JOURNAL OF MATERIALS SCIENCE
·
2019
·Vol. 54
·期 18
·11804-11817
·
IF 3.442
Fu Rao,Dong Congcong,Zhang Yu,Sun Changmei,Qu Rongjun,Ji Chunnuan,Zhang Ying
Multiwalled carbon nanotubes (MWNTs) are fillers of choice for composite reinforcement owing to their outstanding modulus and strength. However, the poor dispersion and load transfer between MWNTs and matrix still limit their potential and further application of MWNTs in mechanical reinforcement. In this paper, we report a facile “one-pot” method for functionalization of MWNTs with PPTA-oligomer (o-PPTA). The obtained o-PPTA functionalized multiwalled carbon nanotubes (MWNTs/o-PPTA) can be well dispersed in DMF solvent. Polyvinyl chloride (PVC) was chosen as a model polymer for investigating the reinforcement effect of MWNTs/o-PPTA. The results of tensile tests illustrated that the Young’s modulus, toughness and yield strength of composite films were obviously improved compared to those of neat PVC film, which were increased by 129%, 262% and 126%, respectively. The factors including molecular weight of loaded o-PPTA and dosage of MWNTs/o-PPTA on PVC reinforcement effect were also studied. The results showed that MWNTs/o-PPTA is promising additive for reinforcing PVC.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
JOURNAL OF POLYMER RESEARCH
·
2015
·Vol. 22
·期 2
·1-14
·
IF 1.92
Li Hongbin,Shi Wenying,Zhang Yufeng,Zhou Rong
Poly( p -phenylene terephtalamide) (PPTA) reinforcing blends are of great scientific interest, however the thermodynamic difference of the components make them incompatible with inferior physical-chemical properties. In this work, with the aim of exploring novel separation membrane materials, PPTA/poly(vinylidene fluoride) (PVDF) reinforcing blends were prepared by a novel reactive blending technique of in situ polymerization (method І), and the conventional solution blending (method Π), respectively. The effects of these two methods on polymers compatibility were investigated and compared through ATR-FTIR, XRD, XPS and FESEM characterization. Thermal stability, surface hydrophilicity and mechanical properties were measured through TG, water contact angle (WCA) and tensile measurements. It was found that stronger intermolecular interaction especially hydrogen bonds between polymer components in in-situ blends prevented PVDF from crystallization and a continuous phase configuration appeared. However, slution blends showed an obvious two-phase structure in FESEM observation which varied from a spherical crystallization of PVDF at low PPTA content to a fibrous-like crystallization of PPTA at high PPTA concentration. Solution blends showed lower hydrophilicity which was attributed to the PPTA crystallization and its perpendicular uniplanar orientation along blend film surface. In-situ blends exhibited higher tensile strength which was due to the better polymers compatibility between the rigid reinforced PPTA molecules and flexible PVDF matrix. The PPTA/PVDF in-situ blend is a promising candidate for the high-performance separation membrane material.
