Synthesis and characterization of phenolic resol resin blended with silica sol and PVA

Bottom-Up Film-to-Bulk Assembly Toward Bioinspired Bulk Structural Nanocomposites

Biological materials, although composed of meager minerals and biopolymers, often exhibit amazing mechanical properties far beyond their components due to hierarchically ordered structures. Understanding their structure-properties relationships and replicating them into artificial materials would boost the development of bulk structural nanocomposites. Layered microstructure widely exists in biological materials, serving as the fundamental structure in nanosheet-based nacres and nanofiber-based Bouligand tissues, and implying superior mechanical properties. High-efficient and scalable fabrication of bioinspired bulk structural nanocomposites with precise layered microstructure is therefore important yet remains difficult. Here, one straightforward bottom-up film-to-bulk assembly strategy is focused for fabricating bioinspired layered bulk structural nanocomposites. The bottom-up assembly strategy inherently offers a methodology for precise construction of bioinspired layered microstructure in bulk form, availability for fabrication of bioinspired bulk structural nanocomposites with large sizes and complex shapes, possibility for design of multiscale interfaces, feasibility for manipulation of diverse heterogeneities. Not limited to discussing what has been achieved by using the current bottom-up film-to-bulk assembly strategy, it is also envisioned how to promote such an assembly strategy to better benefit the development of bioinspired bulk structural nanocomposites. Compared to other assembly strategies, the highlighted strategy provides great opportunities for creating bioinspired bulk structural nanocomposites on demand.

Preparation, characterization and thermal properties of titanium- and silicon-modified novolac resins

Titanium- and silicon-modified novolac (TSN) resins were prepared by the reaction of novolac resin with the organotitanium polysiloxane. TSN resins with a series of inorganic element contents were prepared, and the corresponding silicon fiber reinforced TSN composites (TSN/silica fiber) were fabricated by the compression molding procedure. The results of thermogravimetric analysis show that the thermal stability of TSN resins were improved by the introduction of inorganic element, both for the initial decomposition temperature and char yields. As the inorganic element increase, the thermal stability also increases initially and then subsequently decreases. Meanwhile, the storage modulus and glass transition temperature ( Tg) of TSN resin composites were improved. TSN-3.12 composite shows the best thermal stability with Tg at 290°C, which was 37°C higher than that of the neat resin composite.