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Continuous preparation of the intumescent flame retardant (IFR) and polypropylene (PP) composite (IFR‐PP) foams with excellent flame retardancy and mechanical properties via the extrusion assisted by subcritical CO2 was presented. The effects of die structure, die temperature/pressure and CO2 injection ratios on expansion ratio, cell diameter, and cell density of the IFR‐PP foams were investigated. A uniform cell structure without obvious defects was prepared by the die with better pressure holding capacity. With the increase of die temperature, die pressure decreased accordingly, the expansion ratio of the obtained IFR‐PP foams decreased, the cell diameter increased, and the cell density decreased. With an appropriate increase in the CO2 injection ratio, the expansion ratio of the resulting IFR‐PP foams increased, the cell diameter decreased, and the cell density increased. Cell wall thickness played an important role in mechanical properties. When the expansion ratio was maintained near 3 or cell diameter was maintained near 92 μm, as the cell wall thickness increased, the tensile modulus and tensile strength increased. A cell structure without defects possessed better mechanical properties and flame retardancy than a deformed cell. Moreover, the IFR‐PP foams exhibiting excellent flame retardancy including the 30% of limiting oxygen index (LOI) values and UL‐94 V0 rating without dripping were achieved at only 22.5 wt% of IFR loading. [ABSTRACT FROM AUTHOR]

Polysilsesquioxane-polyacrylate/silica hybrid latexes (PSQ-PAS) with high silicon content were prepared by directly mixing colloidal silica with polysilsesquioxane-polyacrylate emulsion (PSQ-PA), which was prepared through seeded emulsion polymerization using polymethacryloxypropylsilsesquioxanes as the core and polyacrylate (PA) as the shell respectively. The chemically bonded PSQ-PAS thin films were obtained via sol-gel process after addition of hydrophilic cosolvent to PSQ-PAS emulsion and subsequent drying at room temperature. The effects of silica/PSQ-PA ratio (w/w) on the film properties of hardness, optical property and thermal stability were investigated. Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS) and transmission electron microscopy (TEM) were used to characterize the chemical composition and morphology of the resultant hybrid particles. DLS and TEM results indicated that both PSQ and PSQ-PA particles had narrow size distribution and their average diameters were about 200 and 350 nm, respectively. Pendulum durometer, UV-vis spectroscopy, and thermogravimetric analysis (TGA) were used to characterize the hardness, optical property and thermal stability of PSQ-PAS latex films. The results showed that the PSQ-PAS films hardness increased with the increasing ratio of silica/PSQ-PA, whereas the transmittance decreased slightly. TGA curves demonstrated PSQ-PAS films displayed excellent thermal stability, and the residual silicon weight exceeded 30%. POLYM. COMPOS., 36:389-396, 2015. © 2014 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Recently, solar-driven interfacial evaporation (SDIE) has been developed quickly for low-cost and sustainable seawater desalination, but addressing the conflict between a high evaporation rate and salt rejection during SDIE is still challenging. Here, a spatial confinement strategy is proposed to prepare the gel composite solar evaporator (SCE) by loading one thin hydrogel layer onto the skeleton of a carbon aerogel. The SCE retains the hierarchically porous structure of carbon aerogels with an optimized water supply induced by dual-driven forces (capillary effects and osmotic pressure) and takes advantage of both aerogels and hydrogels, which can gain energy from air and reduce water enthalpy. The SCE has a high evaporation rate (up to 4.23 kg m -2  h -1 under one sun) and excellent salt rejection performance and can maintain structural integrity after long-term evaporation even at high salinities. The SDIE behavior, including heat distribution, water transport, and salt ion distribution, is investigated by combining theoretical simulations and experimental results. This work provides new inspiration and a theoretical basis for the development of high-performance interfacial evaporators., (© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Conductive organohydrogels are promising for strain sensing, while their weak mechanical properties, poor crack propagation resistance and unstable sensing signals during long-term use have seriously limited their applications as high-performance strain sensors. Here, we propose a facile method, i.e. , solvent exchange assisted hot-pressing, to prepare strong yet tough, transparent and anti-fatigue ionically conductive organohydrogels (ICOHs). The densified polymeric network and improved crystallinity endow ICOHs with excellent mechanical properties. The tensile strength, toughness, fracture energy and fatigue threshold of ICOHs can reach 36.12 ± 4.15 MPa, 54.57 ± 2.89 MJ m -3 , 43.44 ± 8.54 kJ m -2 and 1212.86 ± 57.20 J m -2 , respectively, with a satisfactory fracture strain of 266 ± 33%. In addition, ICOH strain sensors with freezing and drying resistance exhibit excellent cycling stability (10 000 cycles). More importantly, the fatigue resistance allows the notched strain sensor to work normally with no crack propagation and output stable and reliable sensing signals. Overall, the unique flaw-insensitive strain sensing makes ICOHs promising in the field of wearable and durable electronics.