POLYMER
·
2018
·
IF 3.483
Guodong Zhou,Weitao Wang,Mao Peng
Molecular composites using rigid-rod macromolecules as the reinforcement have attracted tremendous research interest. However, dispersion of rigid-rod macromolecules at molecular level in the matrix remains a great challenge. Herein, we report new epoxy (EP)-based molecular composites with sulfonated aromatic polyamides , poly( p -sulfophenylene terephthalamide) (sPPTA) and poly(benzidine-2,2′-disulfonic acid terephthamide) (PBDT), as the reinforcement, which disperse uniformly in epoxy. Covalent bonds formed by the reaction between the sulfonic acid groups of the polyamides and epoxy prevent reaction-induced phase separation during high temperature curing. The novel molecular composites exhibit extraordinarily high strength and toughness, with maximum tensile strength of sPPTA/EP and PBDT/EP (100.2 ± 4.8 MPa and 121.9 ± 12.5 MPa, respectively) increased by ∼81% and ∼120%, respectively. To the best of our knowledge, the improvement of mechanical properties surpasses those of molecular composites, nanofiller reinforced thermosets and liquid crystalline thermosets ever reported.
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
INDUSTRIAL CROPS AND PRODUCTS
·
2023
·
IF 5.9
Nan Li,Sufeng Zhang,Yali Liu,Valentin Nica,Sergiu Coseri
Cellulose-based materials are currently considered prime candidates for replacing petrochemical plastics because they are biodegradable and cost-effective, while the insufficient hydrophobicity makes them fail to meet application demands, which is a primary issue to be addressed. This work developed a green, catalyst-free approach to prepare high-hydrophobicity amidated cellulose (ADC) by anchoring the COOH-containing oleic acid (OLA) onto NH 2 -containing aminated cellulose (AMC) via amide bonds. The unsaturated fatty acid tail provides a hydrophobic barrier in ADC films . The surface water contact angle of the ADC film reached 133° and remained above 110° for at least one hour. Subsequently, the ADC suspension was applied on the surface of paper from old corrugated container (P-OCC) by an impregnation approach to investigate the improvement of hydrophobic properties. The results showed that the hydrophobicity of P-OCC was increased by ADC, with the water contact angle reached to 132° from 0°. Noticeably, the tensile strength of the ADC impregnated P-OCC (A-POCC) also increased by 2 times. This indicates that with excellent hydrophobicity and mechanical strength , the ADC has great potential application in green functional coating materials.
研究领域:
高分子材料科学
·
表面与界面化学
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生物质功能材料
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绿色化学
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包装材料工程
✓ 已验证
DOI
高影响因子
IRANIAN POLYMER JOURNAL
·
2019
·Vol. 28
·期 2
·157-166
·
IF 1.707
Zhang Guangyan,Zhou Jun,Wang Peng
A novel cross-linkable polyaspartamide derivative-containing cinnamoyl pendant groups, P(HPA-Az)-CA, was designed and synthesized in this study. Chemical structures of the obtained polymers were confirmed by FTIR, UV, and 1 H NMR techniques. The transmittance measurement results showed that the prepared polymer P(HPA-Az)-CA displayed temperature and pH dual stimuli-responsive behaviors. The cloud point of P(HPA-Az)-CA could be tuned just by adjusting the introduced percentage of hydrophobic moieties or the pH of polymer aqueous solution. The effect of pH on the cloud point of P(HPA-Az)-CA was investigated by zeta potential, and the results showed that it may be related to the weakened electrostatic repulsion caused by decreased zeta potential with pH decreasing. Diamines (ethylenediamine or cystamine) were adopted to prepare cross-linked micelles using the mixture of P(HPA-Az)-CA aqueous solution and diamines just by one-step heating method. The cross-linked micelles were stable, even when the environmental temperature was below the cloud point of P(HPA-Az)-CA. The cross-linking mechanism between the diamines and α,β-unsaturated carbonyl moieties of P(HPA-Az)-CA was confirmed by 1 H NMR. In addition, the micelles cross-linked with cystamine could be disrupted in the presence of 10 mM glutathione. According to the results, the obtained polyaspartamide derivative P(HPA-Az)-CA may be a potential for facilitating drug loading.
研究领域:
高分子化学
·
药物传递系统
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Qing Zhang,Zhenping Ma,Xin Jing,Hao-Yang Mi,Yuejun Liu,Songwei Li
The polyamide (PA) reverse osmosis (RO) membranes prepared by interfacial polymerization at a free aqueous–organic interface always suffer from polymerization instability on the free-interface and low chlorine resistance. Focusing on these problems, in this study, a new approach was proposed which introduced an additional buffer layer to assist the free-interfacial polymerization (BLFIP). And due to the adjustment of the mitigation of the organic phase and water phase on the free-interface, defect-free PA membranes with significantly improved surface smoothness were successfully prepared by the proposed BLFIP process and the resultant membranes demonstrated superior desalination performance compared to the PA membranes prepared with the previous technique. With the optimized concentration of 0.3 wt.% trimesoyl chloride (TMC) and 0.6 wt.%, m-xylylenediamine, the prepared BLFIP PA membrane showed salt rejection rate of 92.55%, 92.01%, 83.99% and 95.16%, to Na 2 SO 4 , MgSO 4 , NaCl and methyl orange, respectively at 5 bar, while maintained a water flux of about 2 Lm –2 h –1 bar –1 . More importantly, the BLFIP PA membrane possesses excellent long-term stability, and chlorine resistance comparing with traditional PA membranes based on TMC and m-phenylenediamine, which demonstrated the new method in this study paved a facile way for preparing RO filtration membranes with outstanding performance in seawater desalination.
