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A hyperbranched polyol (HBP) was synthesized with poly(ethylene glycol) (PEG) as the core molecule and 2,2‐bis(hydroxymethyl) propionic acid as the chain extender. Then, a series of hyperbranched polyurethane phase‐change materials (HP‐PCMs) with different crosslinking densities was synthesized with isophorone diisocyanate and HBP as a molecular skeleton and PEG 6000 as a phase‐change ingredient. 1H‐NMR, gel permeation chromatography, and Fourier transform infrared spectroscopy confirmed the successful synthesis of the HBP and HP‐PCMs. The polarization optical microscopy and wide‐angle X‐ray diffraction results show that the HP‐PCM exhibited good crystallization properties, but the crystallinity was lower than that of PEG 6000. The analysis results from differential scanning calorimetry indicated that the HP‐PCMs were typical solid–solid phase‐change materials with suitable phase‐transition temperatures. In addition, HP‐PCM‐3, with an appropriate degree of hyperbranched structure, possessed the highest thermal transition enthalpy of 123.5 J/g. Moreover, thermal cycling testing and thermogravimetric analysis showed that the HP‐PCMs exhibited good thermal reliability and stability. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45014.

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Based on the starving tumor concept, we first raised an idea that the pH-sensitive Ca2+ release of CaCO3 NPs induced blood coagulation of tumor vessels, and explored the in vitro and in vivo blood coagulation behaviors of CaCO3 NPs by acid stimulus.

To construct waterborne polyurethane with excellent water resistance and mechanical properties, an organic-inorganic hybrid nanocomposite based on modified halloysite nanotubes (mHNTs) and polyurethane was prepared. The HNTs were modified with an amino-silane coupling agent (KH550) and then reacted with polypropylene glycol, 2,2-Dimethylol propionic acid, and Toluene diisocyanate to form mHNTs/PU aqueous dispersions. The structure of the siloxane functionalized mHNTs was confirmed by a Fourier transform infrared study. The PU/mHNTs composites were characterized by using differential scanning calorimetry, scanning electronic microscopy, thermal gravimetric analysis, a tensile test, particle size analysis, and a water swelling experiment. The tensile strength, Young's modulus, and elongation at the break of the composite polymer with 0.5 wt % mHNTs was shown to be significantly improved, by approximately 200%, 200%, and 30%, respectively. An excess amount of mHNTs could weaken the reinforcing effect and stability of the composite emulsion.