COMPOSITES SCIENCE AND TECHNOLOGY
·
2021
·
IF 8.528
Liping Zhou,Yu Tian,Peng Xu,Huijie Wei,Yuhan Li,Hua-Xin Peng,Faxiang Qin
In recent years, the immiscible polymer blend system has attracted much attention as the matrix of nanocomposites . Herein, from the perspective of dynamics, the control of the carbon nanotubes (CNTs) migration aided with the interface of polystyrene (PS) and poly (methyl methacrylate) (PMMA) blends was achieved through a facile melt mixing method. Thus, we revealed a comprehensive relationship between several typical CNTs migrating scenarios and the microwave dielectric properties of their nanocomposites. Based on the unique morphologies and phase domain structures of the immiscible matrix, we further investigated the multiple microwave dielectric relaxation processes and shed new light on the relation between relaxation peak position and the phase domain size distribution. Moreover, by integrating the CNTs interface localization control with the matrix co-continuous structure construction, we found that the interface promotes double percolation effect to achieve conductive percolation at low CNTs loading (~1.06 vol%). Overall, the present study provides a unique nanocomposite material design symphonizing both functional fillers dispersion and location as well as the matrix architecture optimization for microwave applications.
研究领域:
材料科学
·
聚合物纳米复合材料
·
介电性能
·
微波功能材料
✓ 已验证
DOI
高影响因子
Polymers
·
2020
·Vol. 12
·期 10
·2407
·
IF 3.426
Mingjun Niu,Zhongzhou Zhang,Zizhen Wei,Wanjie Wang
Poly(lactic) acid (PLA) is one of the most promising biobased materials, but its inherent flammability limits its applications. A novel flame retardant hexa-(DOPO-hydroxymethylphenoxy-dihydroxybiphenyl)-cyclotriphosphazene (HABP-DOPO) for PLA was prepared by bonding 9,10-dihydro-9-oxy-10-phosphaphenanthrene-10-oxide (DOPO) to cyclotriphosphazene. The morphologies, mechanical properties, thermal stability and burning behaviors of PLA/HABP-DOPO blends were investigated using a scanning electron microscope (SEM), a universal mechanical testing machine, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), limiting oxygen index (LOI), vertical burning (UL-94) and a cone calorimeter test (CCT). The LOI value reached 28.5% and UL-94 could pass V-0 for the PLA blend containing 25 wt% HABP-DOPO. A significant improvement in fire retardant performance was observed for PLA/HABP-DOPO blends. PLA/HABP-DOPO blends exhibited balanced mechanical properties. The flame retardant mechanism of PLA/HABP-DOPO blends was evaluated.Keywords:flame retardant;poly(lactic acid);mechanical properties;blends
研究领域:
材料科学
·
燃烧学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nanomaterials
·
2022
·Vol. 12
·期 9
·1535
·
IF 5.719
Xiaoyu Lin,Yuanying Liang,Zhicheng Hu,Xi Zhang,Youcai Liang,Zhengwei Hu,Fei Huang,Yong Cao
We prepared a series of one-dimensional conjugated-material-based nanofibers with different morphologies and donor/acceptor (D/A) compositions by electrospinning for efficient photocatalytic hydrogen evolution. It was found that homogeneous D/A heterojunction nanofibers can be obtained by electrospinning, and the donor/acceptor ratio can be easily controlled. Compared with the single-component-based nanofibers, the D/A-based nanofibers showed a 34-fold increase in photocatalytic efficiency, attributed to the enhanced exciton dissociation in the nanofibrillar body. In addition, the photocatalytic activity of these nanofibers can be easily optimized by modulating the diameter. The results show that the diameter of the nanofibers can be conveniently controlled by the electrospinning feed rate, and the photocatalytic effect increases with decreasing fiber diameter. Consequently, the nanofibers with the smallest diameter exhibit the most efficient photocatalytic hydrogen evolution, with the highest release rate of 24.38 mmol/(gh). This work provides preliminary evidence of the advantages of the electrospinning strategy in the construction of D/A nanofibers with controlled morphology and donor/acceptor composition, enabling efficient hydrogen evolution.Keywords:photocatalysts;polymer blends;hydrogen evolution
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MOLECULES
·
2023
·Vol. 28
·期 10
·4091
·
IF 4.6
Jia-Yao Chen,Xue-Wen Zhang,Tian-Yu Wu,Hai-Mu Ye
