JOURNAL OF APPLIED POLYMER SCIENCE
·
2023
·Vol. 140
·期 39
·e54455
·
IF 3
Wenjie Feng,Jiadeng Zhu,Chen Yang,Wentao Li,Mengjin Jiang
Poly-p-phenylene-(1,3,4-oxadiazole) (POD) fibers have attracted tremendous attention due to the excellent thermal stability, however, their poor ultraviolet (UV) resistance seriously restricted the application. Some efforts have been devoted to improving the UV stability of POD, while the methods are generally too complicated or costly. This work applied a simple but effective approach to obtain POD/PPTA composite fibers by blending poly-p-phenylene terephthamide (PPTA) with POD. The results showed that the obtained POD/PPTA composite fibers exhibited enhanced tensile strength and heat resistance compared to the pure POD fibers. The POD/10%PPTA composite fibers retained 68% strength and 43% elongation even after 24 h UV accelerated aging. The improvement of UV resistance was attributed to the photoinduced electron transfer reaction in POD/PPTA composite fibers, which has been demonstrated by both experimental and simulation studies.
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
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2015
·
IF 3.313
Qian Wen Bao,Wei Yuan Pan,Hao Liu,Bin Hong Liu,Zhou Peng Li
In this study, hydrogen release and uptake properties for composites of LiBH 4 with the conjugated polymer poly( p -phenylene) (PPP) were investigated. The incorporation of LiBH 4 with PPP led to a significant destabilization effect, decreasing the dehydrogenation temperature of LiBH 4 by 100 °C. Moreover, LiBH 4 could be regenerated at 450 °C under 9.0 MPa H 2 . By thorough analyses using XRD , HRTEM , FTIR , Raman, XPS as well as 11 B MAS NMR, the dehydrogenation product of LiBH 4 +PPP and the regeneration mechanism of LiBH 4 are elucidated. Also the reason of capacity degradation is discussed based on the analysis results. The formation condition of LiBH 4 was significantly moderated due to the presence of a simultaneously formed amorphous mixture of boron and carbon, which sheds light on the improvement of LiBH 4 reversibility .
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Frontiers in Chemistry
·
2022
·
IF 5.545
Ling Meng,Zhaoxia Sun,Guanghang Sun,Xiting Zhang,Meng Dan,Jin Long,Jian Hu
Herein, we reported that KOH impregnation can generate a large number of porous structures with fruitful nitrogen self-doped groups during the carbonized process for poly (p-phenylene terephthalamide) fiber and poly (p-phenylene benzobisoxazole) fiber (denoted as PPTA and PBO, respectively). The intrinsical insulation, volume change, and shuttle effect of polysulfides then can be more significantly improved for the PBO-coated separator than the PPTA case. The discharge capacity primary achieves 1,322 mA h/g, which retains 827 mA h/g even after 200 cycles at 0.2 C for the cell with PBO-coated separator. The reversible specific discharge capacity maintains 841 mA h/g with a Coulomb efficiency of 99.7% at 5 C. The nitrogen self-doped nanocarbon particles are etched by KOH with the simple one-step preparation, which has promising application as Li-S battery cathode.
