Polymers
·
2024
·Vol. 16
·期 8
·1176
·
IF 4.7
Diansong Gan,Yuejun Liu,Tianhui Hu,Shuhong Fan,Lingna Cui,Guangkai Liao,Zhenyan Xie,Xiaoyu Zhu,Kejian Yang
The biaxially-oriented PA56/512 has excellent mechanical strength, extensibility and water–oxygen barrier properties and has broad application prospects in green packaging, lithium battery diaphragm and medical equipment materials. The correlation between the aggregation structure evolution and macroscopic comprehensive properties of copolymer PA56/512 under biaxial stretching has been demonstrated in this work. The structure of the random copolymerization sequence was characterized by13C Nuclear magnetic resonance (NMR). The typical isodimorphism behavior of the co-crystallization system of PA56/512 and its BOPA-56/512 films was revealed by differential scanning calorimetry (DSC) and X-ray diffraction (XRD) tests. And the aggregation structure, including the hydrogen bond arrangement, crystal structure and crystal morphology of PA56/512 before and after biaxial stretching, was investigated by XRD, Fourier-transform infrared spectroscopy (FTIR) and polarized optical microscopy (POM) tests. Furthermore, the effect of the biaxially-oriented stretching process on the mechanical properties of PA56/512 has been demonstrated. In addition, a deep insight into the influence of the structure on the crystallization process and physical–mechanical performance has been presented. The lowest melting point at a 512 content of 60 mol% is regarded as a “eutectic” point of the isodimorphism system. Due to the high disorder of the structural units in the polymer chain, the transition degree of the folded chain (gauche conformation) is relatively lowest when it is straightened to form an extended chain (trans conformation) during biaxially-oriented stretching, and part of the folded chain can be retained. This explains why biaxially stretched PA56/512 has high strength, outstanding toughness and excellent barrier properties at the pseudo-eutectic point. In this study, using the unique multi-scale aggregation structure characteristics of a heterohomodymite polyamide at the pseudo-eutectic point, combined with the new material design scheme and the idea of biaxial-stretching processing, a new idea for customized design of high-performance multifunctional polyamide synthetic materials is provided.
研究领域:
材料科学
·
高分子化学
·
生物材料
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2024
·
IF 8.4
Zhuoqun Li,Guangshun Dong,Jian Pan,Xinyu Chen,Xinyu Lou,Lilan Huang,Kai Guo
With the continuous development of environmental protection and resource recycling demands, the development of bio-based separation membrane materials has increasingly attracted attention. Bio-based polyamide 56 (PA56), exhibiting excellent hydrophilicity, spinnability, and mechanical properties, is expected to complement and replace traditional separation membrane materials. In this study, the electrospinning preparation and structural control of PA56 nanofiber membranes were achieved through the optimization of PA56 content and mixed solvent ratios. The study found that when the PA56 content was 16 wt% and the formic acid to acetone ratio in the mixed solvent was 8:2, the nanofiber diameter distribution was the most uniform. Building on this, amino-functionalized modified silica (SiO 2 –NH 2 ) nanoparticles were introduced to prepare PA56/SiO 2 –NH 2 composite nanofiber membranes featuring a cobweb-like nanofiber network and micro-nodule structure. The effects of the addition of SiO 2 –NH 2 nanoparticles on the morphology, structure, and properties of the fiber membranes were studied. The results indicate that the control of the mixed solvent ratio and the addition of SiO 2 –NH 2 nanoparticles led to the formation of a cobweb-like nanofiber network and micro-nano nodular structure on the nanofiber surface, enhancing the hydrophilicity of PA56 nanofiber membranes. The M − 3 membrane with a nanoparticle addition amount of 0.8 wt% exhibited high hydrophilicity and underwater superoleophobic properties, achieving efficient separation of stable oil-in-water emulsions with a separation efficiency of 99.8 %. This work provides a new bio-based membrane material and its preparation method for treating oily wastewater using the membrane separation method.