Crystalline/crystalline blends of polymer have shown advantages in the preparation of new polymeric materials. However, the regulation of co-crystallization in a blend is still full of challenges due to the preferential self-crystallization driven by thermodynamics. Here, an inclusion complex approach is proposed to facilitate the co-crystallization between crystalline polymers, because the crystallization process displays a prominent kinetics advantage when polymer chains are released from the inclusion complex. Poly(butylene succinate) (PBS), poly(butylene adipate) (PBA) and urea are chosen to form co-inclusion complexes, where PBS and PBA chains play as isolated guest molecules and urea molecules construct the host channel framework. The coalesced PBS/PBA blends are obtained by fast removing the urea framework and systematically investigated by differential scanning calorimetry, X-ray diffraction, proton nuclear magnetic resonance and Fourier transformation infrared spectrometry. It is demonstrated that PBA chains are co-crystallized into PBS extended-chain crystals in the coalesced blends, while such a phenomenon has not been detected in simply co-solution-blended samples. Though PBA chains could not be totally accommodated in the PBS extended-chain crystals, their co-crystallized content increases with the initial feeding ratio of PBA. Consequently, the melting point of the PBS extended-chain crystal gradually declines from 134.3 °C to 124.2 °C with an increasing PBA content. The PBA chains playing as defects mainly induce lattice expansion along thea-axis. In addition, when the co-crystals are soaked in tetrahydrofuran, some of the PBA chains are extracted out, leading to damage to the correlative PBS extended-chain crystals. This study shows that co-inclusion complexation with small molecules could be an effective way to promote co-crystallization behavior in polymer blends.Keywords:co-crystal;polyester;blend;inclusion complex;thermal property
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MOLECULES
·
2022
·Vol. 27
·期 20
·7086
·
IF 4.927
Xue-Wei Wei,Cong Chen,Tian-Yu Wu,Li-Hai Cai,Hai-Mu Ye
Co-crystallization plays a crucial role in the integration and regulation of thermal and mechanical properties in polymer blends, but the poor compatibility of the components in the crystal phase has always been a major obstacle to co-crystallization, which puts forward stricter requests for linkage and interaction between different entities. On the basis of the hydrogen-bonding interaction that can promote chain stacking and thus improve miscibility, we propose that crystalline/crystalline blends of 2-ureido-4[1H]-pyrimidinone (UPy)-functionalized poly(butylene succinate) and poly(butylene fumarate) (PBS-UPy/PBF-UPy) where UPy groups with quadruple hydrogen-bonding interaction are employed to connect different chain ends, could inhibit phase separation and improve co-crystallization. PBS-UPy/PBF-UPy blends exhibit complex component-dependent and cooling-rate-dependent co-crystallization behavior. A high level of co-crystallization occurs in the range of PBS-UPy-rich fractions, and the proportion could approach over 98% under optimized conditions with the aid of UPy quadruple hydrogen bonds interaction. This work enriches the understanding of co-crystallization in crystalline/crystalline polymer blends and provides more possibility for the design of structures and properties of polymer materials.Keywords:co-crystallization;polymer blend;hydrogen bond;compatibility
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2016
·Vol. 134
·期 5
·
IF 1.866
Yijian Wu,Baoqing Shentu,Zhixue Weng
The SEBS/PP thermoplastic vulcanizates (TPVs) were prepared by melt blending. Di- tert -butyl peroxide (DTBP) was used as the curing agent in combination with trimethylopropane trimethacrylate (TMPTMA) and poly(styrene- b -butadiene-bstyrene) (SBS) as the coagents for the curing process. The synergistic effect of TMPTMA and SBS on the structure and properties of TPVs was studied by means of FT-IR, DSC, torque rheometer, and universal testing machine. Both SEBS and PP crosslinked and the network structure formed under the participation of TMPTMA and SBS. Compared with the sole addition of the coagent, simultaneous loading of both TMPTMA and SBS could provide the TPVs with better solvent-resistance and excellent mechanical properties. The crosslinking mechanism of the TPVs was also proposed. The slight lower value of T m for the TPVs indicated the improved miscibility between PP and SEBS due to the crosslinking reaction. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44392.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2015
