The article reports the mechanical and thermal properties of graphene oxide (GO)/short carbon fiber (SCF)/polypropylene (PP) composite. The GO‐coated SCF (GO‐SCF) was prepared by a simple physical absorption method. The GO filled PP (GO‐PP) was obtained by extrusion melt‐mixing method. Then, GO‐SCF reinforced GO‐PP composite (GO‐SCF/GO‐PP) was prepared via the conventional extrusion compounding and injection molding techniques. The tensile, flexural and impact strengths of GO‐SCF/GO‐PP were obviously improved due to the chemical reaction and mechanical interlocking between the GO on SCF surface and PP. X‐ray diffraction results showed the GO on SCF surface could act as a β‐nucleating agent for PP crystallization. Differentials scanning calorimeter showed that GO‐SCF/GO‐PP had good thermal stability. Therefore, the multiscale and synergistic effects of GO‐SCF/GO‐PP show the extensive potential on improving mechanical and thermal performance for various fields. POLYM. COMPOS., 39:405–413, 2018. © 2016 Society of Plastics Engineers

There is a constant drive to develop ultra-high-performance multifunctional coatings for existing construction used in modern engineering technologies. For these materials to be used in unsound infrastructure protections, they are required to present enhanced robustness while bearing functionalities to meet multiple uses. Single-function coating is not smart enough to provide satisfactory protection, and the preparation process of multifunctional materials is complex, costly, and provides poor durability. Thus, existing coatings are not suitable to generate an intelligent closed-loop protection system. Herein, we report an innovative 5S multifunctional intelligent coating (5SC) for existing construction materials with superdurable, superhydrophobic, self-monitoring, self-heating, and self-healing properties. The 5SC material showed highly durable superhydrophobic properties as revealed by the main failure tests of building materials including physical friction (abrasion, scratching), 100% tensile strain, photoaging (3000 h of ultraviolet (UV) aging), acid corrosion (concentrated hydrochloric acid and sulfuric acid), and freeze–thaw aging (salty solution). The coated surface was highly sensitive to pressure, with monitoring thresholds from 1 to 30 000 N per 0.01 m2. It showed an early heating rate as high as 6 °C/min while maintaining very good self-monitoring and ice-melting drainage performance to protect the existing structures. This novel composite material is suitable for constructions in extreme areas where corrosion and freeze–thaw damage can occur. This multifunctional material presents a very broad range of applications and development potential in the construction field.

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In this paper, a centrifuge device is proposed to facilitate the intrusion of a low-melting point metal alloy into the pore space of hardened cement paste. X-ray microtomography is combined with metal centrifugation porosimetry (MCP) to quantitatively investigate 3D pore structure. The low-melting-point metal alloy is melted and introduced into pore space in pastes with water cement ratio of 0.5 and 1.0 at a temperature of 65℃. 3D pore structure is quantitatively analyzed by X-ray microtomography after the molten metal alloy has been consolidated. A new threshold value segmentation method for pore space was proposed using conversion coefficient on region of interest (ROI). Porosity and pore size distribution are tested by MCP and compared with the results based on mercury intrusion porosimetry (MIP). The results show that the contrast between pore space and solid phase in the X-ray microtomography device image is improved. The total porosity obtained by MCP was found to be consistent with the results obtained by MIP.