HIGH PERFORMANCE POLYMERS
·
2012
·
IF 0.884
Jie Shen,Xiaolong Li,Ying Zhang,Wenhao Wang,Zushun Xu,Kelvin W. K. Yeung,Ming Xu,Changfeng Yi
A novel fluorinated pyridine-containing aromatic diamine monomer, 4-phenyl-2,6-bis[2-(4-amino-2-trifluoromethyphenoxy)phenyl]pyridine (o, p-6FPAPP), was prepared in a three-step synthetic route. This aromatic diamine was then employed to synthesize a series of fluorinated pyridine-containing polyimides (PIs) by polycondensation with various aromatic dianhydrides via the conventional two-step method. The inherent viscosities of the resulting poly(amic acid)s (PAAs) and PIs were in the range of 0.71–0.89 and 0.62–0.84 dL/g; all the PIs obtained by chemical imidization were readily soluble in common organic solvents such as N, N-dimethylformamide (DMF), N, N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP), dimethyl sulfoxide (DMSO), tetrahydrofuran (THF) and so on. Meanwhile, transparent, strong and flexible PI films were obtained, which had good thermal stability, with the glass transition temperature (Tg) of 195.2°C–232.7°C, the temperature at 10% weight loss of 530.2°C–546.0°C in nitrogen atmosphere, and good optical transparency with the cutoff wavelengths of 354–382 nm, as well as outstanding mechanical properties with tensile strengths of 96.4–105.8 MPa, tensile modulus of 1.57–1.88 GPa and elongations at break of 9.5%–13.4%. The PI films were also found to possess low water uptake of 0.52%–0.67%.
研究领域:
材料科学
·
化学工程
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产品关联
DOI
高影响因子
POLYMER BULLETIN
·
2020
·Vol. 77
·期 12
·6509-6523
·
IF 2.014
Wang Chenyi,Yu Bin,Jiang Cairong,Zhao Xiaoyan,Li Jian,Ren Qiang
A novel aromatic diamine monomer with asymmetric large side group: 4-(2,4,6-trimethyl)phenoxy-1,3-diaminobenzene, was synthesized by a two-step organic reaction. The monomer was separately subjected to a one-step high-temperature polycondensation reaction with three commercial aromatic dianhydrides to obtain a series of polyimides. Their structures and properties were characterized and studied by FTIR, NMR, UV, TGA, DSC, etc. The obtained polyimides showed excellent solubility not only in high-boiling solvents such as NMP, DMAc, and DMF, but also in low-boiling solvents such as CHCl 3 and CH 2 Cl 2 . Their tensile strength was in the range of 76.9–93.5 MPa, the elongation at break was between 4.8% and 7.3%, and the modulus of elasticity was in the range of 1.6–1.8 GPa. The obtained films exhibited good optical transparency, and the representative polyimide derived from 4,4′-oxydiphthalic dianhydride exhibited a light transmittance of more than 83% at a wavelength of 450 nm. Moreover, these polyimides also possessed good thermal properties. Their glass transition temperatures are between 285 °C and 345 °C, and the 10% weight loss temperature in air and nitrogen is above 463 °C, showing excellent thermal properties.
研究领域:
材料科学
·
有机化学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Liyan Chen,Meng Rong,Liangrong Yang,Jiemiao Yu,Hongnan Qu,Qiyu Meng,Shan Ni,Zihao Xu,Xiangyang Zhu,Li Wang,Huifang Xing,Huizhou Liu
The upcycling of Polyurethane (PU) degradation products has been gaining tremendous attention and research interest in recent years. In particular, due to the toxicity to microorganisms, the key process is to remove aromatic diamines selectively and efficiently from the bio-hydrolysate which also includes multiple carboxylic diacids and polyols. Herein, a series of super-hydrophobic hypercrosslinked porous polymers (HCPPs) were prepared to selectively remove aromatic diamines in a neutral condition. They were facially fabricated via Friedel-Crafts alkylation reactions with benzene and three types of benzyl bromides. Besides, the surface area, porous structure, and hydrophobic properties of resulting polymers were adjusted by changing the length and connected nodes numbers of crosslinkers. Particularly, HCPP-TBMB knitted by 1,3,5-tris(bromomethyl)-benzene (TBMB) owned a maximum BET surface area of 1048.8 m 2 g −1 with hierarchical porosity, as well as high thermal stability and super-hydrophobicity. The adsorption experiments on HCPP-TBMB clarified the large adsorption capacities of 2,4-toluene diamine (TDA, 1.062 mmol g −1 ) and 4,4′-methylene dianiline (MDA, 1.971 mmol g −1 ) as well as high selectivity in the model PU hydrolysate. Moreover, thermodynamic experiments and spectral analysis revealed the physical adsorption process for uptake of aromatic diamines on HCPP-TBMB. The main adsorption mechanism contained π-π stacking, hydrophobic interaction, and hole size effect. These findings may provide a promising strategy for highly selective removal of aromatic diamines from the PU bio-hydrolysate.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
