Carbon fiber (CF) reinforced polyphenylene sulfide (PPS) composite shows extraordinary thermal stability, chemical resistance, and processability. The interface between CF and PPS transfers the load, and its properties are crucial to determine composite properties such as mechanical performance, reliability, and so forth. This work explores the relationship between surface properties of CFs (with/without sizing layer) and the interfacial properties of CF/PPS composite. X‐ray photoelectron spectroscopy, scanning electron microscopy, atomic force microscope were employed to evaluate surface physicochemical properties of CFs, and reveal the increasing roughness and decreasing content of functional groups on the CF surface after desizing. Inverse gas chromatography and dynamic contact angle tests were adopted to characterize the surface energy of CFs, and present that the dispersive component of surface energy increases, while the polar component decreases, and the total surface energy is barely changed after desizing. Differential scanning calorimetry measurement reveals the increasing crystallinity of CF/PPS after CF desizing. Microbond test was performed to analyze interfacial shear strength (IFSS) of CF/PPS, displays that IFSS keeps almost constant after CF desizing. The results demonstrate that the surface energy of CF is important to the interfacial crystallinity, but not the critical factor for interfacial strength of CF/PPS composite.

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Glazed hollow bead, a kind of inorganic lightweight aggregate that has been recently developed, has raised high concern in the field of thermal insulation of building wall due to its low thermal conductivity, low water absorption, good fireproof performance and relatively high compression strength. In this paper, the preparation of this thermal insulation glazed hollow bead material was introduced in detail, the influence of the amount of gel material on bulk density, porosity, thermal conductivity, compression strength of the thermal insulation glazed hollow bead material was investigated, the surface morphology and surface components were characterized by means of SEM and EDS. Results showed that the density, thermal conductivity and compression strength increased while the porosity decreased with the amount of gel material increasing. Appropriate temperature enables gel material to work at optimal level under which the compression strength increases, on the other hand, the porosity also increases, therefore, the thermal conductivity decreases.

The mechanical properties and durability of concrete with or without ultrafine fly ash were studied by measuring the compressive strength and determining the chloride ion penetration and open porosity of concrete. The results show that the addition of ultrafine fly ash reduces the compressive strength at 1 day and can significantly improve the compressive strength of concrete at later ages. The durability of concrete can be enhanced by the using of ultrafine fly ash and lowering the W/B.

To enhance the durability of the cement concrete of the bridge, C40 and C50 concretes with different raw materials have been made. A method of optimal selection method for raw materials has been put forward. For different raw materials from different plant, based on the orthogonal experimental design, certain raw materials groups are gained. By the same C40 and C50 concrete mix proportion but different raw materials groups, the specimens have been made for testing the performance of the compressive strength, carbonization and anti-chloride penetration. By range analysis, the best raw material group of the concrete with higher compressive strength, lower chloride penetration coefficient and lower carbonization depth has been selected.