Organized spontaneous emulsification (OSE) produces ordered water-in-oil-in-water (W/O/W) multiple emulsion droplets stabilized by bottlebrush block copolymer (BBCP) surfactants, such as (polynorbornene-g-polystyrene)...Organized spontaneous emulsification (OSE) produces ordered water-in-oil-in-water (W/O/W) multiple emulsion droplets stabilized by bottlebrush block copolymer (BBCP) surfactants, such as (polynorbornene-g-polystyrene)-b-(polynorbornene-g-polyethylene oxide) (PS-b-PEO), templating ordered porous particles with visible structural colors. Here, homopolymer polystyrenes (hPS) were used to swell the PS domain and thus to effectively increase the W/O interfacial curvature of the internal droplets. By variation of hPS concentration, pore diameter is largely tunable from 34 to over 210 nm, leading to tunable photonic bandgaps in the whole visible spectrum. The ratio (α) of molecular weight of hPS relative to that of the PS side chains of the BBCP can greatly influence their spatial distribution within the PS domain. For α ≤ 1, uniform solubilization of the hPS chains into the side chains of BBCP is achieved leading to a homogeneous porous structure. For α > 1, local solubilization of the hPS chains at interface of the internal droplets is disclosed at relatively low concentrations of hPS (≤ 42 wt%), resulting in a small change in pore diameter. For contrast, a rapid increase of the W/O interfacial curvature was observed upon further increase of the hPS content (> 42 wt%) through an evident influence on the OSE procedure.展开更多
High transparency and toughness are prerequisites for sustainable polymers if they are to find wide application as alternatives to petroleum-based polymers.However,the utility of sustainable polymers such as commercia...High transparency and toughness are prerequisites for sustainable polymers if they are to find wide application as alternatives to petroleum-based polymers.However,the utility of sustainable polymers such as commercially available polylactide(PLA)is limited by their inherent brittleness and high cost.Unfortunately,toughening PLA-based materials via cost-effective blending strategies without sacrificing transparency remains a challenge.Herein,we report a novel strategy involving active refractive index matching for creation of highly transparent and tough PLA blends.Specifically,we engineered the refractive index of a promising renewable poly(epichlorohydrin-co-ethylene oxide)elastomer by introducing polar ionic moieties via a simple chemical method,and we blended the resulting ionomers with PLA.The best blend showed an impact strength of>80 kJ/m2,an elongation at break of 400%,and high transparency(90%).These characteristics are of great importance for potential applications such as packaging.Our strategy offers a versatile new way to prepare high-performance sustainable polymer materials with excellent transparency.展开更多
基金supported financially by the National Natural Science Foundation of China(Grant No.22071176&52273214).
文摘Organized spontaneous emulsification (OSE) produces ordered water-in-oil-in-water (W/O/W) multiple emulsion droplets stabilized by bottlebrush block copolymer (BBCP) surfactants, such as (polynorbornene-g-polystyrene)-b-(polynorbornene-g-polyethylene oxide) (PS-b-PEO), templating ordered porous particles with visible structural colors. Here, homopolymer polystyrenes (hPS) were used to swell the PS domain and thus to effectively increase the W/O interfacial curvature of the internal droplets. By variation of hPS concentration, pore diameter is largely tunable from 34 to over 210 nm, leading to tunable photonic bandgaps in the whole visible spectrum. The ratio (α) of molecular weight of hPS relative to that of the PS side chains of the BBCP can greatly influence their spatial distribution within the PS domain. For α ≤ 1, uniform solubilization of the hPS chains into the side chains of BBCP is achieved leading to a homogeneous porous structure. For α > 1, local solubilization of the hPS chains at interface of the internal droplets is disclosed at relatively low concentrations of hPS (≤ 42 wt%), resulting in a small change in pore diameter. For contrast, a rapid increase of the W/O interfacial curvature was observed upon further increase of the hPS content (> 42 wt%) through an evident influence on the OSE procedure.
基金supported by the National Natural Science Foundation of China(No.51573130)。
文摘High transparency and toughness are prerequisites for sustainable polymers if they are to find wide application as alternatives to petroleum-based polymers.However,the utility of sustainable polymers such as commercially available polylactide(PLA)is limited by their inherent brittleness and high cost.Unfortunately,toughening PLA-based materials via cost-effective blending strategies without sacrificing transparency remains a challenge.Herein,we report a novel strategy involving active refractive index matching for creation of highly transparent and tough PLA blends.Specifically,we engineered the refractive index of a promising renewable poly(epichlorohydrin-co-ethylene oxide)elastomer by introducing polar ionic moieties via a simple chemical method,and we blended the resulting ionomers with PLA.The best blend showed an impact strength of>80 kJ/m2,an elongation at break of 400%,and high transparency(90%).These characteristics are of great importance for potential applications such as packaging.Our strategy offers a versatile new way to prepare high-performance sustainable polymer materials with excellent transparency.