·Vol. 132
·期 48
·
IF 1.768
Fei Zhao,Han-Xiong Huang,Shui-Dong Zhang
This work focuses on largely toughening poly(lactic acid)/thermoplastic polyurethane (PLA/TPU) blend with lower content (20 wt %) of TPU using appropriate contents of 4,4-methylene diphenyl diisocyanate (MDI) via simple melt blending. Both scanning electron micrographs and differential scanning calorimetry curves suggest little change of the compatibility between the PLA and TPU phases by adding the MDI. Dynamic rheological test demonstrates that a reaction occurs between the TPU phase and MDI during melt blending. Combining the rheological behaviors and gel contents of the blends, it can be speculated that adding the MDI extends the TPU chains and forms branched and crosslinked structure in the TPU chains sequentially. Toughening mechanism is analyzed and different impact strengths for the blends with different MDI contents are explained based on combined effects of the decreased crystallinities for the PLA matrix and the extended, branched and crosslinked structure in the TPU chains. A 0.8 wt % MDI content is optimal in terms of the impact strength (100.6 kJ/m 2 ) and the elongation at break (392.4%). The former is about 1.9 and 32.5 times of that for the blend without MDI and the PLA, respectively. Moreover, the MDI results in some increase in the tensile strength of the blends. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132 , 42511.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POLYMER RESEARCH
·
2023
·Vol. 30
·期 8
·1-11
·
IF 2.8
Chen Fanfan,Xiao Yao,Yan Sitong,Fang Lin,Wang Zhifen,Liao Jianhe
Modifying natural rubber latex (NRL) and blending it with NRL can improve NRL performance and expand application fields. The performance of co-blended latex will change due to changes in non-rubber components during storage. Therefore, it is important to study the change of properties during the storage of co-blended latexes. In this paper, 30% methyl methacrylate grafted natural rubber (MG30) was synthesized by cumene hydroperoxide/ tetraethylenepentamine (CHPO/TEPA) initiating system, MG30 and NRL were mixed in different proportions to study the morphology and physical and mechanical properties, and the colloidal properties and emulsion properties of co-blended latexes were studied during storage. The results showed that the mechanical stability of NRL and co-blended latexes were high and the viscosity gradually increased during storage. The study of the vulcanization characteristics of the co-blended latexes films and the physical and mechanical properties of the vulcanized latex films showed that the vulcanization time of the co-blended films increased and the torque value increased in comparison to NRL. With the increase of MG30 content, the tensile strength and tear strength of the co-blended latexes vulcanized films showed a trend of increasing and then decreasing, and the co-blended film with 10% MG30 showed the best mechanical properties.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Guozhang Gu,Huaiyang Cai,Yutao Wang,Chen Tang,Guoxiang Zou,Jinchun Li,Rong Yang
Achieving both super toughness and flame retardancy in polylactic acid (PLA) materials hinges on resolving the interface compatibility issues between flame retardants, toughening agents, and PLA, as well as overcoming potential antagonisms between these components. Here, we present an approach employing hyperbranched structures to simultaneously enhance the toughness and flame retardancy of PLA materials. Our strategy involved the reactive blending of PLA with a quaternary bio-based phosphorus-containing copolyester (PPE) featuring side hydroxyl groups and hexamethylene glycidyl cyclotriphosphazene (HGCP). The multi-epoxy groups of HGCP reacted with the hydroxyl and carboxyl groups present in PPE and PLA, resulting in the formation of hyperbranched PLA-PPE copolymers. The hyperbranched copolymers provided great interfacial compatibilization and low viscosity, synergistically promoting the melt-dripping flame-retardant mechanism facilitated by PPE, aiding in the rapid removal of heat and combustible material from the pyrolysis zone. Consequently, the PLA/PPE/HGCP blends exhibited super toughness, achieving a maximum notched impact strength of 70.2 kJ/m 2 . Additionally, the blends demonstrated a 27 % LOI and can pass the UL-94 V-0 rating. Moreover, all the blends are biodegradable in a Proteinase K solution. This research underscores the efficacy of utilizing hyperbranched structures as a promising strategy for the development of PLA materials with simultaneous enhancement of processability, toughness, and flame retardancy.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULES
