA) was synthesized via grafting from atom transfer radical polymerization (ATRP) by using PAMAM initiator as smart drug carrier. This structure consisted of multi responsive unites of hydrophilic PDMAEMA regarding to pH change, temperature, and CO2 gas and the coumarin molecule as photocrosslinking agent. Photocrosslinking agent is efficient for controlling DOX release after dimerization under UV light. The chemical structure of samples was confirmed by proton nuclear magnetic resonance (1H NMR) and their molecular weight was studied by gel permeation chromatography (GPC) The change of hydrophilic length of PDMAEMA and pH media resulted in various morphologies including hollow sphere, snowman and dumbbell like particles. The morphology of supramolecular assemblies was not changed after photocrosslinking, which confirmed the structure stabilization under UV light irradiation of 365 nm. Fluorescence microscopy was confirmed the presence of fluoresce segments in self assembled supramolecular structures. Dynamic light scattering (DLS) indicated that the size of supramolecular assemblies was changed through the response to external stimuli such as pH, temperature, and CO2 gas. The DOX release behavior was investigated in different conditions such as pH, temperature, and after photocrosslinking under UV light of 365 nm.
Bahareh Razavi Robab Abbaszadeh Mehdi Salami-Kalajahi Hossein Roghani-Mamaqani
103816760
Gas permeation properties of a metallic ion cross linked PIM 1 thin film composite membrane supported on a UV cross linked porous substrate
Abstract Metallic ion cross linked polymer of intrinsic microporosity (PIM 1) thin film composite (TFC) membranes supported on an ultraviolet (UV) cross linked porous substrate were fabricated. The UV cross linked porous substrate was prepared via polymerization induced phase separation. The PIM 1 TFC membranes were fabricated via a dip coating procedure. Metallic ion cross linked PIM 1 TFC membranes were fabricated by hydrolyzing the PIM 1 TFC membrane in an alkali solution and then cross linking it in a multivalent metallic ion solution. The pore size and porous structures were evaluated by low temperature N2 adsorption desorption analysis. The membrane structure was investigated by field emission scanning electron microscopy. The effects of heat treatment and pore forming additives on the gas permeance of the UV cross linked porous substrate are reported. The effects of different pre coating treatments on the gas permeance of the metallic ion cross linked PIM 1 TFC membrane are also discussed. The metallic ion cross linked PIM 1 TFC membrane displayed high CO2/N2 selectivity (23) and good CO2 permeance (1058 GPU)
Hongyong Zhao Lizhong Feng Xiaoli Ding Xiaoyao Tan Yuzhong Zhang
226323998
Triptycene based and nitrogen rich hyper cross linked polymers (TNHCPs) as efficient CO2 and iodine adsorbent
Abstract Triptycene based polymeric networks are rapidly emerging as porous organic polymers (POPs) for efficient capture of small gas molecules. Further, such triptycene based frameworks are also being explored as adsorbents for radioactive iodine. Herein, a group of three unique "Triptycene based and Nitrogen rich Hyper Crosslinked Polymers" (TNHCPs) have been easily obtained via the well known Friedel Craft alkylation reactions of triptycene with six membered N rich heterocycles. In these TNHCPs, the presence of triptycene motifs yields contorted and rigid polymeric frameworks with plenty of micropores and ultramicropores. Further, the presence of N rich heterocycles increases their efficiency to selectively capture carbon dioxide and adsorb iodine vapours as well as iodide ions from aqueous solutions. Comparison with data in recent literature reveals that TNHCPs are better in these domains than several previously reported POPs in general and HCPs in particular.
Atikur Hassan Santu Goswami Akhtar W Alam Ranajit Bera Neeladri Das
197196599
Removal of Heavy Metal Water Pollutants (Co2+ and Ni2+ Using Polyacrylamide/Sodium Montmorillonite (PAM/Na MMT) Nanocomposites
Nanocomposites composed of polyacrylamide and nanoclay were synthesized via free radical cross linking polymerization and used to adsorb Co2+ and Ni2+ ions from water. The polyacrylamide (PAM)/sodium montmorillonite (Na MMT) nanocomposites were characterized by Fourier transform infrared spectroscopy, X ray diffraction, and scanning electron microscopy to confirm the interaction between montmorillonite and the polymer matrix. The effects of pH and heavy metal ion concentration on the adsorption capacity of PAM/Na MMT were evaluated to determine suitable operating conditions for further experiments. Batch adsorption experimental data were fitted to Langmuir and Freundlich models, which provided information about the adsorption mechanism and the adsorbent surface. The highest Ni2+ removal yield was found to be 99.3% using the 2:1 (w/w) nanocomposite at pH 6 in 100 ppm of Ni2+ solution. The Co2+ removal yield was 98.7% at pH 6 in 60 ppm of Co2+ solution using the 4:1 (w/w) nanocomposite. These results were higher than those obtained by polyacrylamide and nanoclay under the same conditions (removal yield between 87.40 and 94.50% indicating that PAM/Na MMT nanocomposites remove heavy metal water pollutants more efficiently and can be used as a novel adsorbent for further industrial applications.
