Polymer Chemistry
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2016
·Vol. 7
·期 48
·7427-7435
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IF 5.687
Nafeesa Mushtaq,Guofei Chen,Lala Rukh Sidra,Yang Liu,Xingzhong Fang
Two novel series of highly organosoluble and curable polyimides containing pendant nitrile groups PI (a–d) and phthalonitrile-terminated polyimides PN-PI (a–d) were prepared by solution polycondensation of isomeric bis(chlorophthalimides)s and 2,6-dichlorobenzonitrile with 4,4′-thiobisbenzenethiol. The inherent viscosities of these copolymers were in the range of 0.37–0.59 dL g−1 in N-methyl-2-pyrrolidone (NMP) at 30 °C. The phthalonitrile and pendant nitrile groups in isomeric poly(thioether-ether-imide)s were thermally crosslinked without a catalyst through thermal curing up to 280–360 °C, which led to the transformation from thermoplastic polymers to thermosetting polymers. All PIs before and after crosslinking were characterised by gel permeation chromatography (GPC), differential scanning calorimetry (DSC) and Fourier transform infrared (FT-IR) spectroscopy. PN-PI (a–d) and PI (a–d) were found to be highly soluble in some solvents, such as chloroform, dimethylacetamide, m-cresol, dimethlyformamide and N-methyl-2-pyrrolidone, while the crosslinked polymers were insoluble in all tested solvents. The crosslinking results of pendant nitrile and terminal phthalonitrile groups are also compared. Both series of PIs showed high thermal stability based on 5% weight loss temperature (T5%) in the range of 471–509 °C and increased up to 35 °C after thermal curing. Polyimides showed high glass transition temperatures (Tgs) ranging from 191–213 °C as determined by DSC, but no detectable Tg was observed after thermal heating, indicating the crosslinked structure of PIs. The mechanical properties also enhanced after the crosslinking of the copolymers. The tensile modulus and strength of the cured PI films were in the range of 3.3–4.7 GPa and 68–122 MPa, respectively, which were up to 62% and 35% higher than the uncured films.
研究领域:
材料科学
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高分子化学
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DOI
高影响因子
POLYMER COMPOSITES
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2018
·
IF 1.943
Mehdi Derradji,Abdeldjalil Zegaoui,Aboubakr Medjahed,Abdul Qadeer Dayo,Jun Wang,Yitagesu Bereket Arse,Wen-bin Liu,Yu-Guang Liu
This work relates for the first time ever the use of natural fibers to reinforce the high performance phthalonitrile resins. The excellent thermal stability of the basalt fibers (BFs) allows them to be the only natural fibers resisting the high curing temperatures of the phthalonitrile resins. Based on this promising combination, high performance polymer composites were prepared and their performances were scrutinized in terms of mechanical properties and nuclear shielding efficiency. The BFs which initially underwent a silane surface modification provided materials with metal equivalent tensile and flexural properties. For instance, the composite containing 15 plies of treated fibers achieved the tensile and flexural strengths of 700 and 780 MPa, respectively. Additionally, the same composite stopped 36% of the incident highly ionizing gamma rays. Meanwhile, morphological investigations further confirmed the enhancement seen in the mechanical properties. Overall, the studied composites can be used as advanced materials in extremely exigent applications. POLYM. COMPOS., 40:E912–E919, 2019. © 2018 Society of Plastics Engineers
研究领域:
材料科学
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核工程
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DOI
高影响因子
POLYMER TESTING
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2022
·
IF 4.931
Xiaoqian Xu,Mingzhen Xu,Tian Liu,Dengxun Ren,Xiaobo Liu
Promoted polymerization of Phthalonitrile containing benzoxazine (BA-ph) was designed on basis of the catalysis performance of a type of aniline curing agent (2,6-bis(4-aminophenoxy)benzonitrile (BAB)). The curing processes and curing behaviors of BA-ph with BAB were investigated by differential scanning calorimetry (DSC) and gelatin time. With the assistance of orthogonal test analysis method, main factors that affected the pre-polymerization of BA-ph were studied and the appropriate pre-polymerization conditions were determined. According to the results of dynamic rheological analysis (DRA) and Fourier transform infrared spectroscopy (FTIR), possible curing mechanism of BA-ph with BAB were proposed. The results show that BAB could reduce the prepolymerization temperature of BA-ph resin, and increase its polymerization rate and crosslinking degree, and the BA-ph/BAB polymer mainly formed the aromatic heterocyclic structure of triazine rings, phthalocyanine rings and polyisoindoline rings. Then, thermal stability of BA-ph (BAB15%) polymers pretreated at different temperatures and prepared at 200 °C was analyzed to understand the cross-linked structures. Results indicated that BA-ph (BAB15%) polymers exhibit outstanding thermal properties ( T 5% >410 °C and integral program decomposition temperature ( IPDT ) reached 3342 °C). Mechanical properties and thermomechanical properties of glass fiber reinforced BA-ph composites were also investigated and exhibited excellent mechanical properties, to further reveal the effects of BAB on the polymerization of BA-ph resin and expand the application of high-performance resin-based composites.
