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Chemically synthesized poly(4-hydroxybutyrate) (P4HB) is a new generation of biomass-derived and degradable semi-crystalline polymer with good comprehensive properties, but high costs limit its application. Starch, as an inexpensive natural polymer, can reduce the cost of P4HB products. However, starch lacks thermoplastic behavior and has poor compatibility with P4HB, thus its extensive use will inevitably impair the mechanical properties of P4HB. In this study, the ball-milling starch grafting process is adopted, which can simultaneously solve the two major deficiencies of starch, and the prepared ball-milling starch-g-polycaprolactone (BSt-g-PCL) has thermoplasticity and better compatibility with P4HB. BSt-g-PCL can melt near 55 °C, and the interweaving of its molecular chains with P4HB reduces the binding energy (E interaction) of both, making the phase interface blurred or even disappear. Therefore, the elongation at break retention (R EB) of P4HB/BSt-g-PCL can increase from 37.1 % to 74.3 % compared to P4HB/starch at the same filling (70 Phr). Additionally, BSt-g-PCL can exert the effect of accelerating P4HB degradation and still make it maintain excellent anti-aging ability. The ball-milling starch graft process provides a simple and effective method for the preparation of inexpensive fully biodegradable P4HB composite films with excellent mechanical properties. [Display omitted] [ABSTRACT FROM AUTHOR]

Although the utilization of solar photothermal gain (SPG) (0.28μm–2.5 μm) or infrared radiation cooling (IRC) (2.5 μm–25 μm) enables the thermochromic smart window to play a role in decreasing building energy consumption, the fragmented current research on these properties unfortunately leads to a low efficacy. Herein, based on the simulation of SPG and IRC properties on building energy consumption, a tailored hydrogel is employed in a reversible glass mold with anisotropic infrared radiation emission (ε) in the different surfaces, successfully integrating excellent SPG parameters (phase transition temperature (τ C), 28 ° C , post-phase solar transmittance (T sol − HT), 3.52%) and IRC parameters (switchable infrared emissivity (Δε), 0.75–0.90). By utilizing summer and winter climate data from Wenzhou, as well as annual climate data from Singapore and Helsinki, it is determined that this gel window may save up to 64.68 MJ/m2, 11.31 MJ/m2, 201.84 MJ/m2, and 60.16 MJ/m2 in the respective locations, when compared to regular glass using the same model in EnergyPlus software. With the exceptional pre-phase visible light transmittance (T lum − LT = 84.86 %) and building energy saving performance, the all-day and all-region smart window deserves attention, further investigation, and discourse for alleviating the energy crisis and mitigating greenhouse emissions. • A low energy consumption smart window with high transmittance. • Both SPG and IRC jointly reduce the energy consumption. • The SPG includes τ C and T sol − HT , which are 28.79 °C and 3.52%, respectively. • The IRC ability has a large control range (Δε , 0.75–0.90). [ABSTRACT FROM AUTHOR]

Regulating the selective distribution of functional fillers in polymer blends is an effective way to improve the properties of materials. In this paper, the directional migration and selective distribution of SiO 2 particles within polycarbonate (PC)/poly (styrene- co -acrylonitrile) (SAN) microparts were observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), which are correlated with the multiple scattering effect and the light-scattering performance. Compared with the undirected migration, when SiO 2 (2.00 × 10−2 g/cm3) migrated into the SAN phase, the scattering angle of the composites increased by 22.75%, and the scattering patterns and scattering surfaces also improved significantly. We believe that the multiple scattering of SiO 2 particles greatly improved the scattering ability of the material under the limited volume of the SAN phase, which can provide new methods and ideas for the preparation of light-scattering materials with comprehensive performance. [Display omitted] [ABSTRACT FROM AUTHOR]

In this work, based the perspective of thermodynamics and dynamics theory, we used a simple, convenient and green melt blending method to prepare polycarbonate (PC)/poly (styrene-co-acrylonitrile) (SAN)-SiO 2 light-scattering materials containing "pomegranate-like" SAN-SiO 2 microspheres. The small spherical particles (SiO 2) of the composite microspheres could produce multiple scattering effect, reducing the direct transmittance and increasing the scattering transmittance, which greatly improved the light-scattering performance of the material. The effective scattering range and scattering uniformity of the material were obviously improved on the premise that the transmittance and haze slightly lost even increased. In addition, due to the limited volume, the selective distribution of SiO 2 particles in the SAN dispersed phases greatly reduced the percolation threshold of the scattering angle by 65%. In short, this work provided a light-scattering material with excellent light-scattering performance and mechanical properties, which was expected to be made into a thin and effective light-scattering film for large-screen display, flexible lighting and other fields. Image 1 [ABSTRACT FROM AUTHOR]

• A total of 267 water and sediment samples were taken from 45 sampling sites along the Yellow River in the spring and autumn. • The spatial patterns of bacterial community were explored with different habitats in the Yellow River. • Species sorting and dispersal limitation were key factors for water and sediment bacterial communities, respectively. • For community coalescence, the same and similar habitats had higher proportions of overlapped species. • Bacteria attached to suspended particles may facilitate community coalescence in a large sediment-laden river. Many studies have reported the influence of dispersal processes on aquatic bacterial communities, but the role of community coalescence is still unknown in sediment-laden rivers. Here, we examined the assembly of distinctive bacterial communities (free-living [FL], particle-attached [PA], and surface-sediment [SS]) with differing habitat preferences across different regions of the Yellow River (China) in the spring and autumn of 2019. We demonstrated that in both seasons SS bacteria featured the highest diversity, followed by PA bacteria, and then FL bacteria. Nonetheless, both FL and PA groups showed remarkable seasonal variation in water samples, while the SS group in sediment samples showed significant spatial variation. Furthermore, species sorting and dispersal limitation respectively governed the biogeographic patterns (strong distance–decay relationships) of water and sediment bacterial communities. With respect to community coalescence, not only the same habitats (i.e., water–water, particle–particle, and sediment–sediment) but also similar habitats (i.e., water–particle) had higher proportions of overlapped amplicon sequence variants (ASVs) compared with different habitats (i.e., water–sediment and particle–sediment). Moreover, the proportions of overlapped ASVs between PA and SS groups were higher than those between FL and SS groups. Network analysis revealed that the SS group harbored the highest network complexity, followed by PA and FL groups. Most connectors in the networks were identified as FL–PA–SS ASVs irrespective of the river reaches sampled. These findings demonstrate the biogeographic patterns of distinctive bacterial communities driven by species sorting and dispersal limitation, and provide evidence for bacterial community coalescence in the Yellow River's water and sediment. Bacteria attached to suspended particles may play a paramount role in the microbial ecology of different habitats in large sediment-laden rivers. [ABSTRACT FROM AUTHOR]