Bin Hao

Low cost carbon fiber aerogel derived from bamboo for the adsorption of oils and organic solvents with excellent performances

This paper reports the preparation of multi-functional carbon fiber (MCF) aerogel by a simple hydrothermal and carbonization process using disposable bamboo chopsticks. The developed material manifested dramatic multi-functionalities, including excellent flexibility under the mechanical compression, efficient capability to separate oily droplets from water, and high adsorption capacity for a variety of oils and organic solvents by up to 129 times of its own weight. Moreover, the MCF aerogel can be recycled for many times by distillation, combustion or squeezing, making the material satisfy the requirements for oil–water separation in practice. Coupled with economical, environmentally benign manufacturing process, sustainability of precursor and versatility of material, the MCF aerogel developed in this study will be a promising candidate to address the problems arising from the spills of oily compounds.

Ternary silicone sponge with enhanced mechanical properties for oil–water separation

Silicone sponges have been developed and applied over the years for the separation of oil–water mixtures. However, the materials suffer from a poor mechanical performance under cyclic operations. In this work, we report the preparation of ternary silicone sponges via a facile sol–gel process using methyltrimethoxysilane (MTMS), dimethyldimethoxysilicane (DMDMS) and tetraethylorthosilicate (TEOS) as precursors. Special emphasis is put on illustrating the role of TEOS on the morphology, mechanical and thermal properties of the developed silicone sponge. The results show that the introduction of TEOS into the binary silicone sponge resulted in a higher degree of crosslinking reactions, as verified by the chain-like structures in the sample, and the much enhanced mechanical properties and thermal stability of the material. More importantly, the optimized ternary sponge displayed a stable superhydrophobicity, a high efficiency for separating various organic liquids from water, and an excellent recyclability under cyclic operations. The excellent structural and thermal stability of the optimized sponge make it an ideal candidate to be used in the separation industry and for environmental remediation.

Graphene foam with hierarchical structures for the removal of organic pollutants from water

Porous materials with hierarchical structures are of increasing importance because of their potential application in separation and electronic technology. Herein, three-dimensional graphene foam (GF) was prepared by using polystyrene particles as a sacrificial template and an autoclaved leavening process, and the GF was further processed by carbon dioxide as an activation agent to produce meso- and nano-pores in the foam. The resulting hierarchical graphene foam (HGF) exhibits high porosity, hydrophobicity and excellent thermal stability. Compared to regular GF, due to the integration of hierarchically porous structures, HGF manifests outstanding performance for oil adsorption when applied to separating oil–water mixtures, through a combination of hydrophobicity and capillary action.

Control interfacial properties and tensile strength of glass fibre/PP composites by grafting poly(ethylene glycol) chains on glass fibre surface

To control the interphase properties of glass fibre/PP composites, poly(ethylene glycol) (PEG) chains with different average molar mass (w) were grafted onto the glass fibre surface by treating the fibres with γ-APS, HDI and PEG stepwise. The interfacial adhesion of composites was studied as a function of the w of PEG chain grafted on the glass surface. The contact angle measurement, ATR-FTIR, XPS and AFM analysis for the grafted glass fibres (GFs) proved that the PEG chains were grafted onto the GF surface successfully. The increasing roughness of the GF surface confirms that the lengths of the grafted chains grow as the w of PEG increases. The single fibre strength was measured and the data were analyzed by using the two-parameter Weibull model. The results showed that the grafting of PEG on the GF surface lead to a slightly reduced tensile strength and Weibull modulus. The tensile strength of the unidirectional GF reinforced PP composites was tested from 90° and 0° off-axis. It is found that grafting PEG chains onto the GF surface by this three-stage method is an effective means to improve the interfacial adhesion and transverse and longitudinal tensile properties of GF/PP composites. The results showed that as the w of PEG increased, the interfacial adhesion of the composites improved.