研究领域:
材料科学
·
高分子化学
·
膜技术
✓ 已验证
产品关联
DOI
高影响因子
IRANIAN POLYMER JOURNAL
·
2023
·Vol. 32
·期 8
·979-990
·
IF 3.1
Fu Mengjie,Wang Chun,Lai Xing,Xiao Changfa,Ding Ying
In terms of nanofiltration (NF) membrane development, the properties of membrane substrates and thin-film composite (TFC) structures have become an important factor to determine the separation performances of NF membrane. In this paper, the method of interfacial polymerization assisted by spacer spraying was used to construct the striped structure at nanometer scale. Nanoscale striped structure was prepared successfully on PPTA (poly( p -phenylene terephthamide)) NF surface with 1.3 g/L of UiO-66-NH 2 in the aqueous phase, and the morphology gradually changed to “point shaped” structure when 2.6 g/L of UiO-66-NH 2 in the aqueous phase. The optimized PPTA/UiO-66-NH 2 NF (PU4) membranes were used for dye/salt separation of methylene blue (MB). Compared with the nascent PPTA NF membranes, it showed a higher MB rejection rate of 98.6%, along with permeation flux of 19.79 L/m 2 \(\cdot\) h \(\cdot\) MPa. The salt separation order of the PU4 membrane was Na 2 SO 4 > MgSO 4 > MgCl 2 > NaCl. The rejection rates were 96.3%, 85.4%, 53.2%, and 18.4%, respectively. Under strong acid and alkali conditions, the separation performance was rejected 86.5%, better under alkaline conditions. More importantly, after a six-time recycle, the PU4 membrane showed no significant change in separation performance, suggesting its excellent stability. The novel strategy in this study provided an approach to develop advanced UiO-66-NH 2 membranes toward sustainable molecular separation in environmental applications. Graphical abstract
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Water Process Engineering
·
2024
·
IF 6.3
Jialin Wei,Zhiyuan Qiao,Dinghe Yan,Jingwen Chu,Xinyi Zheng,Dawei Ji,Changfa Xiao,Chun Wang
In this study, we deposited polyelectrolyte multilayers (PEMs) on Poly ( p -phenylene terephthamide) (PPTA) ultrafiltration (UF) substrates with strong polyelectrolytes (PEs): polystyrene sulfonic acid (PSS) and poly (diallyldimethylammonium chloride) (PDADMAC). The growth pattern of PEMs was shifted from linear to exponential by changing substrate potential, which was attributed to synergism and antagonism of dispersion of PEs on hydrophilic substrates and electrostatic interaction between PEs and substrates. Eventually, PEMs of layer-dominated and pore-dominated regimes were successfully obtained. We focused on the transition from the pore-dominated to the layer-dominated regime of PEMs. The PEMs nanofiltration (NF) membranes in this situation showed a better separation performance due to the together work of the interface and in-pore energy barriers. The retention rate of Na 2 SO 4 and MgSO 4 was 98 % and 91 %. The eosin Y retention rate was 99.9 % and only declined 2 % after 100 h. The hindered deposition of pore-dominated regimes led to denser and thinner layers, which achieved long-term acid resistance. It maintained a stable salt retention after 185 h cross-filtration of 0.1 M H 2 SO 4 feed solution. The performance of PEMs NF membrane was improved from a new perspective, and excellent acid-resistant nanofiltration membranes were obtained, which are expected to be used to treat industrial acidic wastewater.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2023
·Vol. 140
·期 44
·e54607
·
IF 3
Zhiping Zhao,Xiangjun Gong,Changmei Sun,Ying Zhang,Rongjun Qu,Ying Wang
In this article, Styrene butadiene rubber/poly-p-phenylene terephthamide (SBR/PPTA) nanocomposite was synthesized via in-situ interfacial polycondensation of para-phenylenediamine (PPD) and para-benzoyl chloride (TPC) between the interface of SBR-containing cyclohexanone (CYC) solution and water. Fourier transform-infrared spectroscopy (FTIR) and x-ray diffraction (XRD) confirmed the formation of PPTA in SBR matrix. Transmission electron microscopy (TEM) indicated PPTA nanosheets were uniformly dispersed in the SBR matrix. The thermal stability and mechanical properties of SBR/PPTA nanocomposite were also studied. Results showed that PPTA significantly improved the mechanical properties and thermal stability of SBR. The tensile strength and 200% tensile stress of SBR/PPTA-3 were 120.9% and 150.8% higher than those of Pure rubber, respectively. The tensile strength and elongation at break of SBR/ PPTA-3-30% were 187.2% and 36.9% higher than those of Pure rubber, enabling promising applications of this new composite rubber material.
