POLYMERS FOR ADVANCED TECHNOLOGIES
·
2022
·Vol. 33
·期 7
·2265-2275
·
IF 3.348
Xuan Fei,Yingkang Zhu,Jinggang Wang,Zhen Jia,Xiaoqing Liu
To enhance the crystallization of poly(butylene 2,5-furandicarboxylate) (PBF) thus substitute its petroleum-based analogue poly(butylene terephthalate) (PBT), a series of high molecular weight poly(butylene-co-1,4-cyclohexanedimethylene 2,5-furandicarboxylate) (PBCF) copolyesters with low contents (0–19 mol%) of 1,4-butanediol (BDO) are synthesized from 2,5-furandicarboxylic acid (FDCA), 1,4-cyclohexanedimethylene (CHDM) and BDO. Their chemical structures and compositions are confirmed by nuclear magnetic resonance ( 1 H NMR and 13 C NMR). Their number average molecular weights are from 20,500 to 36,100 g/mol with the polydispersity index ( Ð ) of 1.67–1.99. The thermal stability and crystallization behaviors are investigated by thermogravimetric analyzer (TGA) and differential scanning calorimeter (DSC). Results show that PBCFs demonstrate comparable crystallization rate to PBT as the crystallization half time is from 18 to 29 s and the melting enthalpy is 34.1–41.4 J/g as well as the higher melting temperature of 238–263°C than 225°C for PBT. In addition, PBCFs exhibit excellent mechanical properties of tensile modulus between 1220 and 1510 MPa. These investigations suggest that a moderate amount CF unit can improve the melting temperature and enhance the originally weak crystallizability of furan-based polyesters. Generally, PBCFs can be the engineering plastic with satisfied thermal and mechanical performance.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
HYDROMETALLURGY
·
2020
·
IF 3.338
Xi Chen,Xincun Tang,Zhihao Rong,Liping Wu,Pin Deng,Yang Wang,Xing Li,Liuchun Huang,Wei Dang
This paper presents an eco-friendly method for recovery of cadmium by solvent extraction and stabilization of arsenic through one-pool treatment on arsenic-rich flue dust. The morphology-controlled scorodite can be realized by adjusting reaction temperature. It is worth emphasizing that the arsenic-immobilized scorodite precipitates have superior crystallinity which exhibit excellent safety for long-term storage. In addition, the advantage brought about by taking hydrogen peroxide as leaching agent is that leachate is weakly acidic, which removes the need to add a large amount of neutralizing agent and facilitates the synthesis of scorodite. The results show that 97.3% of arsenic was leached from arsenic-rich flue dust and then 92.8% of the leached arsenic was transferred into scorodite with the recovery of 81.5% of cadmium under the optimal conditions. We hope that this work will provide a facile and environmentally friendly protocol for those interested in developing a new strategy for simultaneously recovering and stabilizing toxic heavy metal ions from industrial dust.
研究领域:
环境科学
·
冶金工程
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 19
·11244-11252
·
IF 3.108
Hongwei Cao,Feixuanyu Qi,Ruowang Liu,Fengtao Wang,Caixia Zhang,Xiaoni Zhang,Yuye Chai,Lanlan Zhai
Hydrogen bonding was used to enhance the crystallinity and thus increase the phase change enthalpy of thermoplastic poly(ethylene glycol)-based polyurethane. With novel hydrogen bonding between two hard segments (NH⋯N) in N-methyldiethanolamine-extended polyurethane (NPU), the intensity of the NH⋯OC hydrogen bond between two hard segments increased, while that of the NH⋯O hydrogen bond between soft and hard segments decreased. The crystallinity and energy storage capability of NPU benefited from these and was thus enhanced. The phase change enthalpy was approximately 140 J g−1, which is very close to the highest value reported for cross-linked polyurethane. In addition, the crystallinity and crystallite perfection of NPU increased with the regular arrangement of soft segments and the microphase separation between soft and hard domains. The influence of the three different hydrogen bonds on the phase change enthalpy, crystallinity, crystallization morphology and microphase structure of the soft segment was discussed.