ACS omega
Kariana Andrea Moreno-Sader Alvaro Garcia-Padilla Alvaro Realpe Maria Acevedo-Morantes Joao B P Soares
104432319
CO2 sourced polycarbonates as solid electrolytes for room temperature operating lithium batteries
In the last few years, polycarbonates have been identified as alternatives to poly(ethylene oxide) as polymer electrolytes for lithium battery applications. In this work, we show the design of CO2 sourced polycarbonates for their use in room temperature operating lithium batteries. Novel functional polycarbonates with alternating oxo carbonate moieties and polyethylene oxide segments are synthesized by the facile room temperature (rt) organocatalyzed polyaddition of CO2 sourced bis(a alkylidene carbonate)s (bis aCCs) with polyethylene oxide diols. The effect of the molar mass of polyethylene oxide on the ionic conductivity and thermal properties of poly(oxo carbonate)s is investigated. The best candidate shows a low glass transition temperature of 44 degC and a high ionic conductivity of 3.75 x 10 5 S cm 1 at rt when loaded with 30 wt% bis(trifluoromethanesulfonyl)imide salt (LiTFSI) without any solvent. An all solid semi interpenetrated network polymer electrolyte (SIN SPE) is then fabricated by UV cross linking of a mixture containing specifically designed poly(oxo carbonate) bearing methacrylate pendants, diethylene glycol diacrylate and the previously described poly(oxo carbonate) containing LiTFSI. The resulting self standing membrane exhibits a high oxidation stability up to 5 V (vs. Li/Li+ an ionic conductivity of 1.1 x 10 5 S cm 1 at rt (10 4 S cm 1 at 60 degC) and promising mechanical properties. Assembled in a half cell configuration with LiFePO4 (LFP) as the cathode and lithium as the anode, the all solid cell delivers a discharge capacity of 161 mA h g 1 at 0.1C and 60 degC, which is very close to the theoretical capacity of LFP (170 mA h g 1) Also, a stable reversible cycling capacity over 400 cycles with a high coulombic efficiency of 99% is noted at 1C. Similar results are obtained at rt provided that 10 wt% tetraglyme as a plasticizer was added to the SIN SPE.
Farid Ouhib Leire Meabe Abdelfattah Mahmoud Nicolas Eshraghi Bruno Grignard J M Thomassin Abdelhafid Aqil Frederic Boschini Christine Jerome David Mecerreyes Christophe Detrembleur
199647557
Construction and carbon dioxide capture of microporous polymer networks with high surface area based on cross linkable linear polyimides
Microporous polyimides have been extensively investigated for gas capture and separation applications. Polyimides with intrinsic microporosity with contorted structures exhibit high surface areas. However, except for polyimides with intrinsic microporosity, most linear polyimides do not have microporous structures. Here, a crosslinked structure is introduced into linear polyimides to construct microporous polyimide networks with high surface areas. It is intriguingly found that the surface areas of the microporous polyimide networks increased by about ten times compared with the uncrosslinked polyimides; they are in the range of 635 727 m2 g 1 and among the best reported results for linear polyimides with intrinsic microporosity. TF PI CL and 6FA PI CL can respectively adsorb 10.03 and 7.28 wt% CO2 (273 K/1 bar) Meanwhile, the CO2/N2 and CO2/CH4 selectivities of TF PI CL are 58.4 and 12.9, respectively. This work reveals that the introduction of a crosslinked structure is an effective method of fabricating microporous polyimide networks with high surface area and highly selective CO2 capture capacity based on linear polyimides, which is crucial for CO2 capture and storage.
Ningning Song Tianjiao Wang Hongyan Yao Tengning Ma Kaixiang Shi Ye Tian Yongcun Zou Shiyang Zhu Yunhe Zhang Shaowei Guan
103487022
Triptycene based microporous polymers (TMPs) Efficient small gas (H2 and CO2) storage and high CO2/N2 selectivity
Abstract In contemporary research, there is a growing interest in the development of novel porous materials that can be used as adsorbents for small gas molecules such as CO2 and H2. This is important from a perspective of more efficient energy alternative and a cleaner environment. Hyper cross linked polymers are a subclass of microporous organic polymers that are also reportedly known to efficiently adsorb H2 and CO2. In this context, triptycene based microporous polymers are known to exhibit high gas storage and separation properties. Herein, facile synthesis of a set of three triptycene based microporous polymers (TMPs) is described. TMPs were prepared by crosslinking triptycene monomers with various (bromomethyl)benzene units using AlCl3 catalyzed Friedel Crafts alkylation reactions in high yield. Gas uptake experiments indicate that TMPs are microporous having moderately high surface areas (up to 1372 m2 g 1) Interestingly, TMP3 demonstrated very high reversible adsorption of molecular H2 (2.21% by mass at 1 bar/77 K) and it may be considered in the league of porous organic frameworks demonstrating outstanding H2 uptake at low pressure. Simultaneously, these polymers also show quite high CO2 uptake at 273 K and 1 bar (up to 223 mg g 1) Additionally TMPs have also exhibited very high CO2/N2 gas selectivity (up to 70) Considering the facile synthetic protocol of TMPs (mandatory for scale up synthesis) large H2 and CO2 uptake and concurrent high CO2/N2 (up to 70) selectivity, these are potential materials for clean energy applications.
Ranajit Bera Snehasish Mondal Neeladri Das