Poly(ether-block-amide) membrane with deformability and adjustable surface hydrophilicity for water purification
About: This article is published in Polymer Engineering and Science.The article was published on 2021-06-17. It has received 2 citations till now. The article focuses on the topics: Block (telecommunications).
Citations
More filters
TL;DR: In this paper , a series of cellulose acetate (CA) ultrafiltration membranes with different pore morphology and structure were successfully prepared by combining solution casting, non-solvent-induced phase inversion, and pore-forming agent leached out technologies.
Abstract: To solve the easy contamination problem of ultrafiltration membranes during protein separation, a series of cellulose acetate (CA) ultrafiltration membranes with different pore morphology and structure were successfully prepared by combining solution casting, non-solvent-induced phase inversion, and pore-forming agent leached out technologies. The effects of molecule weight and the content of porogen polyethylene glycol (PEG) on the pore morphology, chemical composition, and wettability of the CA ultrafiltration membrane were systematically studied. The feed permeability, bovine serum albumin rejection, and anti-fouling ability were also investigated. The results showed that the CA10k membrane has the highest pure water flux of 877.5 L/m2h.bar, largest bovine serum albumin (BSA) rejection of 96.5% and flux recovery rate of 90.9% when the PEG molecule weight and content are 10 kDa and 10 wt%. Those results showed that the CA ultrafiltration membranes have great application prospects in the BSA separation area.
TL;DR: In this paper , a commercial multiblock copolymer (poly(etherblock-amide)), consisting of 40% rigid amide (PA6) groups and 60% flexible ether (PEO) linkages, was selected as the base polymer for preparing dense flat sheet mixed matrix membranes (MMMs) using the solution casting method.
Abstract: In the present work, Pebax-1657, a commercial multiblock copolymer (poly(ether-block-amide)), consisting of 40% rigid amide (PA6) groups and 60% flexible ether (PEO) linkages, was selected as the base polymer for preparing dense flat sheet mixed matrix membranes (MMMs) using the solution casting method. Carbon nanofillers, specifically, raw and treated (plasma and oxidized) multi-walled carbon nanotubes (MWCNTs) and graphene nanoplatelets (GNPs) were incorporated into the polymeric matrix in order to improve the gas-separation performance and polymer’s structural properties. The developed membranes were characterized by means of SEM and FTIR, and their mechanical properties were also evaluated. Well-established models were employed in order to compare the experimental data with theoretical calculations concerning the tensile properties of MMMs. Most remarkably, the tensile strength of the mixed matrix membrane with oxidized GNPs was enhanced by 55.3% compared to the pure polymeric membrane, and its tensile modulus increased 3.2 times compared to the neat one. In addition, the effect of nanofiller type, structure and amount to real binary CO2/CH4 (10/90 vol.%) mixture separation performance was evaluated under elevated pressure conditions. A maximum CO2/CH4 separation factor of 21.9 was reached with CO2 permeability of 384 Barrer. Overall, MMMs exhibited enhanced gas permeabilities (up to fivefold values) without sacrificing gas selectivity compared to the corresponding pure polymeric membrane.
References
More filters
TL;DR: A facile approach to produce lightweight microcellular polyetherimide (PEI)/graphene nanocomposite foams with a density of about 0.3 g/cm3 is reported by a phase separation process.
Abstract: We report a facile approach to produce lightweight microcellular polyetherimide (PEI)/graphene nanocomposite foams with a density of about 0.3 g/cm3 by a phase separation process. It was observed that the strong extensional flow generated during cell growth induced the enrichment and orientation of graphene on cell walls. This action decreased the electrical conductivity percolation from 0.21 vol % for PEI/graphene nanocomposite to 0.18 vol % for PEI/graphene foam. Furthermore, the foaming process significantly increased the specific electromagnetic interference (EMI) shielding effectiveness from 17 to 44 dB/(g/cm3). In addition, PEI/graphene nanocomposite foams possessed low thermal conductivity of 0.065–0.037 W/m·K even at 200 °C and high Young’s modulus of 180–290 MPa.
659 citations
TL;DR: In this article, a 3D copper nanowires-thermally annealed graphene aerogel (CuNWs-TAGA) framework is firstly prepared by freeze-drying followed by thermal annealing from CuNWs, graphene oxide (GO) and Lascorbic acid.
