Ag nanoparticles were successfully prepared using a liquid reduction method with a suitable mixture reductant of polyethylene glycol (PEG) and ethylene glycol (EG). OP-10 as a dispersing agent, was used to prepare the conductive Ag ink. Ag nanoparticles with an average particle size of 40 nm were prepared while the ratio of PEG to EG was 1:2. Meanwhile, the Ag particles had a narrow size distribution and great dispersion performance. The effects of paper substrates, sintering temperature, and sintering time on the conductivity of the printed Ag ink pattern were also studied. It was found that Lucky porous high glossy photo paper was a good candidate as the printing substrate. The resistivity of the printed pattern could reach 5.1 × 10−3 Ω·cm after heated at 100 °C for 2 h. Hence, the printed pattern showed good conductivity which led to the LED light being on. Furthermore, the Ag nanoparticle ink could be printed to form any pattern as required that still showed good electrical conductivity after being sintered under low-temperature. This could provide new possibilities for the preparation of flexible electrodes.

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Fabrication and performance of the castor oil (CO)‐based hyperbranched acrylate (C20AA) UV‐curable coatings are highlighted in this work. Herein, C20AA was obtained through a facile reaction of a castor oil‐based hyperbranched polyol (C20) with acrylic acid. FT‐IR and 1H NMR spectra confirmed the synthesis of the target C20AA. Subsequently, the as‐prepared C20AA was employed for crosslinking a commercialized linear polyurethane acrylate (PUA) UV‐curable oligomer. Specifically, by varying the content of C20AA over the range of 0, 20, 40, and 60 wt%, a series of UV‐curable coatings were prepared and coded as C20AA‐0, C20AA‐20, C20AA‐40, and C20AA‐60, respectively, which were further cured under UV irradiation. The effect of C20AA loadings on the UV‐curing efficiency and final polymer performance were investigated. Consequently, the tensile strength, Shore D hardness, pencil hardness, gel content, water resistance, and glass‐transition temperature of the UV‐cured coatings were greatly improved upon the addition of C20AA. Impressively, with the incorporation of 40 wt% C20AA, the resultant UV‐cured coating exhibited highest double bond conversion, superior chemical resistance, and good flexibility. Additionally, all of the coatings showed outstanding transparency and good surface microstructures.

Blends of poly(phenylene sulfide) (PPS) and recycled poly(ether ether ketone) (r‐PEEK) were prepared using a twin‐screw extruder. The carbon nanotube (CNT) added to the blends not only improved the compatibility of the two polymers, but also affected the morphology of the immiscible PPS/r‐PEEK blends. R‐PEEK always forms the dispersed phase and PPS the continuous phase in such blends. In the composite, CNT particles were observed in the PPS phase, mostly distributes in the interface between PPS and PEEK. The results show that r‐PEEK improves the impact and tensile strength of PPS, but does not provide nucleation effect on PPS. However, CNT improved the flexural modulus of PPS/r‐PEEK blends and promoted the crystallization of r‐PEEK rather than that of PPS. The prepared PPS/r‐PEEK blends provided larger electrical conductivity than neat polymers. Adding 20 wt % CNT to blend resulted in composite with the minimum volume resistivity, a reduction of four orders of magnitude, compared with that of the neat blend. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42497.