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
·
2018
·Vol. 136
·期 6
·2363-2371
·
IF 2.209
Zhang Yue-Fei,Lin Xiang-Feng,Chen Shuai
A highly efficient compound nucleating agent of carboxylated graphene/calcium pimelate (Gra/CaPi) for isotactic polypropylene (iPP) was prepared. The structure of Gra/CaPi was investigated by Fourier-transform infrared spectroscopy. The effects of Gra/CaPi on the crystallization and melting behaviors and crystalline morphology of iPP were investigated by differential scanning calorimetry, wide-angle X-ray diffraction and polarized optical microscopy. The results showed that CaPi and Gra were combined by chemical bonds, improved the dispersibility and nucleation ability of Gra in iPP. When the addition amount of Gra/CaPi in iPP was 0.3 mass%, the crystallization peak temperature was increased by 8.0 °C and the relative content of β -crystal in iPP reached up to 0.868 compared with that of pure iPP.
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
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2022
·
IF 6.056
Chuangchuang Zhang,Shwetha Narayanamoorthy,Shuangxi Ming,Kehu Li,Dennis Cantre,Zhongquan Sui,Harold Corke
This study aims to explore diversity in rheological properties, structure and digestibility of starches isolated from 16 common bean ( Phaseolus vulgaris L.) varieties from Europe and Asia. All common bean starches showed C A -type (closer to A-type) crystallinities. Relative crystallinity varied from 27.8% to 32.9% with a similar coefficient of variation (CV: 5.0%–6.0%) to 1045/1014 cm −1 ratio (varied from 0.429 to 0.508). A peak position shift occurred at 989 and 1014 cm −1 . The peak intensity at 989, 1014 and 1045 cm −1 varied greatly and the variation followed the order: at 989 > 1014 > 1045 cm −1 . A great variation was also observed for the presence of hydroxyl group and the C–O bond stretching. Rapidly digestible starch, slowly digestible starch and resistant starch contents varied from 61.5% to 73.0% (CV: 4.7%), 0.3% to 7.2% (CV: 53.7%) and 23.9% to 35.4% (CV: 11.4%), respectively. CV of storage modulus (G′) and loss tangent (tan δ) were 29.4%–39.4% and 11.9%–36.1%, respectively. G′ max (maximum G′ during heating) varied from 2.52 to 10.32 kPa. These starches showed high G′. This study indicates extensive variation in starch properties among these common bean varieties, which may be useful for selecting varieties for processing, or selecting genotypes for plant breeding.
研究领域:
食品科学
·
植物学
✓ 已验证
产品关联
DOI
高影响因子
Foods
·
2023
·Vol. 12
·期 7
·1415
·
IF 5.2
Shenglan Lu,Xueying Li,Xunran Wei,Caihuan Huang,Jie Zheng,Shiyi Ou,Tao Yang,Fu Liu
In contrast to their well-known physiological properties, phytochemicals, such as flavonoids, have been less frequently examined for their physiochemical properties (e.g., surface activity). A natural quercetin self-stabilizing Pickering emulsion was fabricated and characterized in the present study. The antisolvent precipitation method was used to modify quercetin (in dihydrate form), and the obtained particles were characterized by light microscope, atom force microscope, XRD, and contact angle. The antisolvent treatment was found to reduce the particle size, crystallinity, and surface hydrophobicity of quercetin. We then examined the effects of the antisolvent ratio, particle concentration, and oil fraction on the properties of the quercetin particle-stabilized emulsions. In addition, increasing the antisolvent ratio (1:1~1:10) effectively improved the emulsification performance of the quercetin particles. The emulsion showed good storage stability, and the particle size of the emulsion decreased with the rising particle concentration and increased with the rising oil phase ratio. The findings indicate that natural quercetin treated with antisolvent method has a good ability to stabilize Pickering emulsion, and this emulsion may have good prospective application potential for the development of novel and functional emulsion foods.Keywords:quercetin;Pickering;antisolvent precipitation;crystalline
研究领域:
食品科学
·
胶体化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
·
2017
·
IF 4.811
Ping Zhu,Zhongji Gu,Shu Hong,Hailan Lian
For the first time in this study, chitin was solely extracted from lobster shells through a fast, easy and eco-friendly method using deep eutectic solvents (DESs), consisting of mixtures of choline chloride–thiourea (CCT), choline chloride–urea (CCU), choline chloride–glycerol (CCG) and choline chloride–malonic acid (CCMA). The physiochemical properties of the isolated chitins were compared with those of the chemically prepared one and commercial one from shrimp shells. Results showed that CCT, CCU and CCG DESs had no important effect on the elimination of proteins and minerals, while chitin obtained by CCMA DES showed a high purity. The yield (20.63 ± 3.30%) of chitin isolated by CCMA DES was higher than that (16.53 ± 2.35%) of the chemically prepared chitin. The chitin obtained by CCMA DES could be divided into two parts with different crystallinity (67.2% and 80.6%), which also had different thermal stability. Chitin from lobster shells showed porous structure, which is expected to be used for adsorption materials and tissue engineering.