研究领域:
电化学
·
能源材料
·
纳米材料科学
·
电池技术
·
功能高分子材料
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2017
·
IF 3.359
Yuan Gao,Zhenhuan Li,Bowen Cheng,Kunmei Su
In this study, Poly(p-phenylene sulfide) (PPS) microporous membrane was prepared via Thermally Induced Phase Separation (TIPS), and the superhydrophilic membrane was modified by nitric acid. After the interfacial reaction between PPS membrane and HNO 3 , a large number of hydrophilic groups, such as SO , SO 2 , C O, NH 2 and NO 2 groups, were introduced onto PPS membrane surface. When the treatment temperature was 50 °C, the characterized results indicated that the membrane became superhydrophilic with contact angle of 0° and pure-water flux of 154.95 L/m 2 h. And the membrane structure was not destroyed during the modification via HNO 3 . Furthermore, the performance of modified membrane on oil/water separation was studied and all of the separation efficiency were greater than 95% when the modified membrane was utilized to separate four different types of oil/water emulsions. In particular, the modified membrane was utilized to separate the chlorobenzene/water emulsion with the separation efficiency of 98.98%. Both carbonic ink solution and 1 wt% chlorobenzene/water emulsion were filtered with the treated membrane with acid/base solution (pH = 1, 7 and 14) to evaluate the modified membrane corrosion resistance of acid/base, and the characterized results indicated that modified membrane possessed the excellent acid/base corrosion resistance.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2023
·Vol. 15
·期 8
·1917
·
IF 5
Siheng Zhao,Bo Xu,Hao Shan,Qinglei Zhang,Xiangdong Wang
This work investigated the effect of different valence states of phosphorus-containing compounds on thermal decomposition and flame retardancy of polyethylene terephthalate (PET). Three polyphosphates—PBPP with +3-valence P, PBDP with +5-valence P and PBPDP with both +3/+5-valence P—were synthesized. The combustion behaviors of flame-retardant PET were studied and the structure–property relationships between the phosphorus-based structures with different valence states and flame-retardant properties were further explored. It was found that phosphorus valence states significantly affected the flame-retardant modes of action of polyphosphate in PET. For the phosphorus structures with +3-valence, more phosphorus-containing fragments were released in the gas phase, inhibiting polymer chain decomposition reactions; by contrast, those with +5-valence phosphorus retained more P in the condensed phase, promoting the formation of more P-rich char layers. It is worth noting that the polyphosphate containing both +3/+5-valence phosphorous tended to combine the advantage of phosphorus structures with two valence states and balance the flame-retardant effect in the gas phase and condensed phase. These results contribute to guiding the design of specified phosphorus-based structures of flame-retardant compounds in polymer materials.Keywords:polyethylene terephthalate (PET);flame retardant;valence states;phosphate
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanoscale
·
2025
·
IF 5.1
Mohammadreza Rostami,Biao Yang,Xiaochuan Ma,Sifan You,Jin Zhou,Meng Zhang,Xuefeng Cui,Haiming Zhang,Francesco Allegretti,Bing Wang,Lifeng Chi,Johannes Barth
n-Armchair graphene nanoribbons (nAGNRs) are promising components for next-generation nanoelectronics due to their controllable band gap, which depends on their width and edge structure. Using non-metal surfaces for fabricating nAGNRs gives access to reliable information on their electronic properties. We investigated the influence of light and iron adatoms on the debromination of 4,4”-dibromo-p-terphenyl precursors affording poly(para-phenylene) (PPP as the narrowest GNR) wires through the Ullmann coupling reaction on a rutile TiO2(110) surface, which we studied by scanning tunneling microscopy and X-ray photoemission spectroscopy. The temperature threshold for bromine bond cleavage and desorption is reduced upon exposure to UV light (240-395 nm wavelength), but the reaction yield could not be improved. However, in the presence of codeposited iron adatoms, precursor debromination occurred even at 77 K, allowing for Ullmann coupling and PPP wire formation at 300-400 K, i.e., markedly lower temperatures compared to the conditions without iron adatoms. Furthermore, scanning tunneling spectroscopy data reveal that adsorbed PPP wires feature a band gap of ≈ 3.1 eV.
