E-POLYMERS
·
2024
·Vol. 24
·期 1
·
IF 3.2
Mingdong Lei,Ziyou Li,Qiang Gan,Weizhen Zhou,Qiang Li
A series of high temperature vulcanization (HTV) silicone rubbers with TiO 2 ultraviolet (UV) shielding layer and polytetrafluoroethylene (PTFE) hydrophobic layer were prepared via stepwise spray method. It was found that the hydrophobic PTFE liquid emulsion (PTFE L ) could steadily and tightly adhere to the HTV silicone rubber surface by spray method after pre-mixing with permanent room temperature vulcanized (PRTV) silicone rubber during the first step spray. And the subsequent introduction of TiO 2 and PTEF solid powder (PTFE S ) could improve the UV shielding ability and further increase the hydrophobicity of HTV silicone rubber during the second step spray after pre-blending. The accelerated hygrothermal aging process and UV aging process were used to analyze the effect of coating structure and composition on anti-aging performance. And the results indicated that the HTV silicone rubber with PRTV-PTFE L /TiO 2 -PTFE S composite coating showed a favorable UV shielding ability and also possessed an excellent hydrophobicity due to the introduction of low surface energy matter and the building of coarse micro-nano hydrophobic structure. After the aging process, the cracked micro-surface, increased water absorption and decreased mechanical property were displayed for the neat HTV silicone rubber, and these aging phenomena got dramatically improved for PRTV-PTFE L /TiO 2 -PTFE S coating HTV silicone rubber.
Graphical abstract
High temperature vulcanization silicone rubber with hydrophobic–uvioresistant composite coating built by stepwise spray method showed a micro-nano structure and displayed the favorable hydrophobicity and ultraviolet shielding capability.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
CANADIAN JOURNAL OF CHEMICAL ENGINEERING
·
2016
·Vol. 94
·期 12
·2276-2281
·
IF 1.066
Dongjing Liu,Weiguo Zhou,Jiang Wu
The high-temperature H 2 S removal at 500–700 °C was conducted over CuO-CeO 2 /ZSM-5 composites prepared with sol-gel method. 7Cu3Ce/ZSM-5 partially reacting at 500 °C yielded Cu 7 S 4 and Cu 2 S. The major sulphidation products at 600 °C were Ce 2 O 2 S, Cu 2 S, CuS, and S. Sulphidation of 7Cu3Ce/ZSM-5 at 700 °C yielded Ce 2 S 3 , Cu 2 S, Cu 2 S, and S. Sulphidation of 7Cu3Ce/ZSM-5 with 20 % H 2 and 20 % CO generated the same products Ce 2 O 2 S, Cu 2 S, Cu 2 S, and S. Increase in the degree of crystallinity of 7Cu3Ce/ZSM-5 resulted in the decrease of sulphur capacity during the sulphidation and regeneration process. Experimental results showed that the activity of CuO improved by adding Ce; 7Cu3Ce/ZSM-5 performed the optimal sulphiation behaviour at 600 °C with sulphur capacity of 1429 μmol/g (micromoles of sulphur per gram) due to the synergy of CuO and CeO 2 . H 2 repressed sulphur removal, causing the reduction of sulphur capacity from 1429 to 1014 μmol/g. CO had little impact on sulphidation reaction; sulphur capacity only reduced from 1429 to 1221 μmol/g due to the presence of 20 % CO.
研究领域:
环境催化
·
能源化学工程
·
材料科学
·
无机化学
·
气体净化技术
✓ 已验证
DOI
高影响因子
IONICS
·
2024
·Vol. 30
·期 3
·1723-1733
·
IF 2.4
Zhao Ji-wei,Wei Zhi-qiang,Wang Can,Zhou Mei-pan,Lu Cheng-gong
The Co-based organic skeleton was combined with graphene oxide (GO) as a precursor, Ni 2+ hydrolysis etching was introduced, and finally, NiCo-LDH/GO was obtained. The final composite electrode material NiCo 2 S 4 /rGO was obtained by high-temperature vulcanization. The introduction of MOFs and rGO significantly increased the specific surface area of the material and made it have excellent electrochemical properties. The specific capacitance of the composite NiCo 2 S 4 /20rGO reaches an astonishing 272.5 mAh g −1 when the current density is 1 A g −1 . In addition, at a large current of 10 A g −1 , the specific capacitance of the material can also reach 139.5 mAh g −1 , and after a long cycle of 5000 cycles at such a current density, the capacity remains at the original 73.2%. With NiCo 2 S 4 /20rGO electrode material as the positive electrode and activated carbon as the negative electrode, the hybrid supercapacitor is assembled. At an energy density of 56.9 Wh kg −1 , its power density reaches an excellent 799 W kg −1 , and it still has a capacity retention rate of 74% at a current density of 10 A g −1 . The excellent properties of composites demonstrated in this work open up new possibilities for high-quality energy storage devices.
