Radioactive iodine anion wastewater is generated during the operation of nuclear facilities. Efficiently adsorbing and removing radioactive iodine is crucial for the sustainable development of nuclear energy. A potential adsorbent, nano silver-loaded activated carbon fiber (Ag@ACF), was prepared through hydrothermal synthesis and high-temperature vacuum reduction for the efficient removal of iodide anions. The as-prepared Ag@ACF composite has been comprehensively characterized, with silver nanoparticles uniformly distributed on the surface and pore walls of the Ag@ACF, enhancing the adsorption sites for iodine anions. The adsorption performance of Ag@ACF towards iodine anions was evaluated through column and batch experiments, varying silver concentration, adsorbent dosage, pH, contact time, and competing anions. Ag@ACF demonstrated high water stability and a low desorption rate of iodine anions. At a pH of 2, Ag@ACF exhibited a maximum adsorption capacity for iodine anions of 372 mg/g, surpassing most other adsorbents and showing promise for engineering applications. Adsorption kinetics and isotherm analysis indicated that the adsorption process of Ag@ACF primarily involved monolayer homogeneous chemisorption, resulting in the formation of stable AgI. These results suggest that Ag@ACF could serve as a potential adsorbent for removing iodine from radioactive wastewater.

Film/substrate systems with periodic surface morphology generated by elastic instability can have important applications in elastic wave control, as proved by previous finite element analysis. However, experimental verification remains a challenge because of the limited magnitude and adjustment of patterns wavelength, the interface debonding and the structure warpage. A novel experimental method in which film and substrate are selected homologues, and two-phase moisture curing process is adopted to control the physical state of the substrate, the surface pattern and the residual mismatch stress was firstly proposed to prepare the bilayer structures without the detachment and the warpage. Vibration test showed that propagation of the elastic waves could be suppressed in the fabricated bilayer system. Through modelling the formation of surface patterns and the propagation of elastic waves, finite element simulation and dimensional analysis were carried out to examine the band-gap performance of various bilayer structures. Numerical results show that the wavelength of surface patterns which depends on four processing parameters, i.e., the instability load, the film thickness and the elastic moduli of the film and the substrate after the first curing, is crucial to the band-gap properties of film/substrate systems. An analytical expression is given to approximately estimate the surface patterns wavelength and a design guide is suggested to manufacture the film/substrate system considering the film limiting conditions in practice.

Soft materials such as biological tissues are prone to deformation and generate different stable structures under external stimulation. This property is widely used to create tunable patterns, and the tuning of the wrinkling patterns can be applied to the control of elastic waves. In this paper, the wrinkling modes of film/substrate systems with different geometric dimensions and material parameters were studied. It is verified by numerical simulation that the elastic wave band gaps corresponding to the two wrinkling modes can be effectively superposed in one system, and the experimental samples with two wrinkling modes coexisting in one system were prepared by parameter optimization and a moisture-curing process. A vibration test showed that the hybrid system could effectively suppress the propagation of elastic waves. Combined with engineering needs, the wrinkling system under different loading conditions was studied, which provides a design guide for widening and regulating the elastic wave band gap.

以碳纳米管(CNT)作为核,密胺树脂(MF)作为壳,苯乙烯马来酸酐共聚物(SMA)为乳化剂,原位聚合制备微胶囊化碳纳米管(CNT-MF),并将包覆后的碳纳米管作为填料添加到硅橡胶泡沫中,制备了CNT-MF/硅橡胶泡沫复合材料.探讨了核/壳质量比对微胶囊化碳纳米管的包覆效果的影响,同时研究了微胶囊化碳纳米管用量对硅橡胶泡沫泡孔结构和介电性能的影响.结果 表明,微胶囊化碳纳米管的加入有利于提高复合材料的泡孔结构,大泡孔的存在和泡孔面积有利于材料介电性能的提高.当核/壳质量比为1∶10的微胶囊化碳纳米管添加量为15 phr时,复合材料介电性能表现最佳,此时复合材料在1 kHz的介电常数为26.34,介电损耗仅为0.0136.

