Highly efficient and environmentally friendly microwave-assisted hydrothermal rapid synthesis of ultralong hydroxyapatite nanowires

Ultralong hydroxyapatite nanowires possess many striking advantages such as high biocompatibility, high flexibility, excellent mechanical properties, high thermal stability, and excellent fire resistance, thus, are promising for applications in various fields. However, the highly efficient, low-cost, and environmentally friendly synthesis of ultralong hydroxyapatite nanowires remains a great challenge. Herein, we report a highly efficient, low-cost, environmentally friendly and energy-saving microwave-assisted hydrothermal strategy for the rapid synthesis of ultralong hydroxyapatite nanowires. This method is based on the green chemistry strategy, using water as the only solvent in the absence of organic solvents. Ultralong hydroxyapatite nanowires with diameters of tens of nanometers and lengths of hundreds of micrometers can be prepared in a short period of time (within 20?min), which significantly shortens the synthetic time by about two orders of magnitude compared with the conventional solvothermal method, showing an ultrahigh efficiency and significant energy saving. Moreover, the as-synthesized ultralong hydroxyapatite nanowires are the ideal raw material for the fabrication of the highly flexible and fire-resistant inorganic paper, which is promising for various applications such as fire-resistant paper documents, and flexible electronic products.     

Anisotropic Aerogels with Excellent Mechanical Resilience and Thermal Insulation from Pleurotus eryngii Fungus

Biomass aerogels with superior sustainability, high compressibility, and resilience are highly attractive for diverse technological applications. Anisotropic fungus aerogels derived from natural Pleurotus eryngii with excellent compressibility and resilience are obtained through a facile and environmentally friendly top-down approach. The preserved alignment of polysaccharide fibers inside fungus aerogels leads to remarkable anisotropic mechanical and thermal insulation properties. The cross-links generated via facile chemical modification endow fungus aerogels with excellent compressibility and resilience (deformation recovery rate of ≥96% even when the compression strain is ≥90%). Moreover, via a facile hydrophobic silanization treatment, the elastic aerogels can be endowed with excellent superhydrophobicity and water resistance. It is anticipated that this facile and sustainable strategy will provide technical support for scalable production of fungus-based aerogels with excellent compressibility and resilience, unique thermal anisotropy, and superior renewability. Meanwhile, the newly developed fungus aerogels will have broad applications in durable thermal insulation and acoustic absorption materials.     

溶胶——凝胶工艺在涂料工业中的应用

采用溶胶－凝胶法制备的涂料,其涂膜致密牢固,与金属、塑料、玻璃、木材等有很强的粘结强度,涂膜各项性能优异,此法已在材料保护、表面处理技术方面得到应用。较系统地介绍了在涂料工业中采用溶胶－凝胶工艺的原理、涂料的制备及应用前景。     

高弹性环氧树脂的合成

环氧树脂具有良好的综合力学性能、优异的粘接性,在诸多领域得到了广泛的应用。但是固化后的环氧树脂交联密度高,内应力大,因而质脆、耐疲劳性与抗冲击韧性差,而使其应用受到一定的限制。综述了合成高弹性环氧树脂的理论和方法,并探讨了高弹性环氧树脂的应用前景。     

稀土多功能热稳定剂在PVC中的性能研究

稀土稳定剂具有高效、无毒、价格低廉等优点,是PVC材料加工应用中的一种新型热稳定剂。它具有优异的热稳定性,能改善PVC材料的力学性能、加工性能和抗老化等性能。可代替传统的铅盐、金属皂类和有机锡类等热稳定剂,在PVC中有广阔的应用发展前景。     

活性炭纤维在化工分离中的应用及研究进展

活性碳纤维 (ACF)是一种优于传统粒状活性炭的新型高效吸附材料 ,它具有吸附容量高 ,吸附、脱附速度快 ,低浓度下的吸附性能突出等特点。本文综述了其在化工分离领域如有机和无机废水处理、空气净化、饮用水的净化等方面的应用 ,介绍了ACF的理论研究进展 ,认为ACF的市场前景广阔     