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 Environmental Chemical Engineering
·
2025
·
IF 7.2
Jingwen Chu,Dinghe Yan,Zhiyuan Qiao,Feng Xu,Yang Ye,Jialin Wei,Dawei Ji,Haolong Xue,Shiqiang Song,Changfa Xiao,Jingjing Yan,Chun Wang
Using a porous ultrafiltration membrane made of poly(terephthalamide) (PPTA) as the base membrane, and using poly (allylamine hydrochloride) (PAH) and poly (styrene sulfonate) (PSS) respectively as the polycation and polyanion, a PPTA/PEMs multilayer membrane was prepared via the layer-by-layer (LBL) assembly method. Subsequently, polypyrrole (PPy) as a conductive separation layer was in situ polymerized on the surface of the PPTA/PEMs multilayer membrane using pyrrole (Py) and ferric chloride (FeCl 3 ) as the reactant and activating initiator, respectively, through chemical vapor deposition (CVD). By directing the control of the number of PEMs charged layers and their charge properties, a PPTA/PEMs/PPy composite nanofiltration membrane with stable and controllable interlayer structure was prepared. Further, the surface microstructure, chemical composition, hydrophilicity, and surface charge of the PPTA base membrane and the PPTA/PEMs/PPy composite nanofiltration membrane were characterized using SEM, AFM, FTIR, water contact angle, and zeta potential measurements. The results showed that when the number of polyelectrolyte layers was three (PAH/PSS) 3 , the PPTA/PEMs/PPy composite nanofiltration membrane exhibited high desalination performance and good permeability under a transmembrane pressure of 0.8 MPa. Subsequently, its structural performance stability was investigated under high-temperature (20°C and 80°C), acidic (pH=2), and alkaline (pH=13) conditions. After 10 hours of testing, the permeability of the PPTA/PEMs/PPy composite nanofiltration membrane for a 5 g/L Na 2 SO 4 solution decreased slightly, but the rejection rate remained almost stable. Compared to the PPTA/PPy composite nanofiltration membrane from previous studies, the PPTA/PEMs/PPy composite nanofiltration membrane obtained in this study showed improved permeability and rejection rate in high-concentration saline wastewater, with good thermal stability and chemical corrosion resistance. This provides guidance for the application of nanofiltration membranes in the treatment of saline wastewater under harsh conditions.
研究领域:
材料科学
·
环境工程
·
膜技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2023
·Vol. 141
·期 10
·e55050
·
IF 3
Yang Mo,Gang Hu,Yuanyuan Gao,Mao Zhang,Ruijin Liao
This study investigates the effect of 1,2,3,4-butane tetracarboxylic acid (BTCA) crosslinking treatment on the electrical properties of poly-p-phenylene terephthalate (PPTA)/cellulose insulation paper to prepare a novel composite insulation paper with low dielectric constant and good electrical performance. Three-layer PPTA/cellulose composite paper crosslinked by BTCA under various conditions, composite paper without crosslinking, directly mixed composite paper, and conventional Kraft paper are prepared. The morphology and surface chemical composition of the paper samples are characterized. Dielectric, mechanical, and thermal properties are investigated. Results show that the BTCA concentration of 0.2 mol L −1 with a 180°C curing temperature is the relatively superior crosslinking condition to prepare a novel composite with low dielectric constant and good comprehensive performance. The dielectric constant and loss of the novel composite paper decrease to 3.21 and 0.392 at 50 Hz. The tensile strength of the BTCA crosslinked three-layer PPTA/cellulose composite paper (thickness: 130 μm) has reached 10.01 kN m −1 , increased by 41.6% than the directly mixed composite paper. The novel BTCA crosslinked composite paper also shows improved thermal stability. The BTCA crosslinking proves to be a promising method to improve the dielectric properties and electrical performance of the PPTA/cellulose composite paper.
