POLYMER BULLETIN
·
2024
·
IF 3.1
Wang Yunfei,Gao Shanjun,Yin Nian,Chen Yuhan,Shen Chunhui,Yu Yi
A new hyperbranched charring-foaming agent (PCAT) containing triazine and triazole groups was successfully synthesized and characterized, and its special pyrolysis behavior was analyzed. It was combined with PAPP as an acid source to form an intumescent flame-retardant system. The composite with 20% flame retardants containing PAPP/PCAT (3:1) showed better flame-retardant and smoke suppression properties. The LOI of the PP/PAPP/PCAT composite increased to 30.2% and achieved UL-94 V-0 rating when the mass ratio of PAPP/PCAT was 3:1. In cone calorimetry experiments, it was demonstrated to reduce PHRR and THR by 84.7% and 48.9%, respectively. Meanwhile, the PSPR and TSP were also reduced by 77.9% and 56.2%, respectively, relative to PP. This indicates that the PP modified by partially doping PCAT in PAPP has significantly enhanced heat dissipation and smoke suppression performance, thus performing higher fire safety. In terms of FRI, PP/PAPP/PCAT composite was considered to be of “good” flame retardancy. Thermal gravimetric analysis demonstrated that PCAT significantly improved the char yield of PP when combined with PAPP. The morphology and properties of the residue showed that PP/PAPP/PCAT could produce a significant expanded foam insulating carbon layer, and the graphitization degree of the residual carbon was enhanced. The investigation of their water resistance demonstrated that the PP/PAPP/PCAT composite still obtained a UL-94 V-0 rating after 168-h soaking in water.
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
JOURNAL OF SOLID STATE CHEMISTRY
·
2022
·
IF 3.656
Wen-Feng Zhou,Yi-Min Wei,Zhi-Wei Xiao,Yan Jiang,Yan-Kai Zhang,Zhen-Wei Zhang,Hui Hu,Longlong Geng,Da-Shuai Zhang,Yong-Zheng Zhang,Xiuling Zhang,Shujuan Zhuang
A new dual-cage-based porous metal-organic framework (MOF, termed DZU-113) assembly from the triazole-carboxylate linker and the Cu(II) paddle-wheel unit was solvothermally constructed. The structure of DZU-113 was determined by single-crystal X-ray diffraction, being consisted of the octahedral cage with an internal diameter of approximately 0.4 nm, and the spindle nano-cage with internal pores of about 0.8 nm × 2.2 nm, respectively. Specially, the uncoordinated N atoms of triazole groups are distributed in the bottleneck windows of the spindle nano-cage, serving as open functional sites. DZU-113 has permanent porosity with the Brunauer−Emmett−Teller surface area of 1207 m 2 g −1 . The CO 2 adsorption test demonstrated that the total uptake of DZU-113 can reach 66.7 cm 3 g −1 at 298 K, and 112.0 cm 3 g −1 at 273 K, 1 bar. Moreover, it achieves robust catalytic performance for the cycloaddition of CO 2 and epoxides under mild conditions.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF PHYSICAL CHEMISTRY B
·
2013
·
IF 3.607
Baohua Yue,Liuming Yan,Shuaiyuan Han,Liqing Xie
The proton transport pathways in an acid–base complex consisting of a phosphonic acid group and a 1,2,3-triazolyl group were studied using density functional theory (DFT) calculations in terms of stable configurations and transition states of the molecular or ionic dimers and trimers and verified by proof-of-concept experiments including experimental measurements of overall conductivity and 1H NMR and FTIR spectroscopy of the methylphosphonic acid (MPA) and 1,2,3-triazole (Tri) complex as well as overall proton conductivity of polymeric blend of poly(vinylphosphonic acid) (PVPA) and poly(4-vinyl-1H-1,2,3-triazole) (PVTri). From the DFT calculations of dimers and trimers composed of ethylphosphonic acid (EPA), Tri, and their deprotonated counterparts, it was concluded that the intermolecular hydrogen bonds of the transition states corresponding to proton transport are much shorter than those of stable configurations, but the O–H and N–H bonds are much longer than those of stable configurations. The tautomerization activation energy decreases from 0.927–1.176 eV in Tri–Tri dimers to 0.336–0.444 eV in the EPA–Tri dimers. From the proof-of-concept experiments, about a 50 fold increase in overall conductivity was observed in the MPA–Tri complex consisting of 10% (molar ratio) MPA compared to pure Tri, and the calculated activation energy is consistent with the experimental activation energy evaluated from temperature dependence of proton conductivity of pure Tri and the MPA–Tri complex. In addition, the fast proton exchange between MPA and Tri, consistent with the DFT calculations, was verified by 1H NMR and FTIR spectroscopy. Finally, a polymeric blend of PVPA and PVTri was prepared, and its proton conductivity at about 2.1 mS·cm–1 in anhydrous state at 100 °C was observed to be significantly higher than that of PVPA or of poly(VPA-co-1-vinyl-1,2,4-triazole). The proton conductivity of the polymeric PVPA and PVTri blend in humidity state is in the same range as that of NAFION 117.