研究领域:
材料科学
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环境科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2025
·
IF 9
Guangshun Dong,Zhuoqun Li,Jian Pan,Xinyu Chen,Xinyu Lou,Fulai Zhao,Yao Sun
With the development of industrialization, the discharge of oily wastewater has been increasing significantly. In this study, a novel bio-based oil–water separation membrane was developed using bio-based Polyamide 56 (PA56) as the matrix material, which was modified by incorporating hydroxylated boron nitride nanosheets (BNNS-OH) through a blending approach. The PA56/BNNS-OH composite nanofiber membrane was fabricated via electrospinning. The impact of adding BNNS-OH on the morphological structure, selective permeability, and oil–water separation performance of the composite nanofiber membrane was explored. The results showed that, the introduction of BNNS-OH increased the surface roughness of the nanofiber membrane, forming a micro-nano nodular structure. This not only significantly enhanced the membrane’s hydrophilicity but also endowed it with outstanding underwater superoleophobicity. The M−3 membrane, prepared with 5 wt% BNNS-OH relative to PA56 content, exhibited superhydrophilic/underwater superoleophobic properties. It demonstrated efficient separation performance for various types of surfactant-stabilized emulsions (SSEs), with a separation efficiency of 99.84% for n-hexane-based SSE, approaching complete separation. Moreover, the membrane exhibited excellent cycling and thermal stability, chemical resistance, and self-cleaning properties under complex conditions. This study provides new insights and methods for developing novel bio-based and environmentally friendly oil–water separation membranes, which hold significant potential for application in oily wastewater treatment.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
·
2025
·
IF 9.8
Yuxin Wei,Menglong Dai,Yige Liu,Rui Hao,Shuchang Wang,Huiqun Zeng,Xinghua Hong
Biobased multifunctional composites with graphene-like fillers can be widely used in various industries, such as aerospace, automotive, and energy industries. Such organic‒inorganic composites containing biomaterials currently suffer from prolonged fabrication processes and limited functionality. Herein, a biobased composite that incorporates in situ reduced graphene oxide (RGO) onto a carbon fiber mat (CFM) is presented, which is rapidly combined with biobased polyamide (PA56) under high-temperature and low-pressure conditions to maintain the structural integrity of the three-dimensional network within the matrix, thereby enhancing its electrical and mechanical properties. As a result of these strategies, the biobased RGO/CFM/PA56 composite demonstrates significantly enhanced electrical heating performance (5 V, 126 °C) and electromagnetic shielding capability (76 dB, 0.74 mm), which is among the highest values reported for existing biobased composite materials. Furthermore, the material exhibited notable thermoelectric properties, characterized by a value of −25.3 μV K −1 . Notably, the modified composite demonstrates rapid thermal forming capabilities and possesses welding characteristics facilitated by PA56, enabling it to be recyclable and reusable. After rapid repair, the mechanical performance of the samples remains at approximately 80 %, whereas the other functionalities are maintained above 90 %. This study is the first to report biobased PA56/carbon fiber mat composites, highlighting their benefits in various applications and providing a fresh perspective on sustainable and high-performance biobased composites.
研究领域:
材料科学
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高分子科学
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纳米技术
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复合材料工程
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可持续技术
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电磁工程
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2023
·Vol. 15
·期 10
·2345
·
IF 5
Diansong Gan,Yuejun Liu,Tianhui Hu,Shuhong Fan,Xiaochao Liu,Lingna Cui,Ling Yang,Yincai Wu,Lily Chen,Zhixiang Mo
A new bio-based polyamide 56/512 (PA56/512) has been synthesized with a higher bio-based composition compared to industrialized bio-based PA56, which is considered a lower carbon emission bio-based nylon. In this paper, the one-step approach of copolymerizing PA56 units with PA512 units using melt polymerization has been investigated. The structure of the copolymer PA56/512 was characterized using Fourier-transform infrared spectroscopy (FTIR) and Proton nuclear magnetic resonance (1H NMR). Other measurement methods, including relative viscosity tests, amine end group measurement, thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), were used to analyze the physical and thermal properties of the PA56/512. Furthermore, the non-isothermal crystallization behaviors of PA56/512 have been investigated with the analytical model of Mo’s method and the Kissinger method. The melting point of copolymer PA56/512 exhibited a eutectic point at 60 mol% of 512 corresponding to the typical isodimorphism behavior, and the crystallization ability of PA56/512 also displayed a similar tendency.Keywords:copolymer PA56/512;bio-based polymer;thermal properties;non-isothermal crystallization kinetics
研究领域:
材料科学
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高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MACROMOLECULAR RAPID COMMUNICATIONS
·
2023
·Vol. 44
·期 24
·2300371
·
IF 4.6
Shikun Zhao,Shun Gong,Biao Zhao,Like Hou,Lurong Zhang,Qing Hu,Kai Pan
Polyamide 56 (PA56) has gained significant attention in the academic field due to its remarkable mechanical and thermal properties as a highly efficient and versatile biobased material. Its superior moisture absorption property also makes it a unique advantage in the realm of fiber textiles. However, despite extensive investigations on PA56's molecular and aggregate state structure, as well as processing modifications, little attention has been paid to its polymerization mechanism. Herein, the influence of temperature and time on PA56's polycondensation reaction is detailed studied by end-group titration and carbon nuclear magnetic resonance (NMR) techniques. The reaction kinetics equations for the pre-polymerization and vacuum melt-polymerization stages of PA56 are established, and possible side reactions during the polycondensation process are analyzed. By optimizing the reaction process based on kinetic characteristics, PA56 resin with superior comprehensive properties (melting temperature of 252.6 °C, degradation temperature of 371.6 °C, and tensile strength of 75 MPa) is obtained. The findings provide theoretical support for the industrial production of high-quality biobased PA56.
研究领域:
材料科学
·
化学工程
·
高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）