研究领域:
生物化学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
Materials Today Nano
·
2025
·
IF 8.2
Pingan Chen,Sizeng Hong,Xiangcheng Li,Yingli Zhu,Fu Chen,Mengke Qiao
Carbon nanofibers can be widely used in the field of electromagnetic wave absorption due to corrosion resistance, low density and good chemical stability. Here, we report a strategy to achieve strong microwave absorption capability by adjusting the crystallinity of carbon nanofibers containing Al 2 O 3 and TiO 2 . TiO 2 with Ti 3 C 2 T x MXene as a precursor decreases the crystallization temperature of Al 2 O 3 from 1400 °C to 800 °C in the carbon nanofibers. The diameter distribution of carbon nanofibers is uniform, though the surface of carbon nanofibers is getting rough with Ti 3 C 2 T x content increasing. The minimum reflection loss of carbon nanofibers is -55.78 dB at a thickness of 4.32 mm; the effective absorption bandwidth reaches 5.41 GHz (12.59-18 GHz) at a thickness of 1.67 mm, almost covering the Ku band. The excellent microwave absorption performance can be attributed to the synergistic effect of the non-crystalline carbon matrix and crystalline Al 2 O 3 /TiO 2 , in which the former improves impedance matching with free space, while the latter enhances the attenuation capability to the electromagnetic wave.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Yun Wang,Jian Chen,Huilin Zhou,Chenxi Liu,Yanfeng Chen,Junmin Xia,Qingqing Yang,Lihui Liu,Shufen Chen
Although metal halide perovskites (MHPs) have demonstrated remarkable external quantum efficiencies (EQEs) in red and green light-emitting diodes (LEDs), the blue ones confront efficiency and stability problems due to the high defect density in the perovskite films. Large amounts of defect passivation strategies are successfully developed to improve the device performance. Nevertheless, the influence of the molecular configuration of the passivators on the perovskite crystallization process has not been comprehensively investigated so far. Here, we investigate the effect of the phenyl ring on the perovskite crystallization dynamics and the passivation effect. The additive with a phenyl ring performs the π–π stacking ability with phenethylammonium (PEA+) molecules, resulting in a deteriorated crystallinity and a weakened passivation ability. Conversely, the additive without the phenyl ring is helpful to promote the participation of PEA+ molecules in the crystalline process, leading to a higher crystallinity and a stronger passivation effect. As a result, the EQE of the blue perovskite LED has increased from 4.72 to 11.06% by using the phenyl ring-free additive. Therefore, it is advisible to develop the conjugated nonplanar additives in the PEA+-assisted quasi-two-dimensional perovskites. This finding may enlighten the rational design of defect passivators for highly efficient perovskite LEDs.
