JOURNAL OF APPLIED POLYMER SCIENCE
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2019
·Vol. 137
·期 23
·48766
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IF 2.188
Lu Yang,Lequan Wang,Yinghong Chen
The selective laser sintering (SLS) is one of the most important 3D-printing technologies. However, the challenges in SLS could be in the limited high material cost and single material performance. Development of high-performance and multifunctional copowders suitable for SLS is of great importance. Here, polyamide 12 (PA12)/boron nitride (BN) thermal conductive copowders suitable for SLS were successfully prepared through solid state shear milling (S 3 M) technology in combination with cryogenic pulverization technology. The particle size, morphology, grafting reaction between PA12 and BN, rheology behavior, and coalescence behavior of the obtained PA12/BN copowders were carefully investigated. The optimal amount of silica flow additive (0.5 wt %) was determined to achieve the good powder flowability. Under the optimum 3D-printing conditions, the fabrication of parts with high BN loading could be achieved. When BN content was at 40 wt %, the flexural strength could reach 10.6 MPa and the thermal conductivity could reach 0.55 W/m·k, 77% higher than that of pure PA12. After treated with phenolic epoxy resin, the tensile strength and flexural strength of the printed parts with 40 wt % BN loading could reach 14.2 and 25.6 MPa, which were 130 and 115% higher than those of the untreated 3D-printed parts, respectively. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137 , 48766.
研究领域:
材料科学
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复合材料
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3D打印技术
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产品关联
DOI
高影响因子
JOURNAL OF POLYMER ENGINEERING
·
2018
·Vol. 38
·期 10
·933-943
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IF 0.778
Junping Zhou,Ruifang Wang,Xiaojia He,Chunxia Zhao,Haolan Gou,Ling Zhao
The mechanical properties of polybenzoxazine (PBa) resins were improved by adding polyamide 12 (PA12) and modified montmorillonite (OMMT) as additives. The mechanical properties and thermal stability of PBa and resulting PBa composites were investigated using an Instron universal material testing instrument and dynamic mechanical analysis. The morphologies of the fracture surfaces were characterized by scanning electron microscopy. The results of morphological studies showed that PBa/PA12/OMMT composites exhibit significantly improved mechanical properties and thermal stability compared with that of the pristine PBa. When the OMMT content increased to 1 wt%, the fracture toughness (1.36 MPa·m 1/2 ) and the fracture energy ( G IC , 315.76 J·m −2 ) of PBa/PA12/OMMT-1 composites increased by 67.9% and 181.4%, respectively, compared with those of the pristine PBa. The thermal stability properties demonstrated that the storage modulus and glass transition temperature ( T g ) of PBa/PA12/OMMT composites gradually increased with the addition of OMMT particles. The scanning electron microscopy results indicated that PBa/PA12/OMMT composites possess a toughening mechanism of crack deflection, with a large bulk of voids and debonding induced by PA12 and OMMT clay particles. Moreover, the OMMT might provide microvoid nucleating sites at its surface to release constrains for shear yielding.
研究领域:
材料科学
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复合材料
✓ 已验证
产品关联
DOI
高影响因子
Virtual and Physical Prototyping
·
2023
·
IF 10.6
Yanbei Hou,Ming Gao,Jiayao Chen,Wei Shian Tey,Mei Chen,Han Zheng,Boyuan Li,Lihua Zhao,Kun Zhou
Multi jet fusion (MJF), a powder-based additive manufacturing technology, is suitable for fabricating fibre-reinforced polymer composites. However, the types of reinforcement fibres applied in MJF are limited due to the incompatibility between the fibres and polymer. Herein, a simple and cost-effective surface modification method for Fe3O4-coated aramid fibres (Fe3O4@AF hybrids) is proposed to fabricate polyamide 12 (PA12) composites by MJF. The optimal fibre content for Fe3O4@AF/PA12 composites is 6 wt%, which resulted in 10.83% and 16.05% higher ultimate tensile strength and Young’s modulus, respectively, compared with AF/PA12. The addition of Fe3O4@AF hybrids also improved the flame retardancy of AF/PA12 by reducing the peak heat release rate (PHRR) and postponing the temperature at PHRR. This practical surface modification method can be potentially applied to other reinforcement fibres for fabricating functional polymer composites by other powder-based manufacturing technologies.
研究领域:
材料科学
·
制造工程
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产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2021
·
IF 3.764
Kangqiang Gong,Hongchi Tian,Heng Liu,Xueying Liu,Guo-Hua Hu,Bing Yu,Nanying Ning,Ming Tian,Liqun Zhang
Isobutylene–isoprene rubber (IIR)/polyamides 12 (PA12) blends are well known for their high gas barrier property and thus find applications in refrigeration hoses, tire inner liners, and so on. Nevertheless, the design and preparation of a good compatibilizer for the IIR/PA12 blend is required because of the poor compatibility between PA12 and the IIR phases. In this study, an efficient reactive compatibilizer, glycidyl methacrylate (GMA)-grafted IIR (IIR-g-GMA) copolymer, and GMA/styrene (St)-grafted IIR (IIR-g-St-GMA) copolymer were produced through the free-radical melt grafting reaction, which were initiated by dicumyl peroxide (DCP). Compared with IIR-g-GMA, IIR-g-St-GMA shows a significantly higher grafting degree because the fast generated, more stable St-grafted IIR macroradicals can act as a “bridge” to connect GMA molecules on IIR macroradicals. The results indicate that reactive compatibilization occurs by the introduction of the copolymer, and the extent of the interfacial reaction and compatibilization effect increases with increasing the copolymer content and the grafting degree of GMA. Nanomechanical mapping images of atomic force microscopy show that the average interfacial thickness of the blend largely increases from approximately 55 to 120 nm after compatibilization with 30 phr IIR-g-St-GMA. Meanwhile, the size of the IIR dispersed phase domains largely decreases from 3 to 5 μm to approximately 0.7 μm after compatibilization with this copolymer. The compatibilization mechanism of the copolymers on IIR/PA12 blends is discussed.
研究领域:
材料科学
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高分子化学
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工程
✓ 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）