Thin-film composite (TFC) nanofiltration (NF) membranes were fabricated via the interfacial polymerization of piperazine (PIP) and 1,3,5-benzenetricart)oiiyl trichloride on polysulfone (PSf) support membranes blended ...Thin-film composite (TFC) nanofiltration (NF) membranes were fabricated via the interfacial polymerization of piperazine (PIP) and 1,3,5-benzenetricart)oiiyl trichloride on polysulfone (PSf) support membranes blended with K^+-responsive poly(N-isopropylacryamideco- acryloylamidobenzo-15-crown-5)(P(NIPAM-co- AAB15C5)). Membranes were characterized by attenuated total reflection Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, atomic force microscope, scanning electron microscope, contact angle, and filtration tests. The results showed that:(1) Under K^+-free conditions, the blended P(NIPAM-co-AAB15C5)/PSf supports had porous and hydrophilic surfaces, thereby producing NF membranes with smooth surfaces and low MgSO4 rejections;(2) With K^+ in the PIP solution, the surface roughness and water permeability of the resultant NF membrane were increased due to the K^+-induced transition of low-content P(NIPAM-co-AAB15C5) from hydrophilic to hydrophobic;(3) After a curing treatment at 95℃, the improved NF membrane achieved an even higher pure water permeability of 10.97 L·m^-2·h^-1 - bar1 under 200 psi. Overall, this study provides a novel method to improve the performance of NF membranes and helps understand the influence of supports on TFC membranes.展开更多
Human muscles are notably toughened or softened with specific inorganic ions.Inspired by this phenomenon,herein we report a simple strategy to endow hydrogels with comparable ion-responsive mechanical properties by tr...Human muscles are notably toughened or softened with specific inorganic ions.Inspired by this phenomenon,herein we report a simple strategy to endow hydrogels with comparable ion-responsive mechanical properties by treating the gels with different ionic solutions.Semi-crystalline poly(vinyl alcohol)hydrogels are chosen as examples to illustrate this concept.Similar to muscles,the mechanical property of hydrogels demonstrates strong dependence on both the nature and concentration of inorganic ions.Immersed at the same salt concentration,the hydrogels treated with different ionic solutions manifest a broad-range tunability in rigidity(Young’s modulus from 0.16 to 9.6 MPa),extensibility(elongation ratio from 100% to 570%),and toughness(fracture work from 0.82 to 35 MJm^(-3)).The mechanical property well follows the Hofmeister series,where the“salting-out”salts(kosmotropes)have a more pronounced effect on the reinforcement of the hydrogels.Besides,the hydrogels’mechanical performance exhibits a positive correlation with the salt concentration.Furthermore,it is revealed both the polymer solubility from amorphous domains and polymer crystallinity from crystalline domains are significantly influenced by the ions,which synergistically contribute to the salt-responsive mechanical performance.Benefitting from this feature,the hydrogels have demonstrated promising industrial applications,including tunable tough engineering soft materials,anti-icing coatings,and soft electronic devices.展开更多
基金the National Natural Science Foundation of China (Grant No.51678377)Sichuan University Outstanding Youth Foundation (2015SCU04A35)+1 种基金Applied Basic Research of Sichuan Province (2017JY0238)Key Projects in the Science & Technology Program of Hainan Province (zdkj2016022).
文摘Thin-film composite (TFC) nanofiltration (NF) membranes were fabricated via the interfacial polymerization of piperazine (PIP) and 1,3,5-benzenetricart)oiiyl trichloride on polysulfone (PSf) support membranes blended with K^+-responsive poly(N-isopropylacryamideco- acryloylamidobenzo-15-crown-5)(P(NIPAM-co- AAB15C5)). Membranes were characterized by attenuated total reflection Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, atomic force microscope, scanning electron microscope, contact angle, and filtration tests. The results showed that:(1) Under K^+-free conditions, the blended P(NIPAM-co-AAB15C5)/PSf supports had porous and hydrophilic surfaces, thereby producing NF membranes with smooth surfaces and low MgSO4 rejections;(2) With K^+ in the PIP solution, the surface roughness and water permeability of the resultant NF membrane were increased due to the K^+-induced transition of low-content P(NIPAM-co-AAB15C5) from hydrophilic to hydrophobic;(3) After a curing treatment at 95℃, the improved NF membrane achieved an even higher pure water permeability of 10.97 L·m^-2·h^-1 - bar1 under 200 psi. Overall, this study provides a novel method to improve the performance of NF membranes and helps understand the influence of supports on TFC membranes.
基金supported by the National Natural Science Foundation of China(51903253)the Natural Science Foundation of Guangdong Province of China(2019A1515011150 and 2019A1515011258)the Science and Technology Development Fund of Macao(FDCT 0083/2019/A2).
文摘Human muscles are notably toughened or softened with specific inorganic ions.Inspired by this phenomenon,herein we report a simple strategy to endow hydrogels with comparable ion-responsive mechanical properties by treating the gels with different ionic solutions.Semi-crystalline poly(vinyl alcohol)hydrogels are chosen as examples to illustrate this concept.Similar to muscles,the mechanical property of hydrogels demonstrates strong dependence on both the nature and concentration of inorganic ions.Immersed at the same salt concentration,the hydrogels treated with different ionic solutions manifest a broad-range tunability in rigidity(Young’s modulus from 0.16 to 9.6 MPa),extensibility(elongation ratio from 100% to 570%),and toughness(fracture work from 0.82 to 35 MJm^(-3)).The mechanical property well follows the Hofmeister series,where the“salting-out”salts(kosmotropes)have a more pronounced effect on the reinforcement of the hydrogels.Besides,the hydrogels’mechanical performance exhibits a positive correlation with the salt concentration.Furthermore,it is revealed both the polymer solubility from amorphous domains and polymer crystallinity from crystalline domains are significantly influenced by the ions,which synergistically contribute to the salt-responsive mechanical performance.Benefitting from this feature,the hydrogels have demonstrated promising industrial applications,including tunable tough engineering soft materials,anti-icing coatings,and soft electronic devices.