研究领域:
材料科学
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高分子化学
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DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2023
·Vol. 47
·期 48
·22269-22275
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IF 3.3
Zilin Fan,Qimeng Ran,Xiaoling Xu,Yin Tang,Xiaobo Liu,Kun Jia
The design of organic precursors with optimized molecular structures is of great importance for improving the fluorescent properties and sensing applications of heteroatom-doped carbon nanodots (CDs). Herein, we designed and synthesized a phthalonitrile derivative containing both melamine and benzoxazine moieties, which has been, for the first time, employed as a cross-linkable precursor to prepare nitrogen-doped carbon nanodots (N-CDs), showing fluorescence emission with a large Stokes shift. As a result of the good affinity between the surface functional groups of N-CD and Ni ions proven by XPS and FTIR techniques, the fluorescence emission of optimized N-CDs can be selectively quenched by Ni ions among other metal ions. Furthermore, the synthesized N-CDs are employed as fluorescent probes for the quantitative detection of Ni ions with a wide concentration range and a high sensitivity (the limit of detection approaching 1.58 nM). Overall, the current work reveals a new possibility for expanding the synthesis route and metal ion sensing of nitrogen-doped CDs.
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DOI
高影响因子
POLYMER
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2021
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IF 4.43
Zhihuan Weng,Lequn Song,Yu Qi,Jiahui Li,Qi Cao,Cheng Liu,Shouhai Zhang,Jinyan Wang,Xigao Jian
Bio-based polymers with better comprehensive properties, showing more competitiveness than their petroleum-based counterparts in high-tech fields is an increasingly trend but also a formidable challenge. In the study, bio-based phthalonitrile precursors were synthesized from natural occurring magnolol derivatives through a highly efficient one step process. Self-curing reactions can be proceeded with allyl groups in the resultant precursors without sacrificing the thermal stabilities of the thermoset resins. The curing behavior, mechanism and processability of the phthalonitrile precursors were studied, and the thermal stabilities of cured polymers were evaluated. Of the two bio-based precursors, the honokiol derivate exhibited a wide processing window of 163 °C with a melting point lower than 70 °C. After curing, both the magnolol- and honokiol-based resins showed glass transition temperature higher than 500 °C and 5% weight loss temperature as high as 527 °C. These properties were superior to those of the petroleum-based reference without allyl group. A model reaction, showed that the curing mechanism of allyl/phthalonitrile system here was considered to be free radical polymerization . The results demonstrate that sustainable magnolol derivatives can be employed as platform chemicals to impart excellent performances to the bio-based polymers for great promise in cutting-edge applications.