研究领域:
材料科学
·
电气工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2015
·
IF 2.711
Hongbin Li,Wenying Shi,Yufeng Zhang,Rong Zhou,Haixia Zhang
High modulus poly( p -phenylene terephtalamide) (PPTA) reinforced composites are of great scientific interests. But the thermodynamic difference makes the polymer pairs incompatible and endows the composites with inferior physical-chemical properties. In this study, hydrophilic poly(vinylidene fluoride) (PVDF)/poly( p -phenylene terephtalamide) (PPTA) blend membrane with improved hydrophilicity and mechanical strength was prepared through in situ polycondensation of p -phenylene diamine (PPD) and terephthaloyl chloride (TPC) in PVDF solution and subsequent immersion precipitation phase inversion process. The effects of PPTA concentration in polymer dopes on membrane formation process, structure, morphology and performance were systematically investigated. The results showed that thermodynamically, PPTA acted as a demixing enhancer which accelerated the phase inversion process. Dynamically, liquid-liquid phase separation was still in control of membrane formation process especially in the later period, whereas the addition of PPTA mainly promoted the early emergence of the liquid-liquid demixing. The surface hydrophilicity, ant-fouling properties and mechanical strength were significantly improved when PPTA content was 17 wt%. When PPTA content increased to 26 wt%, membrane bursting pressure increased to nearly 0.6 MPa which was 1.5 times higher than that of PVDF membrane. The resultant PVDF/PPTA blend membrane exhibited an improved antifouling property than that of PVDF membrane when applied in the MBR in the treatment of landfill leachate and also showed a relatively high removal rate of chemical oxygen demand (COD) and chrom.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
DESALINATION
·
2024
·
IF 8.3
Jialin Wei,Dinghe Yan,Zhiyuan Qiao,Jingwen Chu,Dawei Ji,Changfa Xiao,Chun Wang
It produces a large number of organic brine during the polymerization process of Kevlar®, which contains N-(1-Methyl-2-pyrrolidinone) (NMP) and high concentrations of CaCl 2 and NaCl. The wastewater will cause serious pollution of water and soil resources if discharged directly. The separation and recycling of inorganic salts have been an industrial difficulty. In this paper, based on the novel concept of green self-recycling, we used Poly ( p -phenylene terephthamide) (PPTA, resin of Kevlar®) ultrafiltration membrane as the substrate, composited the loose and curled polyelectrolyte multilayers (PEMs) as interlayers and formed a homogeneous polyamide separation layer through interfacial polymerization, from which we obtained the homogeneous reinforcement aramid composite nanofiltration (NF) membrane. The composite NF membranes with different interlayer numbers showed different advantages. For single-component brine, the retentions of PEMs-1/PA membrane were 93 % and 98.4 % for 10 g/L CaCl 2 and MgSO 4 respectively. For mixed brine of 20 g/L CaCl 2 and NaCl, the retentions of PEMs-3/PA membrane were 87.13 % and 1.05 % for CaCl 2 and NaCl respectively with the separation factor as high as 82.95. In the test of long-term service stability, PEMs-3/PA maintained stable performance in 4 cycles total of 160 h. And the permeance could almost fully recover after pure water backwash of only 0.5 h. In addition, the structural stability and anti-scaling performance of the PEMs-3/PA membrane were further verified in high-temperature brine. Surprisingly, the obtained PPTA NF membrane in this work could effectively treat the high-saline brine in the Kevlar® polymerization process and would have more promising prospects in the treatment of industrial wastewater of brine.
