Polymer Chemistry
·
2022
·Vol. 14
·期 5
·573-586
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IF 5.364
Xinjin Yan,Meng Wei,Xu Miao,Xiaoguang Qiao,Xiaomeng Zhang,Peng Fu,Xinchang Pang,Minying Liu,Qingxiang Zhao,Shuang Chen,Zhe Cui
Luminescence of non-conjugated polymers attracts much attention due to its importance in fundamental and applied research. At present, however, the research on nonconventional luminescent polymers (NLPs) in terms of both the structure regulation and emission mechanism seems to be still in its infancy. Herein, we report for the first time that PA1212, a representative engineering plastic with the longest saturated carbon chain among commercial polyamides, is an efficient NLP, which exhibits dual emission of blue fluorescence and persistent room-temperature green phosphorescence as well as high quantum yield (∼13%). Systematic photophysical characterization demonstrates the important role played by hydrogen-bonded amide groups in the emission, and the emission intensity shows a clear linear positive correlation with the amide clusters constructed from ordered hydrogen bonds in the crystalline region. Moreover, PA1212 in the α form with linearly extended hydrogen-bonded clusters exhibits longer emission wavelengths than in the γ form, owing to the narrower band gap between the valence band maximum and the conduction band minimum. Further variable temperature fluorescence studies reconfirm the amide cluster-triggered emission (CTE) mechanism of PA1212, and show the possibility of application of fluorescence spectra in the study of polyamide aggregation states. This work not only deepens the understanding of CTE, but also provides a new strategy to regulate the luminescence of polyamides, and meanwhile, highlights the application prospects of luminescent polyamides.
研究领域:
材料科学
·
光物理学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS & DESIGN
·
2014
·
IF 3.171
Ziqing Cai,Xiaoyu Meng,Haimu Ye,Chuanbo Cong,Yufeng Wang,Lishan Cui,Qiong Zhou
In this study, the mechanical properties and structure orientation of pure polyamide 1212 (PA1212) were compared with those of PA1212–carbon nanofibers (CNFs) nanocomposites. The tensile strength of the composite containing 0.3 wt.% modified CNFs was improved from 328 MPa (pure PA1212) to 373 MPa after drawing. The reinforcing effect was investigated in terms of crystallization behavior, crystal morphology, alignment of CNFs, and crystal orientation degree. Spherulites developed into oriented crystals after drawing, and the CNFs aligned along the drawing direction. The heterogeneous nucleation effect of the aligned CNFs improved the crystal orientation degree, which produced the reinforcing effect. The oriented fibril structures with rigid nanofibers acting as nuclei reinforced the entire oriented crystals in the composites.
研究领域:
材料科学
·
复合材料
✓ 已验证
产品关联
DOI
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
·
2020
·
IF 3.333
Feifei Ji,Peng Fu,Shangyun Wang,Tong Liu,Lingling Lv,Xinyu Guan,Xiaomeng Zhang,Haitao Zhao,Xiaoguang Qiao,Xinchang Pang,Minying Liu,Qingxiang Zhao,Zhe Cui
Although polyamide- co -polyether, the most important co-polyamide species, has achieved big success, the inadequate biocompatibility still restricts it further application in biomedical area. In this paper, polydimethylsiloxane (PDMS) segment is introduced into copolymer to replace polyether segment, which is intended to fulfill the copolymer with improved surface performance. Two prepolymer condensation process was used to synthesis the novel PA1212- b -PDMS series, which is constructed by PDMS flexible segment (M n = 1000 g/mol) and PA1212 rigid segment (M n = 1000, 3000, 5000, 7000, 10,000 g/mol). FTIR and 1 H NMR were carried out to evidence the success of the copolymerization and verify the chemical structure . Melting and crystallization behavior , thermal stability, and crystal structure of the series were characterized by DSC , TG and XRD , respectively. To explore the potential usage of the copolymers, mechanical properties were thoroughly investigated. The series possess tunable toughness and rigidity corresponding to different chain compositions . When M n of PA1212 segment is above 5000 g/mol, the copolymer presents typical tough and stiff feature with an ultimate elongation rate of around 500% and a fair tensile strength around 35 MPa. More than that, the platelet adhesion and activation test was conducted to estimate the biocompatibility of the polymers. The contact angel goniometry and XPS were further utilized to understand their surface performance. The as-prepared copolymers give distinct-different performance from homo-polyamide and polyamide- co -polyether. Barely cell adhesion on the surface indicates the greatly improved biocompatibility achieved by the series, which promises the mechanical-property-adjustable novel co -polyamide a broad prospect in biomedical area.
研究领域:
材料科学
·
生物医学工程
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DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2014
·Vol. 132
·期 6
·
IF 1.64
Ziqing Cai,Xiaoyu Meng,Xiaocan Zhang,Lishan Cui,Qiong Zhou
In this study, the effects of carbon nanofiber (CNF) surface modification on mechanical properties of polyamide 1212 (PA1212)/CNFs composites were investigated. CNFs grafted with ethylenediamine (CNF- g -EDA), and CNFs grafted with polyethyleneimine (CNF- g -PEI) were prepared and characterized. The mechanical properties of the PA1212/CNFs composites were reinforced efficiently with addition of 0.3 wt % modified CNFs after drawing. The reinforcing effect of the drawn composites was investigated in terms of interfacial interaction, crystal orientation, crystallization properties and so on. After the surface modification of CNFs, the interfacial adhesion and dispersion of CNFs in PA1212 matrix were improved, especially for CNF- g -PEI. The improved interfacial adhesion and dispersion of CNFs in PA1212 matrix was beneficial to reinforcement of the composites. Compared with pure PA1212, improved degree of crystal orientation in the PA1212/CNF- g -PEI (CNF- g -EDA) composites was responsible for reinforcement of mechanical properties after drawing. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132 , 41424.
研究领域:
材料科学
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高分子化学
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产品关联
DOI
高影响因子
MACROMOLECULAR SYMPOSIA
·
2025
·Vol. 414
·期 4
·e70085
·
IF 0
Chenjun Zhang,Xi Zhang,Xiaodan Liu,Yiheng Li,Xiaoqi Wang,Xu Jin,Man Shen,Lanqiong Zhang
Specialty engineering rubber has been put forward with more stringent requirements. In this paper, the material properties and reinforcing effects of several fillers were investigated, and polyamide was selected as the target reinforcing material to modify hydrogenated nitrile butadiene rubber (HNBR) in order to improve the temperature resistance of the system. It was concluded that the mechanical properties of PA1212/HNBR system were better than those of PC/HNBR system at 120°C. The optimum PA1212 additive amount was determined through the mechanical property test and dispersion state observation of the blended system, which proved that the PA1212 reinforcing system significantly improved the heat resistance and mechanical properties of HNBR. The modified HNBR has excellent tensile strength and elasticity, which effectively improves the reliability and service life of the sealing equipment under high temperature conditions, and provides experimental references and theoretical basis for the research and development of high-temperature resistant rubber.
研究领域:
材料科学
·
高分子科学
·
机械工程
·
化学工程
✓ 已验证
产品关联
DOI
危险品化学品经营许可证（带存储）