研究领域:
材料科学
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化学工程
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有机化学
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DOI
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
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2025
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IF 8.9
Zichun Ding,Jianjian Jiao,Yuhang Wang,Runze Liu,Qing Wang,Jianing Guo,Siying Wang,Lishuai Zong,Xigao Jian,Jinyan Wang
Ultra heat-resistant phthalonitrile resin has faced serious challenges of the trade-off between temperature resistance and toughness and seriously affects its application in the field of temperature resistant structural composites. In this work, a kind of oligo (aryl ethers) containing phenyl-s-triazine and pendent amino group (AFT-Ph/PAFT-Ph) were first selected as modifier co-cured with phthalonitrile prepolymers containing a carborane (CEPN) to achieve synergistic improvement in toughness and heat resistance performance. The flexural and impact strengths of optimized composites reach 278.6 MPa and 58.4 kJ/m 2 , which are increased by 92.7 % and 1091.8 % compared to the blank contrast. The glass transition temperature ( T g ) remained consistent with that of the blank control group, both exceeding 550 ℃. Furthermore, the T d5% –N 2 shows a marginal increase from 706 ℃ in the blank contrast to 713 ℃ in the modified material. Simultaneously conducting research on the mechanism of collaborative improvement mentioned above.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
POLYMER INTERNATIONAL
·
2017
·Vol. 67
·期 3
·322-329
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IF 2.07
Yu Qi,Zhihuan Weng,Jinyan Wang,Shouhai Zhang,Lishuai Zong,Cheng Liu,Xigao Jian
The development of bio-based thermosetting resins with good thermal stability can potentially afford sustainable polymers as replacements for petroleum-based polymers. We report a practical route to a novel catechin-based phthalonitrile resin precursor (CA-Ph), which contains free phenolic hydroxyl groups that result in ‘self-curing’ at elevated temperatures to afford a thermostable polymer. Comparison of the performance of this CA-Ph resin with that of a conventional petroleum-based bisphenol A phthalonitrile resin (BPA-Ph; containing 5 wt% of the curing agent 4,4′-diaminodiphenylsulfone) revealed that CA-Ph exhibits a lower melting point and curing temperature. Cured CA-Ph resin retains 95% of its weight at 520 °C under a nitrogen atmosphere, which compares favorably with results obtained for BPA-Ph resin that retains 95% of its weight at a lower temperature of 484 °C. Kinetic results indicated that the curing reactions of both CA-Ph and BPA-Ph systems follow an autocatalytic mechanism. These results suggest that catechin is a useful bio-based feedstock for the preparation of self-curing and thermally stable phthalonitrile resins for advanced technological applications. © 2017 Society of Chemical Industry
研究领域:
材料科学
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有机化学
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DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
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2020
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IF 4.032
Xian He,Shenjun Liao,Menghao Chen,Renke Li,Yao Liu,Bo Liang,Jianghuai Hu,Ke Zeng,Gang Yang
Tyrosine derived cyclic peptide (TCP) was employed to promote the curing reaction of a phthalonitrile monomer 1,3-bis(3,4-dicyanophenoxy) (3BOCN). Differential scanning calorimetry (DSC) and rheological analysis were used to study the curing behaviors of the TCP/3BOCN blend and confirmed a relatively high curing efficiency. Fourier transform infrared spectrometer (FT-IR) and two-dimensional infrared vibrational echo spectroscopy suggested the cyclic peptide reactive site was responsible for the unique curing behavior. Isoindolin, phthalocyanine and triazine were confirmed as curing products. Thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA) were used to measure the thermal and thermomechanical properties of the cured resin. The results firstly revealed the excellent thermal stability and high glass transition temperature (T g ) of this resin even under a moderate post-curing condition.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
CARBON
·
2019
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IF 7.466
Zhihuan Weng,Kewen Zhang,Yu Qi,Tianpeng Zhang,Miao Xia,Fangyuan Hu,Shouhai Zhang,Cheng Liu,Jinyan Wang,Xigao Jian
Heteroatom-doped hierarchical porous carbons with large specific surface area and high heteroatom content are important but they generally require multistep syntheses and harsh conditions. Herein, a scalable and straightforward strategy is introduced to synthesize N/O co-doped hierarchical porous carbons (DNKs) derived from an all-in-one phthalonitrile precursor 1,3-bis(3,4-dicyanophenoxy)benzene (DPPH) with the assistant of potassium hydroxide and urea. In this facile and template-free method, all the raw materials are placed in the tube furnace, and the one-pot process involves polymerization, carbonization and activation. At 1 bar, ultra-high CO 2 uptake of 7.27 mmol g −1 at 273 K was achieved for the sample DNK@550, which can be attribute to its well-developed micropore structure and abundant nitrogen content (7.93 wt%). Moreover, the distinct features of DNK@650 afforded a high specific capacitance of 487 F g −1 at a current density of 0.1 A g −1 in a three-electrode system using 1 M H 2 SO 4 aqueous as electrolyte. Most importantly, the fabricated symmetric supercapacitor exhibited excellent cycling stability over a new cycle record of 100000 (capacitor retention of ca. 103%). This work provides new insights for the fabrication of versatile porous carbons from readily available and flexible precursors via a facile and scalable route.