研究领域:
材料科学
·
电化学
·
储能
·
纳米技术
·
无机化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Wei Zheng,Zequn Yang,Jiefeng Chen,Mingguang Zhang,Hongxiao Zu,Ruiyang Qin,Wenqi Qu,Jianping Yang,Lijian Leng,Hailong Li
Utilization of monolithic mineral sulfide-based sorbent for the fix-bed elemental mercury (Hg 0 ) removal is regarded as a predominant predicament in the field of Hg 0 abatement. In this work, a general and facile route was exploited to establish CuS particles decorated 3D porous Ti 3 C 2 T x MXene aerogel via divalent Cu 2+ cations induced assembly combined with subsequent high-temperature sulfurization treatment, during which, uniform CuS particles were homogeneously anchored throughout the Ti 3 C 2 T x substrate. The obtained 3D CuS/Ti 3 C 2 T x MXene aerogel exhibited satisfactory textural property, hierarchical pore structure and strong interaction between Ti 3 C 2 T x MXene and CuS. Meanwhile, the inherent restacking of Ti 3 C 2 T x MXene nanosheet and serious agglomeration of CuS can also be effectively avoided in the formation of aerogel. Those structural advantages originating from this novel gelation process favorably contributes to satisfactory Hg 0 mass transfer and sufficient utilization of CuS active ligands, which largely strengthens Hg 0 removal performance and broadens the fix-bed application of mineral sulfides. Consequently, the Hg 0 capture capacity and adsorption rate of CuS/Ti 3 C 2 T x MXene aerogel reached 90596.4 g m −3 and 120.64 g m −3 min −1 , respectively, far outbalancing those of the reported in-situ selenized copper foam with excellent Hg 0 removal activity. The impressive Hg 0 sequestration performance is attributed to its relatively large specific surface area, layered pore channel, and highly dispersed CuS particles, largely boosting Hg 0 mass transfer and following sequestration. Moreover, other mineral sulfides/Ti 3 C 2 T x MXene aerogels can also be constructed by just replacing divalent metal cations, which makes the initial effort towards the fix-bed utilization of mineral sulfides-based aerogel for vapor-phase Hg 0 immobilization.
研究领域:
环境科学
·
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
ENGINEERING FAILURE ANALYSIS
·
2020
·
IF 2.897
Basharat Mehmood,Mohammad Akbar,Rahmat Ullah
Silicone rubber (SiR) insulators are considered as promising alternatives to conventional ceramic insulators for high voltage transmission networks. However, aging of SiR insulators is an issue when exposed to combined solar, environmental and electrical stresses. In this study, the effect of micro/nano-silica and micro-alumina trihydrate particles on multi-stress aging performance of silicone rubber with DC voltage was investigated. For this purpose, five types of composites were prepared by reinforcing nano-silica (2–6 wt%) and micro-silica/alumina trihydrate (20 wt%) particles into silicone rubber. These composites were exposed to various stresses combining ultraviolet radiations, humidity, heat and electrical in a specially designed test chamber for a duration of 5000 h. For aging assessment, the SiR composites were characterized by visual inspection, and through measurements of hydrophobicity classification, leakage current, scanning electron microscopy, fourier transform infrared spectroscopy and mechanical testing. Results showed that the composite test sample, S-2 (2 wt% nano-silica and 20 wt% micro-silica) exhibited minor surface roughness, highest hydrophobicity and least reduction in contact angle (16.44°). It also measured the lowest leakage current (3.39 μA), maximum tensile strength (3.43 MPa). The hydrophobic ( CH 3 ) and backbone (Si O Si) groups of the test sample, S-2 also remained intact. The composite filled with 2 wt% nano-silica showed maximum resistance to multi-stress aging due to strong molecular interaction between nano-silica and silicone rubber. The outcome of this study will help electric utilities in finding superior alternates of conventional porcelain insulators for high voltage insulation applications.
研究领域:
材料科学
·
电气工程
·
高分子科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）