基于2,4-二羟基苯甲酸铜(Ⅱ)为载体的硫氰酸根电极的电位响应

制备了基于一种简单的金属铜配合物2,4-二羟基苯甲酸铜(Ⅱ)(Cu(Ⅱ)DHBA)为载体的PVC膜硫氰酸根离子(SCN-)选择性电极。该电极在1.0×10-1～1.0×10-6mol/LSCN-浓度范围内呈现斜率为-59.5mV/dec的近Nernst电位响应,检测下限为9.1×10-7mol/L。利用紫外可见光谱及交流阻抗技术初步探讨了电极对SCN-呈现的选择性电位响应机理。该电极作为直接电位分析法的指示电极,成功运用于实验室废水中硫氰酸盐含量的测定。     

Improving antibacterial,biocompatible, and reusable properties of polyvinyl chloride via the addition of aluminum alkoxides

Global bacterial infections associated with conventional polyvinyl chloride (PVC) medical devices place a heavy burden on healthcare systems and thus it will be desirable if medical devices are made from antimicrobial PVC. There are numerous studies focusing on polymer surface modifications to either leach antimicrobial agents or kill pathogenic microbes upon direct contact. In this work, mannitol fumarate ester-based aluminum metal alkoxide (MFE-Al) additive was developed to confer simultaneously improved antibacterial property and enhanced high temperature sterilization resistance of the resultant PVC. Data obtained confirm that the MFE-Al stabilized PVC sheets significantly inhibit 98% bacterial growth. They also show biocompatibility with cultured H9C2 cardiomyocytes and hemocompatibility in vitro. Dry heat sterilization is generally not suitable for PVC medical wares due to their poor thermal compatibility. Surprisingly, our antimicrobial-biocompatible PVC can maintain stability at 180°C for 90 min. Such a high thermal stability indicates the MFE-Al stabilized PVC can endure 90 cycles of dry-heat sterilization without significant damage. This study may provide a solution to reduce PVC medical waste for a maximum benefit without compromising human health or the environment.     

化学气相沉积法制备碳化铬薄膜的研究

以三（2,2,6,6-四甲基-3,5-庚二酮）化铬为前驱体,采用化学气相沉积（CVD）法在氧化铝（Al₂O₃）陶瓷基板上制备碳化铬（Cr₃C₂）薄膜,其中沉积温度为723 K至923 K,沉积时间为1 200 s。研究了不同沉积温度对Cr₃C₂薄膜的相组成、择优取向、宏观表面、微观结构及电学性能的影响。结果表明,在723 K至923 K下制备得到具有高度（130）择优取向的Cr₃C₂薄膜。随着沉积温度的升高,Cr₃C₂薄膜表面先由光滑变粗糙,后逐渐变光滑;薄膜晶粒呈椭球型生长;薄膜的厚度先增加后减小,从而导致电阻先减小后增大。在798 K时制备得到厚度最大且电阻最小的（130）择优取向的最佳Cr₃C₂薄膜。同时,在实验条件下Cr₃C₂薄膜表面存在少量的碳和Cr₂O₃。     

多孔结构耐磨超疏水薄膜的制备及性能

为了获得持久稳定的超疏水材料,本研究将聚偏氟乙烯共六氟丙烯共聚物（P(VDF-HFP)）和疏水改性的纳米三氧化二铝（Al2O3）进行复合并通过溶剂/非溶剂诱导相分离法制备了一种耐磨超疏水薄膜。采用SEM及能谱分析仪和接触角测量仪分别对薄膜的表面微观结构、化学组成和疏水性能进行表征。结果表明：制备的薄膜具有自相似微纳米复合微观结构。并且薄膜具有优异的自清洁性和耐机械摩擦性,即使经历360个周期的砂纸磨损（100 g载重）后仍保持超疏水性。除此之外薄膜具有优异耐化学溶液和紫外灯照射稳定性。     

Facile Fabrication of Poly(vinyl alcohol)/Polyquaternium-10 (PVA/PQ-10) Anion Exchange Membrane with Semi-Interpenetrating Network

Anion exchange membranes (AEMs) are one of the core components of AEM fuel cells. A series of poly(vinyl alcohol)/polyquaternium-10 (PVA/PQ-10) AEMs with semi-interpenetrating networks (s-IPNs) are prepared by a simple solution-casting method using glutaraldehyde (GA) as a cross-linking agent. Subsequently, the prepared PVA/PQ-10 cross-linked membranes are characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis, mechanical analysis, water uptake and swelling ratio tests, ion exchange capacity (IEC) tests, ionic conductivity measurements, and oxidative/alkaline stability tests. The effects of the mass ratio of PVA and PQ-10 and the amount of cross-linking agent GA on the performance of the PVA/PQ-10 cross-linked membranes are systematically explored. The results show that the cross-linked PVA/PQ-10 AEMs have high IEC and low water uptake and swelling ratio, and its maximum ionic conductivity can reach 79.37 mS cm^–1 at 80 °C. In addition, the PVA/PQ-10 cross-linked membrane has good oxidative and alkaline stability under optimal preparation conditions. These results may provide valuable insights toward more effective scheme designs and new, simple preparation methods for AEMs with s-IPN structures.     

