With a high melting temperature and good crystallization ability, poly­(neopentyl glycol 2,5-furandicarboxylate) (PNF), a polyester derived from bio-based 2,5-furandicarboxylic acid and neopentyl glycol, has been proposed and proved to be a promising hard segment for the development of novel bio-based thermoplastic poly­(ether-ester) elastomer (TPEE). The resulting TPEE, namely PNF–PTMG, has high performance comparable to the petroleum-based counterpart PBT–PTMG (i.e., Hytrel, Dupont). Among all of the existing polyesters derived from bio-based 2,5-furandicarboxylic acid (FDCA), PNF has perfectly balanced properties, namely, a high melting temperature of 200 °C and a good crystallization ability to easily grow medium to large-size crystalline spherulites. Characterizations based on dynamic mechanical analysis and small-angle X-ray scattering suggest that there are two domains in PNF–PTMG, the crystalline PNF and a mixture of amorphous PNF and PTMG. These two domains form microphase separation induced mainly by the crystallization of PNF. By adjusting the PTMG soft segment from 30 to 60 wt%, PNF–PTMG shows a melting temperature, tensile modulus (E), and elongation at the break (εb) ranging from 180 to 134 °C, 738 to 56 MPa, and 38 to 1089%, respectively. More importantly, the shape recovery ratios increase from 57 to 90% at 200% strain when the amount of PTMG increases from 50 to 70 wt%, indicating excellent elastic property. These results indicate that PNF is an excellent hard segment to serve as a strong physical cross-link so that PNF–PTMG is able to display high performance comparable to extensively commercialized PBT–PTMG.

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Breakdown failure in insulation material is one of the key problems that threaten the safe operation of high-voltage direct current cable. In this work, the effect of boron nitride nanosheets (BNNSs) concentration, space charge and temperature on DC breakdown strength have been explored. Cross-linked polyethylene (XLPE)/BNNS nanocomposites were prepared by the melt blending method, and the basic characteristics of nanoparticles and composite were characterised. The experimental results indicate that DC breakdown strength of nanocomposite can be effectively improved when a small amount of BN nanosheet is doped into the matrix. The breakdown strength of the sample reaches the maximum value of 407.52 kV/mm when BNNS content is 0.5 wt%, which is about 33% higher than that of pure XLPE. Further, the effect of space charge on the breakdown of nanocomposites has been studied by pre-injecting charges. For the samples with different BNNS contents, all the breakdown strength present ascending trend when the polarity of the applied voltage is the same as that of the pre-injected charges. Besides, it can be found that the breakdown strength of the XLPE/BNNSs composite decreases significantly at 50°C, which is due to more charge accumulation at 50°C. It reaches 2.06 × 10 −8 C which increases by about 2.2 times than the room temperature.

As an indispensable part of high-voltage direct current (HVDC) cable, the semiconductive shielding layer plays the role of uniforming electric field in the cable. However, cable shielding materials >35 kV mainly rely on foreign imports in China, which belongs to the technical weak issues in the field of electrical materials. At present, there are few systematic reports on semiconductive shielding material of HVDC cable. In the work, the mechanisms of charge conduction and thermal conduction of semiconductive material have been introduced. Effect of raw material, carbon black content and the second conductive filler on the resistance characteristics of the semiconductive layer, the charge accumulation characteristics of the insulating layer and the interface characteristics have been studied. A kind of semiconductive layer as a high voltage terminal charge emission method has been proposed to study charge emission from the semiconducting layer to the insulation layer. This work can provide theoretical guidance for the research of semiconductive shielding materials.

Compared with the monometallic phosphides, bimetallic phosphides can further improve the catalytic performance for hydrogen evolution reaction (HER). As such, the rational design and facile synthesis of bimetallicbased phosphides with well-controlled architectures and compositions is of scientific and technological importance. In this work, Fe−Co Prussian blue analogue (PBA) nanocones (NCs) have been successfully fabricated via an intercalation reaction strategy by utilizing layer structured α-Co(OH) 2 NCs as self-sacrificing templates. After calcination and phosphorization process, Fe−Co PBA NCs can be converted to Fe-doped Co x P NCs without obvious shrinkage. Electrochemical tests show that Fe incorporation can effectively promote the electrocatalytic activities of Co x P. This simple and effective method will be of benefit for the development of other functional Co-based bimetallic compounds. Furthermore, this strategy can possibly be extended to fabricate a series of PBA materials with special structure and novel morphology, which can serve as a promising platform for diverse applications, especially in energy storage and conversion.

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