The reduction of graphene oxide

Graphene has attracted great interest for its excellent mechanical, electrical, thermal and optical properties. It can be produced by micro-mechanical exfoliation of highly ordered pyrolytic graphite, epitaxial growth, chemical vapor deposition, and the reduction of graphene oxide (GO). The first three methods can produce graphene with a relatively perfect structure and excellent properties, while in comparison, GO has two important characteristics: (1) it can be produced using inexpensive graphite as raw material by cost-effective chemical methods with a high yield, and (2) it is highly hydrophilic and can form stable aqueous colloids to facilitate the assembly of macroscopic structures by simple and cheap solution processes, both of which are important to the large-scale uses of graphene. A key topic in the research and applications of GO is the reduction, which partly restores the structure and properties of graphene. Different reduction processes result in different properties of reduced GO (rGO), which in turn affect the final performance of materials or devices composed of rGO. In this contribution, we review the state-of-art status of the reduction of GO on both techniques and mechanisms. The development in this field will speed the applications of graphene.     

Robust Superhydrophobic Fabric for Durability,Self-Cleaning,and Oil/Water Separation via Thiol–Acrylate Polymerization

In recent years, highly efficient oil/water separation materials have brought much attention. It requests superhydrophobic surfaces with a rapid and facile separation process, excellent durability, and large-scale fabrication. Herein, a facile vapor-liquid sol-gel, and free radical polymerization reaction method to prepare the durable and robust superhydrophobic cotton fabric is proposed. Moreover, the fabric can be used for highly efficient and various oil/water separation. It is prepared via a simple two-step process, including a vapor-liquid sol-gel process to deposit with thiols particles, and then followed a free radical polymerization reaction to graft 2,2,3,4,4,4-hexafluorobutyl methacrylate. Scanning electron microscopy and Fourier transform infrared spectrometry prove that the rough structures are generated from the hydrolysis condensation reaction between tetraethyl orthosilicate and 3-mercaptopropyltriethoxysilane. As a result, the synthetic chemical composition provided by the natural fabric and silica nanoparticles synergistically construct a superhydrophobic surface with water contact angles and shedding angle of 158° and 9°, respectively. Additionally, the treated fabric exhibits excellent chemical resistance and self-cleaning ability. Remarkably, the fabric still retains superhydrophobic and excellent mechanical robustness after 30 cycles of various oil/water separation. In summary, the resultant fabrics with excellent chemical resistance, remarkable mechanical robustness, and versatile separation abilities have potential applications in various oil/water separations.     

Durable and highly sensitive flexible sensors for wearable electronic devices with PDMS-MXene/TPU composite films

MXenes, as two-dimensional (2D) transition metal carbides, carbonitrides, and nitrides, have very excellent electrical properties and surface activity and are increasingly used in supercapacitors, batteries, electromagnetic interference shielding, and composite materials. Still, the poor stability of MXene when exposed to aqueous oxygen and the poor ability to interact with the polymer matrix have become important factors limiting its’ practical applications. To enhance stability, highly conductive and stretchable Ti₃C₂MXene/TPU sensing elements were prepared by a simple spraying process using thermoplastic polyurethane (TPU) as a substrate, and the sensing elements were encapsulated by polydimethylsiloxane (PDMS) to obtain MXene-TPU/PDMS constructed flexible strain sensors with excellent performance. This strain sensor features low detection limits (less than 0.005%, 0.5 μm), a wide sensing range (0–90%), a short response time (120.1 ms), and excellent durability (>3000 cycles). This strain sensor can be applied to a range of applications such as health detection, motion signals, detection of robot movements, and wearable electronic devices.     

Mass polymerized PVC in wire and cable applications

Mass (bulk) polymerized PVC is used extensively in rigid extrusion applications on a worldwide scale. However, relatively small quantities are used in flexible products such as wire and cable. This is surprising considering the uniformity of the resin, its highly accessible porosity, and its consistency batch-to-batch. There was concern that mass polymerized PVC would not meet existing specifications. A study was undertaken to determine if mass resin could be used in various wire and cable applications. The results show mass resin compounds may have slightly lower electrical properties but still within specification. Selected physical and aging properties are also satisfactory. Independent testing has confirmed our results. Based on this study, major wire and cable producers are now routinely using mass resin with excellent results.