Journal of Macromolecular Science Part A-Pure and Applied Chemistry
·
2010
·
IF 0.792
Gang Zhang,Ti-Peng Zhao,Yan-Lun Wang,Sui-Lin Liu,Sheng-Ru Long,Jie Yang
Two kinds of new aromatic diamine monomer containing thio-amide unit, bis[4-(p-aminothiophenyl)benzoyl]diamine (ATPBA), were synthesized by two steps, which was reacted with 1,1′-Ferrocenedicarbonyl Chloride (FCDC) to prepare a new polyamide containing ferrocene and thio-ether unit. The polymers were characterized by FT-IR spectrum, 1H-NMR spectrum, X-ray diffraction, element analyzer, DSC, TGA, SEM, AFM and dissolvability experiment and so on. The intrinsic viscosity of FC-PASAA was 0.42–0.58 dl/g obtained with optimum synthesis conditions. The polymers were found to have excellent thermal performance with glass transition temperature (T
g
) of 229.9–276.8°C, initial degradation temperature (T
d
) of 389.2–391.5°C. They could afford flexible and strong films with tensile strength 66.0–83.9MPa. They showed improved solubility in polar aprotic solvents. They were used to preparing separation membrane successfully.
研究领域:
高分子化学
·
材料科学
·
金属有机化学
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化学合成
·
热分析
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DOI
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2013
·Vol. 31
·期 10
·1359-1371
·
IF 1.27
Zhang Tao,Yan Hong-qiang,Fang Zheng-ping,Peng Mao
Three kinds of novel aromatic diamine-based benzoxazines containing naphthalene, propane-2,2-diyldibenzene and neopentyl groups in the backbone, respectively (designated as BAPNCP, BAPBACP and BAPNPGCP, respectively), were synthesized and characterized. In addition, the effects of backbone structures on curing behaviors of the monomers and thermal and flammability properties of the resulting polymers were systematically studied. The results indicated that BAPNPGCP displayed the highest enthalpy of the curing reaction associated with the ring-opening of benzoxazine, which was due to the effect of benzoxazine ring content per unit mass. Interestingly, the 5 wt% weight loss temperature and char residue after thermogravimetric test for poly(BAPNPGCP) were 8 °C and 7% higher than those of poly(BAPBACP). Meanwhile, the total heat release of poly(BAPNPGCP) was less than half of that for poly(BAPBACP), indicating the substantial effect of benzoxazine ring content on flammability and char formation. Furthermore, it was found that poly(BAPNCP) gave the best thermal stability and flame retardancy, which was due to the synergistic effect between naphthalene group and benzoxazine ring content. This study provides new insight into the curing behavior of benzoxazine and further understanding on the high performance of polybenzoxazine.
研究领域:
材料科学
·
高分子化学
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DOI
高影响因子
Journal of Macromolecular Science Part B-Physics
·
2023
·
IF 1.4
Long-De Wang,Ling Tong,Jian-Wei Wu,Jie-Wu Rong,Li Li
Polyurethaneimide prepolymer was synthesized using the synthesized chromophore C containing tricyanofuran, hexafluorodianhydride and phenyl diisocyanate as monomers. Polyimide prepolymers were synthesized using fluorinated aromatic diether dianhydride and fluorinated aromatic diamine as monomers. Polyurethaneimide-polyimide (PUI-FPI) copolymers were then synthesized by a polycondensation reaction of the polyimide and polyurethaneimide prepolymers. The electro-optic (EO) PUI-FPI copolymers had a special segment structure and concentrate the advantages of polyurethaneimide and polyimide. The copolymers exhibited good film-forming properties, high glass transition temperature (Tg =196 °C), and high thermal stability (Td up to 358 °C). The copolymers possessed a high EO coefficient (γ33 =72 pm/V) at the 1550 nm wavelength, good long-term electro-poled orientation stability, and low optical propagation loss (1.2–1.4 dB/cm) at 1550 nm. Mach-Zehnder interferometric electro-optic modulators were designed and fabricated using the synthesized copolymer as the waveguide material. The prepared polymer optical waveguide EO modulators showed a good low-frequency electro-optic modulation response. The results showed that the synthesized polyurethaneimide-polyimide copolymers meeted the performance requirements for the preparation of polymeric optical waveguide devices and were suitable as polymeric electro-optic waveguide materials.
研究领域:
高分子化学
·
材料科学
·
电光学
·
光波导器件
·
有机电子学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）