研究领域:
化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Small
·
2020
·Vol. 16
·期 37
·2003162
·
IF 11.459
Chongbei Wu,Guanhang Yu,Yue Yin,Yuze Wang,Li Chen,Qing Han,Junwang Tang,Bo Wang
Conjugated polymers are promising light harvesters for water reduction/oxidation due to their simple synthesis and adjustable bandgap. Herein, both cyanamide and triazole functional groups are first incorporated into a heptazine-based carbon nitride (CN) polymer, resulting in a mesoporous conjugated cyanamide-triazole-heptazine polymer (CTHP) with different compositions by increasing the quantity of cyanamide/triazole units in the CN backbone. Varying the compositions of CTHP modulates its electronic structures, mesoporous morphologies, and redox energies, resulting in a significantly improved photocatalytic performance for both H 2 and O 2 evolution under visible light irradiation. A remarkable H 2 evolution rate of 12723 µmol h −1 g −1 is observed, resulting in a high apparent quantum yield of 11.97% at 400 nm. In parallel, the optimized photocatalyst also exhibits an O 2 evolution rate of 221 µmol h −1 g −1 , 9.6 times higher than the CN counterpart, with the value being the highest among the reported CN-based bifunctional photocatalysts. This work provides an efficient molecular engineering approach for the rational design of functional polymeric photocatalysts.
研究领域:
材料科学
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化学工程
·
能源科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Sensors & Diagnostics
·
2023
·Vol. 2
·期 4
·902-908
·
IF 0
Xiaotao Liu,Xueyi Zheng,Chunqiu Xia,Liangqia Guo
Nanozymes have attracted great interest in the field of biotechnology, (bio)sensing, and environmental monitoring. Herein, a co-doping strategy is proposed to enhance the peroxidase-like activity of graphitic carbon nitride (g-C3N4). Cu2+ and triazole group co-doped graphitic carbon nitride (g-C3N5-Cu2+) was derived from thermal polymerization of 3-amino-1,2,4-triazole and then coordination with Cu2+. g-C3N5-Cu2+ nanosheets (NSs) could catalyze the oxidation reaction of 3,3′,5,5′-tetramethylbenzidine (TMB) by H2O2 under neutral conditions, yielding 10.9-fold better catalytic activity than g-C3N4 NSs. Reactive oxygen species scavenging experiments indicated that ˙OH played a crucial role during the catalytic process. When glutathione (GSH) was introduced, the absorbance of the system decreased because of the reduction of the oxidation product of TMB by GSH. The colorimetric method demonstrated a sensitive response for GSH with a linear range of 0.8–33.3 μmol L−1 and a limit of detection of 0.3 μmol L−1. The sensitivity is higher than most other peroxidase mimetic-based colorimetric methods for GSH. Finally, the feasibility for the detection of GSH in HeLa cells was demonstrated.
研究领域:
生物技术
·
环境监测
·
分析化学
✓ 已验证
DOI
LANGMUIR
·
2024
·
IF 3.7
Shichen Mao,Baogang Wang,Shanshan Dai,Hongsheng Lu
Long running-in period and corrosion problems have greatly hindered the practical applications of poly(ethylene glycol) (PEG) lubricants. In this work, benzotriazole group-terminated carbon dots (BT-CDs) were specifically synthesized through a facile solvothermal method. The benzotriazole groups on BT-CD surfaces not only imparted them excellent dispersibility in the PEG base oil but also brought in outstanding anticorrosion ability for BT-CDs. With the aid of the coordination effects between benzotriazole groups and metal atoms, the BT-CDs could quickly and solidly adsorb onto the steel surface to form a dense adsorption layer, which resulted in an amazing phenomenon, i.e., the disappearance of the running-in period for the friction test. Adding 5.0 wt % BT-CDs reduced the friction and wear of PEG200 by 49.16 and 49.52%, respectively. When the duration was prolonged from 20 to 120 min, these values were further enlarged to 53.77 and 60.71%. The worn surface characterization demonstrated that the BT-CDs induced the generation of robust lubricating films on the frictional interfaces, accounting for their distinguished tribological performance. Considering the superior anticorrosion ability and the potential possibility of avoiding the running-in period, the BT-CDs are expected to be developed as particularly promising additives toward PEG.