研究领域:
材料科学
·
表面化学
✓ 已验证
DOI
PubMed
高影响因子
WATER AIR AND SOIL POLLUTION
·
2024
·Vol. 235
·期 7
·1-19
·
IF 3.8
Wu Qian,Liu Zhen,He Liqiong,Xiao Xilin,Tan Yan
As a kind of emerging contaminant, microplastics (MPs) widely exist in environments around the world and may carry other chemical pollutants. Besides, radioactive pollutants in water are getting more and more attention due to the discharge of wastewater from the Fukushima nuclear power plant. Among them, Uranium is an important fuel substance in nuclear power plants, which has toxicity of radioactivity and heavy metals. In order to research the interaction between MPs and uranium in water, batch experiments were conducted to study the adsorption behavior of radioactive heavy metal uranium (U(VI)) by ordinary PET MPs. The results showed that the adsorption amount of U(VI) onto PET increased (69.02%) after aging. The kinetic adsorption behavior of U(VI) could be explained by pseudo-second-order and Elovich models, and the isothermal adsorption behavior of U(VI) was well fitted by Langmuir and Sips models. The adsorption amounts were in the order of aged PET > virgin PET and ultrapure water > simulated freshwater. Besides, external diffusion and internal diffusion were included in the adsorption process. The adsorption capacity was affected by pH and salinity. The adsorption mechanisms included pore filling, electrostatic interaction, and surface complexation. The properties of MPs and the environment are the main factors affecting the adsorption process. The study elucidates the adsorption mechanism of U(VI) onto MPs in ultrapure water and simulated freshwater, aiming to assess the potential risk to aquatic environments where natural MPs and uranium ions coexist. Graphical Abstract
研究领域:
环境科学
·
放射化学
✓ 已验证
产品关联
DOI
高影响因子
BIOCHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 3.7
Jiaojiao Sun,Yaxing Pang,Ziyi Lei,Bo OuYang,Wanxian Lai,Yonghua Wang,Dongming Lan
Advancing the efficiency of polyethylene terephthalate (PET) degradation is pivotal for sustainable and versatile PET recycling. In this study, we initially screened eight esterases , pinpointing Pyrobaculum calidifontis VA1 esterase (PCEST) as markedly effective in decomposing PET intermediate products. Building on this discovery, we engineered fusion proteins combining a robust cutinase (HRC) with PCEST, connected by flexible glycine-serine linkers. We further optimized the linker length, the sequential arrangement and the enzymatic conditions of the conjugated enzymes . Notably, the synergistic activity of the HRC-PCEST fusion protein significantly enhanced the breakdown of PET, thereby promising to streamline recycling processes. Collectively, this methodology not only propels the efficiency of PET degradation but also broadens the horizons for sustainable and versatile PET waste management protocols.
研究领域:
生物化学
·
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2022
·
IF 9.224
Zishuai Wang,Yu Jin,Yaoqiang Wang,Zequn Tang,Shaojie Wang,Gang Xiao,Haijia Su
Due to the antibiodegradable properties, numerous plastics have been accumulated in the ecosystem and aggravate ecological pollution. Poly (ethylene terephthalate) (PET) is among the most used plastics. Glycolysis of PET is a useful approach to solve the waste PET pollution and obtain bis(2-hydroxyethyl) terephthalate (BHET). In this paper, waste PET was efficiently depolymerized through glycolysis catalyzed by cyanamide. In particular, compared with the previously reported catalyst, cyanamide is more readily available and can be used directly in catalysis without a complex preparation process. Under optimal conditions, PET was completely depolymerized with up to nearly 100% BHET yield. Even at a temperature as low as 150 °C, a good BHET yield can be obtained. The application potential of this glycolysis procedure was demonstrated by its excellent performance in the glycolysis of various real PET wastes like transparent and opaque PET samples and polyester foam and by the high quality of the obtained BHET products. The mechanism was studied by 1H NMR analysis, and DFT calculations showed that the higher activity of cyanamide than its trimer, melamine, is due to the stronger hydrogen bonds formed between cyanamide and PET or ethylene glycol.