A Facile Approach toward Thermoplastic Triple-Shape Memory Polymers

In this work, a ternary blend of polyolefin elastomer (POE), lauric acid (LA), and poly(ε-caprolactone) (PCL) with triple-shape memory effect (triple-SME) is reported. LA and PCL exhibit distinct thermal transitions and construct two reversible switching networks capable of fixing and releasing different temporary shapes under a mild condition. The ternary blend shows excellent triple-shape memory properties and good toughness. Besides, the permanent shape can be reconfigured by a simple thermal treatment. These particular features make the novel blend a competitive candidate for diverse applications. And the creative combination of crystalline small molecule and semicrystalline polymer expands the freedom for producing triple-shape memory polymers (triple-SMPs).     

Stereocomplex Crystallization Induced Significant Improvement in Transparency and Stiffness–Toughness Performance of Core-Shell Rubber Nanoparticles Toughened Poly(l-lactide) Blends

Toughening modification of poly(l -lactide) (PLLA) with rubber particles is often realized at the cost of transparency, mechanical strength, and modulus because high rubber loadings are generally required for toughening. In this work, a promising strategy to simultaneously improve the transparency and stiffness–toughness performance of poly(butyl acrylate)-poly(methyl methacrylate) (BAMMA) core-shell rubber nanoparticles toughened PLLA blends by utilizing the stereocomplex (SC) crystallization between PLLA and poly(d -lactide) (PDLA) is devised. The results reveal that the construction of SC crystallites in PLLA matrix via melt-mixing PLLA/BAMMA blends with PDLA can prevent BAMMA nanoparticles from aggregation and promote them to form network-like structure at lower contents. As a result, not only higher toughening efficiency with less rubber contents but also superior transparency is achieved in the PLLA/PDLA/BAMMA blends as compared with the PLLA/BAMMA ones where large aggregated BAMMA clusters are formed. Moreover, the outstanding reinforcement of SC crystallites network for PLLA can impart an enhanced tensile strength and modulus to PLLA/PDLA/BAMMA blends, thus improving the stiffness–toughness performance of PLLA/PDLA/BAMMA blends to a higher degree. This work demonstrates that SC crystallization is a promising solution to solve the contradiction between transparency and mechanical properties and then obtain superior comprehensive performances in rubber toughened PLLA blends.     

Direct-Ink-Writing of Electroactive Polymers for Sensing and Energy Storage Applications

Considering the high levels of materials used in the fields of electronics and energy storage systems, it is increasingly necessary to take into consideration environmental impact. Thus, it is important to develop devices based on environmentally friendlier materials and/or processes, such as additive manufacturing techniques. In this work, poly(vinylidene fluoride) (PVDF) and poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) are prepared by direct-ink-writing (DIW) by varying solvent evaporation temperature and fill density percentage. Different morphologies for both polymers are obtained, including dense films and porous membranes, as well as different electroactive β-phase content, thermal and mechanical properties. The dielectric constant and piezoelectric d₃₃ coefficient for dense films reaches up to 16 at 1 kHz and 4 pC N⁻¹, respectively for PVDF-HFP with a fill density of 80 and a solvent evaporation temperature of 50 °C. Porous structures are developed for battery separator membranes in lithium-ion batteries, with a highest ionic conductivity value of 3.8 mS cm⁻¹ for the PVDF-HFP sample prepared with a fill density of 100 and a solvent evaporation temperature of 25 °C, the sample showing an excellent cycling performance. It is demonstrated that electroactive films and membranes can be prepared by direct-ink writing suitable for sensors/actuators and energy storage systems.     

3D Printing Conductive Composites with Poly(ionic liquid) as a Noncovalent Intermedia to Fabricate Carbon Circuits

In this study, a kind of imidazole type poly(ionic liquid) ([PEP-MIM]Cl) is synthesized, which can disperse carbon effectively. [PEP-MIM]Cl is used as an intermediate to coat carbon on the poly(acrylic acid)(PAA-co-MBA) via ion exchange to obtain conductive polymer composite (CPC). A series of characterizations are performed. Experiments show that carbon can be coated on the PAA-co-MBA uniformly, and compared with using carbon as filler, this method requires less carbon to achieve good conductive performance. The carbon layer on the polymer's surface is enriched via the swelling-shrinking properties of PAA-co-MBA according to the SEM images. Furthermore, in combination with 3D printing technology, PAA-co-MBA can be designed into different shapes to achieve various functions such as pressure-sensing element. Finally, a new type of CPC named carbon clad polymeric laminate (CCPL) is prepared by using the carbon coating method and 3D printing technology. It has the potential to replace copper clad laminate (CCL) and printed circuit board (PCB), to a certain extent. This technology expands the preparation method and application of the CPC such as flexible and wearable conductive fabrics.