A rational integration of multiple reactive centers into a combined unit to facilitate their cooperative effects is a smart approach for accelerating the catalytic activity.Here,to achieve this goal,linear imidazolium...A rational integration of multiple reactive centers into a combined unit to facilitate their cooperative effects is a smart approach for accelerating the catalytic activity.Here,to achieve this goal,linear imidazolium-based ionic polymers were confined into the nanopores of mesoporous silica nanospheres anchored with homogeneously distributed zinc salts.Owing to the flexible character and the reinforced cooperative effects of the ionic liquid(nucleophile)and zinc species(Lewis acid)in the confined mesoporous structure,the resultant composite exhibited dramatically improved catalytic performance in the cycloaddition of CO2 with epoxides to form cyclic carbonates.This was in contrast to that observed for the individual catalytic components.Moreover,such a solid catalyst could be easily recovered and reused four times without a significant loss of activity.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supported by the National Natural Science Foundation of China(201573136,21603128,U1510105)the Natural Science Foundation for Young Scientists of Shanxi Province(2016021034)the Scientific Research Start-up Funds of Shanxi University(RSC723)~~
文摘A rational integration of multiple reactive centers into a combined unit to facilitate their cooperative effects is a smart approach for accelerating the catalytic activity.Here,to achieve this goal,linear imidazolium-based ionic polymers were confined into the nanopores of mesoporous silica nanospheres anchored with homogeneously distributed zinc salts.Owing to the flexible character and the reinforced cooperative effects of the ionic liquid(nucleophile)and zinc species(Lewis acid)in the confined mesoporous structure,the resultant composite exhibited dramatically improved catalytic performance in the cycloaddition of CO2 with epoxides to form cyclic carbonates.This was in contrast to that observed for the individual catalytic components.Moreover,such a solid catalyst could be easily recovered and reused four times without a significant loss of activity.
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.