研究领域:
环境科学
·
材料化学
·
催化反应
✓ 已验证
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2021
·
IF 5.161
Jie Zhang,Xiang Zhang,Yuying Zheng
Graphene (G) is an excellent protection material, but suffering corrosion-promotion effect because of its intrinsic high electrical-conductivity. Herein, a facile strategy is presented to effectively lower the conductivity of the G by the encapsulation of insulating poly(p-phenylenediamine) (PpPD). The obtained G@PpPD, which delivers an extremely low conductivity of 3.5×10 −7 S cm -1 , were then mixed with polyvinyl-butyral (PVB), forming a compact composite coating that can effectively protect Q235 steel from being corroded over a very long period. Such a superior anticorrosion property can be owing to the synergistic effect between impermeable graphene and insulated PpPD, which not only hinders the diffusion of the corrosive media, but also inhibits the corrosion-promotion activity of the graphene. This effective strategy may provide valuable enlightenment for the further development of graphene-based polymer anticorrosive coatings with long-lasting corrosion resistance .
研究领域:
材料科学
·
腐蚀与防护
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry A
·
2017
·Vol. 5
·期 26
·13610-13624
·
IF 8.867
Qiang Shi,Lei Ni,Yufeng Zhang,Xianshe Feng,Qiuhui Chang,Jianqiang Meng
A new approach to improving the compaction resistance and polyamide skin layer adhesion onto the substrate in thin film composite (TFC) membranes was developed. It was based on in situ polymerization of p-phenylene terephthamide (PPTA) in a polysulfone (PSf) solution prior to membrane casting via the phase inversion process, thereby forming a PPTA-embedded PSf substrate. The TFC membrane was prepared by interfacial polymerization on such (PPTA/PSf) substrates. The crystal structure of the PPTA polymerized in the PSf/NMP solution was investigated by XRD and TEM. The immobilization of PPTA in the PSf substrate was confirmed by FTIR and XPS. The surface properties of the PPTA/PSf substrates were characterized by FESEM, AFM and WCA measurements. Incorporating PPTA into the substrates resulted in more open porous structures and a thinner dense layer, as well as a rougher and more hydrophilic surface. Both the compaction resistance of the TFC membrane and the polyamide skin layer adhesion onto the substrates were improved by the presence of PPTA. The TFC membranes exhibited a typical nanofiltration performance with salt rejections in the order of Na2SO4 > MgSO4 > MgCl2 > NaCl.
研究领域:
材料科学
·
膜技术
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2023
·Vol. 15
·期 7
·1713
·
IF 5
Bo Xu,Shouao Zhu,Siheng Zhao,Xiangdong Wang
A high-phosphorus-content polyphosphonate (PBDA), containing two phosphorus-based structures: phosphaphenanthrene (DOPO) and phenyl phosphonate groups, was synthesized and used in flame retardant polyethylene terephthalate (PET). Good self-extinguishing property (high UL 94 grade and LOI value), superior flame retardancy (lower heat/smoke release), and high quality retention (high carbon residue) were endowed to PET by PBDA. When 10 wt% PDBA was added, the peak heat release rate (pHRR), total heat release (THR), and total smoke rate (TSR) of PDBA/PET were found to be significantly reduced by 80%, 60.5%, and 21%, respectively, compared to the pure PET, and the LOI value jumped from 20.5% for pure PET to 28.7% with a UL-94 V-0 rating. The flame-retardant mode of action in PET was verified by thermogravimetric analysis-Fourier transform infrared (TGA-FTIR), pyrolysis gas chromatography/mass spectrometry (Py-GC/MS), real-time FTIR, and scanning electron microscopy (SEM). Phosphaphenanthrene and phosphonate moieties in PDBA decomposed in sequence during heating, continuously releasing and keeping high-content PO· and PO2· radicals with a quenching effect and simultaneously promoting the formation of viscous crosslinked char layers causing a high barrier effect. PDBA mainly acted in the gas phase but the condensed-phase flame retardant function was also considerable.Keywords:flame retardant;polyphosphonate;poly(ethylene terephthalate);high phosphorus content
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）