研究领域:
材料科学
·
光电子学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COMPOSITES PART B-ENGINEERING
·
2024
·
IF 12.7
Quan Yang,Pingan Chen,Xiangcheng Li,Yingli Zhu
To achieve strong electromagnetic wave absorbing properties, it is important to have good impedance matching, moderate electrical conductivity , and high polarization loss, particularly at low frequency. However, meeting these requirements for polymer-derived ceramics remains challenging. This paper proposes a simple approach to addressing this challenge by adjusting the crystallinity and defects of SiBCN ceramics. The addition of Sm as a catalyst and tailored heating temperatures were used to create SiBCN ceramics with adjustable crystallinities and defective nanograins. The controlled crystallinity provided good impedance matching, while the tailored defective nanograins offered high polarization loss. The combination of these factors results in high-performance electromagnetic wave absorption, with the SiBCN ceramics achieving a minimum reflection loss of −59.13 dB at 3.6 GHz and an effective attenuation bandwidth of 6.87 GHz with a thickness of 2.22 mm. This study provides an effective strategy for the design and fabrication of strong EMW absorbing materials.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF VINYL & ADDITIVE TECHNOLOGY
·
2022
·Vol. 28
·期 3
·459-473
·
IF 2.297
Xiangming Yang,Xiaoling Song,Yijing Wang,Erlei Yu,Zhong Wei
Bio-based phytic acid is a nontoxic naturally occurring compound and has the potential for use in polymers for flame retardancy due to its high phosphorus content. In this work, two novel phytic acid-based compounds, phytyl octyl glycidyl ether (PAOc) and phytyl phenyl glycidyl ether (PAPh), were prepared through the addition esterification of 2-ethylhexyl glycidyl ether and phenyl glycidyl ether with phytic acid. The chemical structure of PAOc and PAPh were confirmed by 1 H NMR, 31 P NMR, and FTIR spectra. The mechanical, thermal, and fire performances of the PLA/PAOc and PLA/PAPh blends were investigated by various tests including mechanical, thermal (DSC, TGA), morphological (SEM), and flammability (LOI, UL-94). The results showed that the addition of PAOc and PAPh improved the thermal stability of PLA through hydrogen bonding. PAPh was more effective to improving the mechanical properties and crystalline properties of PLA than PAOc. When PAPh was 5 wt%, the elongation at break of PLA increased from 2.9% to 16.7%, the tensile strength increased from 32 to 37 MPa, and the crystallinity increased from 30.6% to 36.7%. Moreover, introduction of phenyl group was beneficial to phytic acid improving the flame retardant properties of PLA. At an addition level of 10 wt%, the LOI of PLA/PAPh reached 27.5% and achieved UL-94-V0 rating while improving the mechanical properties.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
THIN SOLID FILMS
·
2021
·
IF 2.183
Haipeng Di,Wei Jiang,Hao Sun,Chen Zhao,Feiyi Liao,Yiying Zhao
Halide perovskite single crystal thin films (SCTFs) have attracted extraordinary attentions due to the promising potential applications as the high-performance optoelectronic devices. However, fabricating the high-quality and large-area perovskite SCTFs is still the main challenge for the future commercialization. In this work, systematical investigations show that the evaporation of methylamine can lead to the precipitation of the PbBr 2 phase, which is one of the major causes of the poor crystallinity and the surface morphology . A simple strategy is demonstrated to improve the crystallinity and properties of MAPbBr 3 SCTFs using the mainstream space-confined method, by controlling the evaporation of the methylamine during the crystal growth, i.e. the growth temperature and the PbBr 2 /MABr molar ratio in precursor. The crystal quality of MAPbBr 3 SCTFs can be improved by lowering the growth temperature and decreasing the PbBr 2 /MABr molar ratio in the precursor. The best MAPbBr 3 SCTF is obtained at 50 °C with the PbBr 2 /MABr molar ratio of 0.85 in precursor solution. The SCTF is in square shape (~2 mm × 2 mm) and with a full width of half-maximum of the rocking curve of (100) crystal plane of 0.051 o . These results will inspire the further explorations in fabricating the high-quality perovskite SCTFs.
研究领域:
材料科学
·
光学工程
✓ 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）