·
2016
·
IF 5.554
Huarong Nie,Cao Zhang,Yuewen Liu,Aihua He
In this paper, Janus hybrid particles with rubber brushes have been first fabricated by successively grafting polybutadiene chains onto polydivinylbenzene (PDVB) side and polyisoprene chains onto SiO2 side in the case of SiO2@PDVB Janus particles as the template. The weight grafting ratios (Gr) of polybutadiene (PBd) and polyisoprene (PI) brushes were determined as 19.4 and 24.8 wt %, respectively. Such Janus hybrid particles contribute to not only the retardation of phase separation but also the kinetically trapped bicontinuous phase morphology in rubber blends. The interface jamming of these Janus particles supports their promising applications as compatibilizers in polymer blends.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
MACROMOLECULES
·
2017
·
IF 5.835
Dongdong Zhou,Shaoyong Huang,Jingru Sun,Xinchao Bian,Gao Li,Xuesi Chen
The crystallization behaviors and microstructures of poly(l-2-hydroxyl-3-methylbutanoic acid)/poly(l-lactide) blends [P(L-2H3MB)/PLLA] were investigated by OM, DSC, SAXS, in situ temperature-dependent WAXD, and in situ synchrotron WAXS. The blends exhibited a homogeneous state at 250 °C. In the cooling process, P(L-2H3MB), with higher melting temperature, crystallized first at 166.7 °C and drove the formation of the phase separation and microstructure. And the amorphous P(L-2H3MB) and PLLA were excluded into the interlamellar and interfibrillar regions of the former P(L-2H3MB) crystallites. For P(L-2H3MB)/PLLA (5/5), the amorphous P(L-2H3MB) in the interfibrillar regions continued to form crystallites sequentially at 134.6 °C, which clearly confirmed the fractional crystallization of P(L-2H3MB). In our knowledge, this unique fractional crystallization has not been reported yet, of the component in miscible blend, which crystallized first under little confinement. This work provided a new viewpoint and understanding of the relationship between fractional crystallization and microstructures in crystalline/crystalline blends.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER ENGINEERING AND SCIENCE
·
2024
·Vol. 64
·期 7
·2988-3002
·
IF 3.2
Sun Yun,Xuefeng Pan,Feng Zhang,Xuelian He
The cavitation process of high-performance HDPE/UHMWPE blends with a uniform dispersion of UHMWPE during cold stretching was investigated. It was observed that incorporating a small amount of UHMWPE into the HDPE matrix resin can serve as a nucleating agent, increasing the number of contact sites and accelerating the crystallization rate. This leads to the formation of thicker lamellar crystals and tethered molecules, ultimately enhancing the mechanical properties of the HDPE matrix. Furthermore, the relationship between the natural tensile ratio and strain-hardening modulus was confirmed. Microstructural changes within the blends were also explored. As the drawing tangles in the middle, the cavities subsequently evolve by collapsing and merging to align parallel to the tensile direction, culminating in tensile damage forming a large crack in the final macroscopic form. As a result, the presence of more tethered molecules in the later stages of stretching inhibits further cavity growth. Highlights The HDPE/UHMWPE blends were prepared by solution blending and ultrasound-assisted twin-screw extrusion. The mechanisms underlying the formation and evolution of cavities in HDPE/UHMWPE blends, which lead to stress whitening during tensile damage, were examined by using DSC and SAXS/WAXD. The relationship between microstructure and mechanical properties was analyzed by cold-drawing the molded blended sheets at room temperature.
研究领域:
材料科学
·
高分子物理
✓ 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）