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Biodegradable polymer/bioceramic composites scaffold can overcome the limitation of conventional ceramic bone substitutes such as brittleness and difficulty in shaping. To better mimic the mineral component and the microstructure of natural bone, novel nano-hydroxyapatite (NHA)/polymer composite scaffolds with high porosity and well-controlled pore architectures as well as high exposure of the bioactive ceramics to the scaffold surface is developed for efficient bone tissue engineering. In this article, regular and highly interconnected porous poly(lactide-co-glycolide) (PLGA)/NHA scaffolds are fabricated by thermally induced phase separation technique. The effects of solvent composition, polymer concentration, coarsening temperature, and coarsening time as well as NHA content on the micro-morphology, mechanical properties of the PLGA/NHA scaffolds are investigated. The results show that pore size of the PLGA/NHA scaffolds decrease with the increase of PLGA concentration and NHA content. The introduction of NHA greatly increase the mechanical properties and water absorption ability which greatly increase with the increase of NHA content. Mesenchymal stem cells are seeded and cultured in *Author to whom correspondence should be addressed. E-mail: renjie@mail.tongji.edu.cn three-dimensional (3D) PLGA/NHA scaffolds to fabricate in vitro tissue engineering bone, which is investigated by adhesion rate, cell morphology, cell numbers, and alkaline phosphatase assay. The results display that the PLGA/NHA scaffolds exhibit significantly higher cell growth, alkaline phosphatase activity than PLGA scaffolds, especially the PLGA/NHA scaffolds with 10 wt.% NHA. The results suggest that the newly developed PLGA/NHA composite scaffolds may serve as an excellent 3D substrate for cell attachment and migration in bone tissue engineering.

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In this study, a novel fluorinated polybenzoxazine (PBZ) is successfully designed for the first time to fabricate superhydrophobic films on a glass surface. 2,2-Bis(3-fluorophenyl-3,4-dihydro-2H-1,3benzoxazinyl)hexafluoro propane (BAF-fa) is successfully synthesized utilizing a conventional onepot Mannich reaction. The transformation of the polymeric film of BAF-fa from hydrophobic to superhydrophobic has been achieved with silica modification, thus showing the involvement of the phenomena of low surface free energy and surface roughness combined. The method to fabricate uniform hybrid films resulted in a water contact angle (WCA) of 163u, and possesses the advantages of being straightforward and inexpensive. Morphological studies have revealed the induced hierarchical roughness of the hybrid films over multiple scales. The as-prepared hybrid films are superhydrophobic not only for neutral water, but also for water with a wide pH range. Additionally, these hybrid superhydrophobic films have shown promising durability in tap water and ethanol at different temperatures. This finding provides an effortless method to fabricate sliding superhydrophobic surfaces with high durability, thus expanding the role of PBZ in super waterrepellency.