Publications

Sodium humate (SH), a cost-effective and environmentally friendly humic substance, was employed to noncovalently functionalize graphene. The functionalized graphene (SHG) could stably and individually be dispersed in water at very high concentration (up to 30 mg/mL). The stabilization mechanism of SHG colloid was revealed to be π–π interaction and hydrogen bonding between SH and graphene layer. SHG was incorporated into carboxylated nitrile rubber (XNBR) through latex co-coagulation to form XNBR/SHG composites. The composites were cured with sulfur and magnesium oxide (MgO). A unique reinforcement effect of SHG toward XNBR was found. For instance, with the incorporation of 1 phr SHG, the fracture energy of the composite was doubled and the extensibility was improved, while the modulus was practically unchanged. The unique combination of high fracture energy, high extensibility, and low modulus was correlated with the interactions between SHG and MgO which pronouncedly affected the cross-linking of the rubber.

Ni 5 P 4 @FeV LDH exhibits enhanced electrocatalytic activities for the OER (1.50 V at 50 mA cm −2 ) and the UOR (1.44 V at 50 mA cm −2 ). This work provides a new strategy to explore effective OER and UOR electrocatalysts.

Abstract Polylactic acid (PLA)/thermoplastic polyamide elastomer (TPAE) blends were prepared by melt‐compounding on a two‐roll mill. The effects of the TPAE content on the mechanical properties, thermal stability, and rheological behaviors of the blends were fully investigated. With the incorporation of 30 wt% TPAE, the elongation at break and impact strength of the PLA/TPAE blend were increased by 34 times and 3.5 times as compared with the neat PLA, respectively. The improved toughness and tensile ductility were contributed to by the stress whitening and shear plastic deformation, which can absorb energy when subjected to external work. The thermal stability of the PLA/TPAE blends was slightly decreased with the incorporation of the TPA. The dynamic mechanical analysis showed that the blends possessed better elasticity and toughness at low temperatures, and the presence of the TPAE promoted the cold crystallization of the PLA. The rheological behaviors demonstrated that TPAE was compatible with PLA, and obvious chain entanglement occurred between them, resulting in a heterogeneous structure with fine phase separation. Highlights TPAE ensured the overall biodegradability of the toughened PLA. TPAE enhanced the elongation at break and impact strength of the PLA blend. The toughening mechanism and rheological properties were investigated.

The intimate relationship of electrochemical sensors with high sensitivity and reliability has stimulated intensive research on developing versatile materials with excellent electrocatalytic activity.

A graphene material with liquid-like behavior has been synthesized by decorating graphene in a generic, non-covalent fashion and subsequently combining the modified material with bulky polymer chains. The independently dispersed graphene core was first prepared through the chemical reduction of graphene oxide using a fluorescent whitening agent, VBL, as a non-covalent modifier. The negative groups of VBL, which are anchored onto the graphene sheets, impart anionic characteristics to graphene. The combination of the modified graphene with bulky Jeffamine M2070 chains through an electrostatic interaction yields a homogeneous graphene fluid, i.e., graphene-based nanoparticle ionic materials (G-NIMs). The microstructures of G-NIMs were characterized. G-NIMs can be stably dispersed in a broad spectrum of solvents with a super-high concentration of 500 mg mL−1. The intriguing properties of the graphene core and fluidity properties of G-NIMs may offer new scientific and technological opportunities for the applications of graphene.

The energy loss of tires during service is closely related to the hysteresis of tire tread, which is governed by the dispersion and interface of the elastomer nanocomposites. However, traditional undeformable spherical fillers have approached a bottleneck in regulating the viscoelasticity and lowering the hysteresis loss. Herein, the designed covalent interface in the graphene/elastomer nanocomposite maximizes the reinforcement of the nanomaterial as well as minimizes the dynamic energy loss. The reinforced interfacial interaction, an ultralow percolation threshold of tensile strength and high reinforcement synergistically benefit these nano-organized rubber nanocomposites. The energy losses under dynamic loading are largely suppressed in this material, due to the reduced nano-scale frictions. The developed graphene/elastomer nanocomposites are applied to typical dynamic rubber product - auto tires, and the tests indicate that these tires possess energy efficiency close to the highest “A-grade”, which gave great economic and environmental improvements. The critical role of interface structure in the performance of the elastomer nanocomposites was revealed and new design strategy for low dynamic energy losses in rubber products was suggested.