Abstract: 3D copper nanowires-thermally annealed graphene aerogel (CuNWs-TAGA) framework is firstly prepared by freeze-drying followed by thermal annealing from CuNWs, graphene oxide (GO) and L-ascorbic acid. Epoxy resin is then poured back into the above 3D CuNWs-TAGA framework to fabricate the CuNWs-TAGA/epoxy nanocomposites. CuNWs with average diameter of about 120 nm and length of approximate 10 μm are successfully prepared. When the mass fraction of CuNWs-TAGA is 7.2 wt% (6.0–1.2 wt% CuNWs-TAGA), the thermal conductivity coefficient (λ) value of the CuNWs-TAGA/epoxy nanocomposites reaches the maximum of 0.51 W/mK. Meantime, the CuNWs-TAGA/epoxy nanocomposites exhibit the maximum electromagnetic interference shielding effectiveness (EMI SE) value of 47 dB and electrical conductivity (σ) of 120.8 S/m, ascribed to perfect 3D CuNWs-TAGA conductive network structures. Meanwhile, the corresponding elasticity modulus, hardness, glass transition temperature (Tg) and heat-resistance index (THRI) of the CuNWs-TAGA/epoxy nanocomposites increase to 4.69 GPa, 0.33 GPa, 126.3 °C and 181.7 °C, respectively.
482 citations
TL;DR: In this paper, hierarchical composite nanoparticles of multiwall carbon nanotube (MWCNT)-Fe3O4@Ag combining electrical conductivity and magnetism were obtained from acylamine reaction between carboxylation of Fe3O 4@Ag (Fe3OnAg-COOH) nanoparticles and amino functionalized MWCNTs.
379 citations
TL;DR: A naturally abundant biomass, konjac glucomannan, together with simple-to-fabricate iron-based metal-organic framework-derived photothermal nanoparticles is introduced into the polyvinyl alcohol networks, building hybrid hydrogel evaporators in a cost-effective fashion.
Abstract: Solar vapor generation has presented great potential for wastewater treatment and seawater desalination with high energy conversion and utilization efficiency. However, technology gaps still exist for achieving a fast evaporation rate and high quality of water combined with low-cost deployment to provide a sustainable solar-driven water purification system. In this study, a naturally abundant biomass, konjac glucomannan, together with simple-to-fabricate iron-based metal-organic framework-derived photothermal nanoparticles is introduced into the polyvinyl alcohol networks, building hybrid hydrogel evaporators in a cost-effective fashion ($14.9 m-2 of total materials cost). With advantageous features of adequate water transport, effective water activation, and anti-salt-fouling function, the hybrid hydrogel evaporators achieve a high evaporation rate under one sun (1 kW m-2 ) at 3.2 kg m-2 h-1 out of wastewater with wide degrees of acidity and alkalinity (pH 2-14) and high-salinity seawater (up to 330 g kg-1 ). More notably, heavy metal ions are removed effectively by forming hydrogen and chelating bonds with excess hydroxyl groups in the hydrogel. It is anticipated that this study offers new possibilities for a deployable, cost-effective solar water purification system with assured water quality, especially for economically stressed communities.
371 citations
TL;DR: In this paper, an analogue calorimetry for blends of poly(vinyl ester)s and polyacrylates has been studied, and it is found that isomeric esters differing only in the orientation of the COO group mix with only small heat change, which can be positive or negative.
Abstract: Analogue calorimetry for blends of poly(vinyl ester)s and polyacrylates has been studied. Hydrogenated monomers were used as analogues of the corresponding polymers. It is found that isomeric esters differing only in the orientation of the COO group mix with only small heat change, which can be positive or negative. The values of the interaction energy density, B12 (in cal/cm3), are −0.045, 0.031, and −0.076, respectively, for the following binary mixtures; ethyl acetate + methyl propionate, n-propyl propionate + ethyl butyrate, and phenyl propionate + ethyl benzoate. The negative heat of mixing for the two pairs of very similar liquids, although unexpected, explains why the corresponding polymers are miscible. The small positive heat of mixing for the other pair is sufficient to predict demixing of the corresponding polymers, viz., poly(n-propyl acrylate) and poly(vinyl butyrate), which contradicts the observation of their homogeneous mixing. This suggests that hydrogenated monomers are not always the pr...
248 citations