主要研究包覆碳纳米管对环氧树脂介电性能的影响.三聚氰胺甲醛树脂原位聚合对碳纳米管进行包覆,在碳纳米管表面形成高分子绝缘层使其在填充过程中不易相互导通.将包覆碳纳米管按不同包覆比加入环氧树脂,制备环氧树脂/包覆碳纳米管复合材料.当包覆碳纳米管与环氧树脂的包覆比为1∶10,制得的复合材料在1kHz时介电常数为117,是纯环氧树脂的16.7倍,但介电损耗为0.052,较纯环氧树脂增加了44.4％.

研究了红磷与壁材(三聚氰胺甲醛树脂)的质量比例、反应时间、反应温度对包覆红磷性能的影响.采用扫描电镜、热重分析仪、激光粒度仪对包覆前和包覆后红磷粒子进行了测试表征.结果发现,红磷与壁材的质量比为8:7、反应温度设定为65℃、反应时间为2.5 h,可以获得包覆性能良好的红磷.

以苯乙烯马来酸酐共聚物(SMA)为乳化剂、三聚氰胺甲醛树脂(密胺树脂,MF)为壁材、片状石墨烯(GE)为芯材,通过原位聚合法制备了包覆的石墨烯"微胶囊",并以微胶囊作为填料,双组分室温硫化泡沫硅橡胶(RTVSR)作为基体,通过室温硫化(RTV)硅橡胶制备具有泡孔结构的电介质复合材料.提出了对石墨烯进行微胶囊化包覆的制备新工艺,讨论了超声分散功率、石墨烯与壁材的用量比例对微胶囊形貌和包覆效果的影响,并比较了包覆前后、发泡前后电介质复合材料的介电性能.研究结果表明,石墨烯与壁材质量比为1∶100、超声功率为840 W时制备的分散液较稳定、石墨烯的表面附着物较多;同时包覆(微胶囊化)能减少石墨烯发生团聚,0.3g微胶囊填量下,包覆后的微胶囊石墨烯/泡沫电介质材料的介电常数是包覆前石墨烯/硅橡胶电介质材料的2.45倍,而介电损耗比石墨烯/硅橡胶复合材料还低,只有0.002,同时泡孔的存在有利于提升复合材料的介电性能.

通过室温硫化(RTV)法制备了不同泡孔直径的石墨烯/有机硅橡胶泡沫复合材料.提出了一种制备不同发泡倍数的双组分室温硫化加成型有机硅橡胶泡沫复合材料的工艺;讨论了石墨烯含量、发泡倍数、泡孔的数目和尺寸对室温硫化硅橡胶泡沫介电性能的影响.结果 表明,在同一发泡倍数下,介电常数随石墨烯的添加量增加而增加,达到阈值后降低;在同一石墨烯添加量下,泡孔尺寸和泡孔数目有着不同贡献:直径、泡孔数目较少时,介电常数降低,泡孔的总数和大孔的占比较多时,介电性能最佳.此外含有石墨烯的有机硅橡胶泡沫复合材料较纯硅橡胶泡沫而言,其介电常数提升了6倍左右,同时保持着较低的介电损耗.

为了提高红磷阻燃剂的稳定性,通过原位聚合方法制备三聚氰胺甲醛树脂包覆红磷.通过扫描电镜、马尔文激光粒度仪、pH测试、热重分析仪对包覆前后红磷颗粒进行表征.扫描电镜和马尔文激光粒度仪结果表明,三聚氰胺甲醛树脂可以很好地对红磷颗粒进行包覆.pH值测试显示,与未包覆红磷相比,包覆后的红磷在水下储存稳定性明显提高.热重分析结果说明,包覆红磷可以有效提高红磷的热稳定性,与未包覆红磷相比,包覆红磷的分解温度提高约57℃.同时研究了红磷粒径对包覆红磷性能的影响,包覆红磷随着红磷粒径的降低,热稳定性降低.

环氧树脂和硅橡胶因其优异的性能在功能材料制备方面有着广泛的应用,常作为黏结剂用于超疏水涂层的制备.采用不同比例的疏水二氧化硅纳米粒子、环氧树脂和硅橡胶的甲苯溶液,通过简单的喷涂成膜法制备了具有不同疏水性的疏水涂层.结果 表明,当二氧化硅的质量分数为25％时,所制备的涂层展现出优良的超疏水性能,与水的接触角为157.50°,同时所制备的超疏水涂层表现出良好的自清洁性和耐磨性.