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Surface-functionalized polymeric microspheres have wide applications in various areas. Herein, monodisperse poly(styrene–methyl methacrylate–acrylic acid) (PSMA) microspheres were prepared via emulsion polymerization. Polyaniline (PANI) was then coated on the PSMA surface via in situ polymerization, and a three-dimensional (3D) structured reticulate PANI/PSMA composite was, thus, obtained. The adsorption performance of the composite for organic dyes under different circumstances and the adsorption mechanism were studied. The obtained PANI/PSMA composite exhibited a high adsorption rate and adsorption capacity, as well as good adsorption selectivity toward methyl orange (MO). The adsorption process followed pseudo-second-order kinetics and the Langmuir isotherm. The maximum adsorption capacity for MO was 147.93 mg/g. After five cycles of adsorption–desorption, the removal rate remained higher than 90%, which indicated that the adsorbent has great recyclability. The adsorbent materials presented herein would be highly valuable for the removal of organic dyes from wastewater.

Shape-memory epoxy resin (SMER) with strong mechanical properties have potential for a wide range of applications, but the design and synthesis of SMER with both high mechanical property and short shape recovery time are still a challenge. Hyperbranched epoxy resin shape-memory materials offer a unique approach that has been investigated by very few researchers because of the tedious synthetic process. In this work, serial hyperbranched epoxy resins with different molecular weights and structures (ETMP-n, ETHP-n, n = 6, 9, 11) were synthesized by a simple highly efficient thiol-maleimide click reaction. Cured ETHP-n films display shape fixity ratios and shape recovery ratios as high as 98.5% and 97.2% after seven shape-memory cycles, respectively. Cured ETMP-9 and ETHP-9 films demonstrate rapid response, with shape recovery times as short as 450 and 430 ms, respectively, which are significantly shorter than previously reported shape-memory epoxy resins. The maximum actuated stress of cured films reaches 0.72 MPa, which was much higher than that of most mammalian skeletal muscles (0.35 MPa). Cured ETHP-9 films exhibited higher shape-memory performances than cured ETMP-9 films because of nitrogen heterocyclic rigid structures, appropriately high crosslink density and narrower molecular weight distribution. These excellent shape-memory performances make the hyperbranched epoxy resins suitable for practical applications in microelectronic devices and artificial muscles.

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