研究领域:
材料科学
·
化学工程
·
机械工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
·
2021
·
IF 3.975
Shilin Lai,Jinbin Gao,Xingquan Xiong
Development of efficient, green and recyclable heterogeneous catalysts for the chemical conversion of CO 2 into cyclic carbonates with excellent yields under atmospheric pressure condition is still a very challenging task. Herein, a class of biomass-derived hyper-cross-linked porous heterogeneous catalysts MPAc-Br and MPAc-OH-Br, based on easily available and sustainable rosin, was synthesized by Friedel–Crafts polymerization and the further N -alkylation of triazole groups. Compared with MPAc-Br, the bifunctional catalyst MPAc-OH-Br (bearing triazole IL groups and -OH groups) exhibited higher catalytic activity for direct chemical conversion of CO 2 into cyclic carbonates (up to 99% yields) under metal-, solvent-free and atmospheric pressure conditions. The rosin-based porous molecular structure and bifunctional groups on the surface of MPAc-OH-Br played a very important role in the promoting the cycloaddition of CO 2 with epoxides under the optimal conditions. Furthermore, MPAc-OH-Br exhibited good stability and reusability (96% yield after 10 recycles).
研究领域:
催化化学
·
环境科学
·
绿色化学
✓ 已验证
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2020
·
IF 7.632
Wenchang Liu,Zhe Wang,Xinming Du,Jingmei Xu,Chang Liu,Haiqiang Li,Zhaoyu Chen,Chunmei Wang,Hao Chen,Li Chen
The practice of site control for functional groups to achieve better interactions has become popular in recent years. Capitalizing on such developments, sulfonated 5-carboxybenzotriazole (SCBTA), serving as a new monomer that combines multiple functional groups, is grafted onto pendant chains of poly(arylene ether ketone) (PAEK) via an amidation reaction to fabricate a series of novel proton-exchange membranes (NmAn-SCBTA). The structure of the resulting membranes is confirmed by 1H NMR and Fourier transform infrared (FT-IR). Transmission electron microscopy (TEM) and small-angle X-ray spectroscopy (SAXS) analyses reveal well-defined microphase-separated structures. Among these samples, a membrane having an amino bisphenol monomer content of 70% (N7A3-SCBTA) exhibits high conductivity (0.089 S·cm–1, at 90 °C), oxidative stability (95.7%), and tensile strength (65.74 MPa), while its selectivity is as high as 91.9 × 104 S·s·cm–3 at 25 °C; this value is even more than 27 times that of recast Nafion (3.3 × 104 S·s·cm–3). These results indicate that there is great potential for these membranes to be used in direct methanol fuel cells (DMFCs).
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
SOLID STATE IONICS
·
2018
·
IF 2.751
Guangbo Zeng,Baohua Yue,Xuejiao Li,Liuming Yan
A novel phosphonic acid and triazolyl functionalized poly(ether sulfone) (PES-TriPA) containing simultaneously phosphonic acid and triazolyl side groups is synthesized. The PES-TriPA is prepared by polycondensation of phosphonated bisphenol (PBP) and 3,3′-diethynyl-4,4′-difluorodiphenylsulfone, followed by click reaction to introduce triazolyl groups and hydrolysis to free phosphonic acid groups. Phosphonic acid functionalized poly(ether sulfone) (PES-PA) and triazolyl functionalized poly(ether sulfone) (PES-Tri) are also synthesized for comparison with PES-TriPA. The proton conducting polymers are hot-pressed into proton exchange membranes , and the membrane morphologies, proton conductivities , oxidation and thermal stabilities, water uptakes and methanol permeabilities are characterized. PES-TriPA exhibits more excellent comprehensive properties in comparison with PES-PA and PES-Tri. At 100 °C and 90% relative humidity (RH), the proton conductivity of PES-TriPA reaches 113.0 mS cm −1 , in comparison with 55.7 mS cm −1 for PES-PA and 4.3 mS cm −1 for PES-Tri. PES-TriPA also shows better oxidation stability with 95.7% weight left after Fenton's test at 80 °C for 120 h, while only 68.7% left for PES-PA and 75.7% left for PES-Tri. In addition, PES-TriPA exhibits favorable thermal stability and water uptake compared with PES-PA and PES-Tri. Moreover, the methanol permeability of PES-TriPA is only 0.24 × 10 −8 cm 2 s −1 , which is lower than these of PES-PA and PES-Tri with 0.77 × 10 −8 cm 2 s −1 and 1.20 × 10 −8 cm 2 s −1 , respectively. These superior characteristics are attributed to the synergetic effect between the phosphonic acid groups and triazolyl groups caused by the intermolecular hydrogen bonding interaction throughout the PES-TriPA acid-base amphoteric polymer.
研究领域:
高分子科学
·
材料科学
·
电化学
✓ 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）