In order to simulate the effect of non-rubber components on strain-induced crystallization (SIC) in natural rubber (NR), sacrificial metal-ligand bonds are incorporated, for the first time, into cis-1,4 polyisoprene cured by sulfur. The incorporation of sacrificial bonds is found to bring in much smaller onset strain for SIC and higher crystallinity compared with the cis-1,4 polyisoprene with sulfide crosslinks only. Accordingly, the striking improvements in tensile modulus and fracture toughness are achieved. The present work contributes to significant insights for mimicking NR outstanding properties in synthesized cis-1,4 polyisoprene and affords new technological route in improving the mechanical properties of synthesized polyisoprene alternative to the nanofilling.

The acceleration of industrialization and motorization has caused increasing consumption of fossil fuels and more greenhouse gas emissions, therefore, greener and renewable alternatives are highly in demand in modern society. Renewable energy can be generated by conversion of solar energy and CO2 through the photosynthesis of plants, forming a theoretical CO2 zero emission cycle. Using biomass resources to extract and produce bio-based fuel chemicals is a renewable strategy moving forward. The use of bio-based chemicals to make bio-based plastics has been actively studied. In this chapter, we will mainly introduce the development of environmentally-friendly bio-based elastomers and their applications in the rubber industry.

In the face of changing outdoor environments, it is necessary for us to develop advanced textiles with thermal regulation and hydrophobic properties. In order to create a fabric with both temperature control and waterproof properties, the study adjusted the ratio of polystyrene (PS) and polyvinylidene fluoride (PVDF) to produce nanofiber membranes with excellent morphology and dirt resistant properties. Furthermore, the hydrophobicity of the nanofibers was further improved by adding SiO 2 to the spinning solution. Based on this, a core solution of octadecane (Oct) was used to give it thermal regulation functionality through coaxial electrospinning technique. The resulting composite nanofiber membrane exhibited excellent hydrophobicity and thermal regulation performance. The measurement results obtained from Differential Scanning Calorimetry (DSC) indicate that the maximum Oct encapsulation rate of the PS/PVDF/SiO 2 @Oct nanofiber membrane is 58.36%. The latent heat of the composite nanofiber membrane is 148.84 J/g, and the water contact angle (WCA) is 135°. The multifunctional composite nanofiber has great potential for applications in outdoor protective clothing and outdoor electronic device protection.

A facile and easily industrialized approach for preparing highly dispersed MMT/polymer nanocomposites is developed by combining the latex compounding method and a spray‐drying process. Clay particles are successfully delaminated into layers, and layer re‐stacking is effectively prevented. HR‐TEM and XRD results confirm that MMT layers achieve exfoliated or nearly exfoliated dispersion in both MMT/styrene‐butadiene rubber and MMT/PS nanocomposites. Compared with melt‐blended MMT/SBR composites, MMT/SBR nanocomposites prepared by this new strategy exhibit extremely high dynamic modulus. magnified image

Many reported polymer/graphene composites, even some with excellent graphene dispersion, do not possess impressive conductivity, which may be due to the failure in forming interconnected conductive paths. In this work, a kind of bio-based polyester (BE) is synthesized by polycondensation between plant-derived diols and diacids. It is then grafted onto graphene oxide (GO) via the easterification between hydroxyls of BE and carboxyls of GO. Subsequently, the grafted GO is subjected to reduce by vitamin C. Because of the presence of terminal hydroxyl group in both ends of the BE chains and multiple carboxyl groups on GO, the grafts form specific spatial interconnection structure in BE matrix. The resulting BE/graphene composites possess impressive low threshold percolation of electrical conductivity, in combination of high thermal conductivity.

A branch relaxation mode was identified for the first time, which provides new implications for natural networking structures in natural rubber.