研究领域:
材料科学
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能源化学
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纳米技术
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DOI
高影响因子
Polymers
·
2022
·Vol. 14
·期 21
·4700
·
IF 4.967
Xinyang Zhang,Xinyang Wang,Jian Li,Shuo Zhang,Qingxin Zhang,Xiaoyan Yu
A phthalonitrile monomer (DPTP) containing pyridine with sulfide bonds was prepared and cured into polymers using different curing agents under the same temperature-programmed process. We characterized and comprehensively evaluated the effects of different curing agents on the thermal and thermomechanical properties of phthalonitrile resin, showing that the DPTP monomer cured with naphthalene-containing curing agent exhibited the best performance among the three polymers. Differential scanning calorimetric (DSC) investigation manifested that the melting point of the DPTP monomer was 61 °C, with a processing window of about 170 °C, suggesting the presence of a wide processing range. Thermogravimetric analysis (TGA) demonstrated the outstanding heat resistance,T5%, of 460 °C in nitrogen, at the same time demonstrating superior long-term stability compared with other commonly used polymer materials, which proves the long-term usage under high temperatures of 300 °C. Dynamic mechanical analysis (DMA) revealed that the storage modulus at 50 °C was 3315 MPa, and the glass transition temperature (Tg) of the polymer was more than 350 °C. Therefore, DPTP resins have favorable thermal stability as well as prominent thermomechanical properties.Keywords:phthalonitrile resin;processing window;low melting point;long-term stability
研究领域:
材料科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2024
·
IF 2.7
Zhijiao Chen,Cong Peng,Shichao Li,Zhanjun Wu,Tao sun
Phthalonitrile monomer containing oxazine ring (BPS-Ph) was synthesized using bisphenol-S, aniline, paraformaldehyde, and 4-nitrophthalonitrile via a two-step method. The differential scanning calorimetry (DSC) data of the curing process of BPS-Ph monomer indicates that the peak polymerization temperature of the cyan group is about 250°C and that confirms the promoting effect of oxazine ring on the curing reaction of phthalonitrile. The rheological data of E51/DDS containing BPS-Ph indicates that the BPS-Ph monomer also has promoting effect on the curing process. The activation energy was studied via the iso-conversional method principle. The activation energy corresponding to the E51/DDS crosslinking reaction is 75.79 and 60.54 kJ mol −1 , respectively, for pure E51/DDS and E51/DDS/BPS-Ph. Moreover, the activation energy of the crosslinking of phthalhydrazine is 74.1 kJ mol −1 which is rather lower than that in pure BPS-Ph, and that implies the synergistically catalytic effect of the oxazine ring and the amine. The addition of BPS-Ph monomer significantly improves the thermal behaviors of the thermoset. The char yield in N 2 atmosphere increased from 15.6% to 53.9% when adding 30% BPS-Ph to the E51/DDS. Moreover, the peak weight loss temperature decreased from 407 to 385°C. The phase separation size of poly-BPS-Ph in E51/DDS is about tens to hundreds nanometers according to the atomic force microscopy (AFM) phase diagram. It is indicated that incorporation of phthalonitrile monomer containing oxazine ring into epoxy/amine system is an applicable and effective way to promote the thermal behavior of the thermoset.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2024
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IF 4.9
Ao Yang,Pan He,Guangzhao Li,Jiajia Ye,Yumin Huang,Rui Han,Shuai Zhang
Phthalonitrile (PN) resin is a thermosetting resin with excellent properties, but its poor processability hinders its wide application. Meanwhile, as a high-performance green fiber, basalt fiber (BF) shows good overall properties, but the chemical inertness and smooth surface limits its application as well. In this work, a highly reactive organic coating polydopamine (PDA) was used to promote the curing of PN resin and enhance the interfacial interaction between the polymer matrix and the fiber cloth. The successful coating of PDA was verified by SEM observation, FTIR and XPS spectra. It was found that PDA could not only increase the polarity of BF, aid the infiltration of PN resin into the fiber cloth, enhance the interfacial strength, but also promote the consumption of cyano groups and increase the chemical crosslinking density. Consequently, the overall performance of the composites was enhanced. Specifically, the laminate 0.4DABF/BAPh showed flexural strength of 447 MPa and flexural modulus of 23.3 GPa, which was 131 MPa and 4.5 GPa higher than those of BF/BAPh. The glass transition temperature of 0.4DABF/BAPh was also 77 °C higher than that of BF/BAPh.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）