研究领域:
材料科学
·
环境工程
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
·
2025
·
IF 8.9
Fengdong Teng,Ying Yuan,Na Li,Shubin Song,Junrong Yu,Yan Wang,Zuming Hu
The synergistic integration of mechanical robustness with multifunctionality remains a critical challenge in flexible shielding materials. Here, a molecular engineering strategy using para -aramid (PPTA) prepolymers as reactive monomers in an NMP/CaCl 2 composite solvent system was introduced, through which high-molecular-weight PPTA (HMW-PPTA) solutions with an inherent viscosity of 4.1 dL·g −1 were synthesized via controlled secondary polymerization. Scalable blade-coating synergized with molecular assembly enabled rapid processing of these solutions into films exhibiting a tensile strength of 278.5 MPa, elongation at break of 14.3 %, and toughness of 23.5 MJ·m −3 . Hydrogen-bond-mediated in situ polymerization of conductive polypyrrole (PPy) on PPTA substrates yielded multifunctional PPTA-PPy (PAP) composite films. Dynamic interfacial interactions and nanoparticle-enabled defect repair synergistically enhanced the tensile strength and toughness of the optimized PAP (PAP-15) films to 311.4 MPa and 32.4 MJ·m −3 , respectively, alongside a high electrical conductivity of 1510 S·m −1 . Leveraging this conductivity, PAP-15 films achieve multifunctional integration, including 28.3 dB (8201 dB·cm 2 ·g −1 ) electromagnetic interference shielding effectiveness in the X-band, rapid Joule heating to 134 ℃ within 10 s at 5 V, and self-extinguishing behavior. This work establishes a universal platform for scalable production of high-performance PPTA-based flexible composites, overcoming traditional mechanical-functional trade-offs in shielding materials.
研究领域:
材料科学
·
高分子化学
·
纳米技术
·
电磁屏蔽
·
柔性电子
✓ 已验证
产品关联
DOI
高影响因子
Journal of Water Process Engineering
·
2022
·
IF 7.34
Xing Lai,Chun Wang,Liming Wang,Changfa Xiao
In this study, a stable and controllable poly( p -phenylene terephthamide)/polypyrrole (PPTA/PPy) composite organic solvent nanofiltration (OSN) hollow fiber membrane was successfully prepared based on the robust chemical vapor deposition (CVD) method. The structure and properties of the prepared PPTA/PPy OSN membranes were studied in detail. Interestingly, after modifying by PPy, SEM showed that the surface of the membrane formed a layer of “Turing-like” structure and evenly covered the surface of the membrane. It was evident that the prepared PPTA/PPy OSN membranes achieved good dye-removal ability with a molecular weight cut-off range from 200 to1000 Da, and the rejection of negative dyes was higher than 93.4%. Especially at high temperature (80 °C) and organic solvent ( N , N -dimethylacetamide, DMAc), the PPTA/PPy OSN membranes still exhibited excellent permeation and separation performance. Furthermore, at room temperature, the immersion experiment of the fabricated PPTA/PPy OSN membranes in both ethanol and DMAc for one month also proved the stability of long-term organic solvents. Based on the above results, this work offered a novel PPTA based hollow fiber nanofiltration membrane, which was expected to be applied in thermal and organic dye wastewater treatment .
研究领域:
环境科学
·
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
·
2025
·
IF 8.9
Fengdong Teng,Na Li,Ying Yuan,Junrong Yu,Yan Wang,Zuming Hu
The complex preparation process and high shrinkage of poly(p-phenylene terephthalamide) (PPTA) aerogel limit its wider application. Herein, PPTA and heterocyclic aramid (HPPTA) prepolymer were secondary polymerized to obtain Block-PPTA (BPPTA) with both rigid and flexible segments in the molecular chain. The rigid and flexible segments in molecular chain under non-solvent enable the rapid transformation of BPPTA solutions into well-shaped BPPTA gels. The BPPTA aerogel exhibits the advantages of low shrinkage, high thermal insulation, and high mechanical strength. Then, a small amount of MXene and AgNWs were attached to the surface of BPPTA aerogels by layer-by-layer spraying method, which not only enhanced the flame retardancy capability of the aerogels, but also made organic aerogels possible to be applied in the fields of electromagnetic interference shielding and thermoelectric conversion. This work provides an ideal strategy for the efficient preparation of low shrinkage para aramid aerogels and expands the application areas of aerogels.
研究领域:
材料科学
·
化学工程
✓ 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）