研究领域:
材料科学
·
膜分离技术
·
环境工程
·
水处理
·
高分子化学
·
界面化学
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2017
·Vol. 25
·期 10
·1435-1441
·
IF 1.174
Zhirong Chen,Weitao Yang,Hong Yin,Shenfeng Yuan
The uncatalyzed reaction of p -tolyl isocyanate ( p -TI) with water in N , N -dimethylformamide (DMF) was investigated by high performance liquid chromatography (HPLC). The reactions were carried out at different temperatures from 293 K to 323 K, using various molar ratios of water to p -TI. DMF, as a special amide , was proved to be an efficient catalyst for water–isocyanate reaction. Under the reaction conditions in this study, substituted urea was the only final product observed. An appreciable amount of intermediate p -toluidine was detected. Concentrations of the isocyanate group as well as the amine and urea were determined as a function of time. New kinetic equations were deduced for each of the substance on the basis of a multistep mechanism, instead of a simple second order reaction as usual. Kinetic constants were calculated using the software MATLAB . Furthermore, the effects of temperature and concentrations of reactants on the reaction rate and amine content were discussed. The activation energy of each step was also determined.
研究领域:
物理化学
·
有机化学
·
反应动力学
·
高分子化学
·
催化化学
·
分析化学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2017
·
IF 6.216
Xiang Li,Huaili Zheng,Yili Wang,Yongjun Sun,Bincheng Xu,Chuanliang Zhao
Modified natural polymer flocculants has been the focus of research in environmental engineering field. Natural large molecular compound, chitosan (CTS) with many functional amino and hydroxyl groups can be easily modified to enhance its original functions. This work presents an environmentally friendly chitosan-based cationic polyacrylamide flocculants (CTS-g-PAMA) with enhanced function of sterilization and flocculation . CTS-g-PAMA was synthesized through Ultraviolet (UV)-initiated copolymerization. Structure characterization of FTIR, 1 H NMR, XRD and UV spectrum confirmed the successful grafting of AM and MAPTAC. Scanning electron microscopy (SEM) analysis results showed that CTS-g-PAMA exhibited a porous structure with a prodigious surface area. CTS-g-PAMA was then applied to treat a series of simulated waste water containing kaolin or Escherichia coli . Flocculation tests indicated that CTS-g-PAMA not only showed excellent flocculation effect but also showed high sterilization capability. A series of ONP concentration measurement tests through UV spectra analysis and 3D EEM analysis of suspension before and after flocculation were conducted to study sterilization mechanism, and results revealed the sterilization effect of CTS-g-PAMA was essentially bactericidal, not just antibacterial.
研究领域:
环境工程
·
高分子化学
·
水处理技术
·
材料科学
·
微生物学
✓ 已验证
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2018
·
IF 6.578
Shaosuo Bing,Jiaqian Wang,Hao Xu,Yanyan Zhao,Yong Zhou,Lin Zhang,Congjie Gao,Li’an Hou
Polyamide (PA) thin-film composite (TFC) reverse osmosis membrane is widely used for desalination , but the selectivity-permeability trade-off and oxidation are two major restrictions on the membrane application. By modifying PA TFC membrane with potassium persulfate (K 2 S 2 O 8 ), we overcame the trade-off relation (the water flux and salt rejection increased by 43.2% and 0.2%, respectively) and improved the chlorine resistance. The modification was demonstrated to be a combination of the interfacial crosslinking between PA layer and polysulfone support with the surficial oxidation of PA layer. The dense crosslinked interface enabled the membrane with higher solute rejection, better chlorine tolerance and long-term stability. Meanwhile, the thinner PA layer contributed to the increase of membrane permeability. Furthermore, the modification method has the application potential in high-performance membrane fabrication in terms of simplicity and high efficiency.
研究领域:
材料科学
·
膜分离技术
·
高分子化学
·
环境工程
·
水处理
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2017
·
IF 2.299
Xiu-Li Wang,Xiao-Mei Wu,Guo-Cheng Liu,Qiao-Min Li,Hong-Yan Lin,Xiang Wang
By tuning metal ions and combining with different dicarboxylates , four new semi-rigid thiophene-bis-pyridyl-bis-amide-based coordination polymers , namely, [Zn(3-bptpa)(1,3-BDC)]·DMA·2H 2 O ( 1 ), [Zn(3-bptpa)(5-MIP)] ( 2 ), [Cd(3-bptpa)(1,3-BDC)]·2H 2 O ( 3 ) and [Cd(3-bptpa)(5-MIP)]·4H 2 O ( 4 ) (3-bptpa= N,N′ -bis(pyridine-3-yl)thiophene-2,5-dicarboxamide, 1,3-H 2 BDC=1,3-benzenedicarboxylic acid, 5-H 2 MIP=5-methylisophthalic acid, DMA= N,N -dimethylacetamide), were solvothermally/hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction analyses, IR spectra , UV–vis diffuse-reflectance spectra (DRS), powder X-ray diffraction (PXRD) and thermal gravimetric analyses (TG). The structural analysis reveals that Zn-complexes 1 and 2 are similar 2D networks. While Cd-complexes 3 and 4 exhibit similar 2-fold interpenetrating 3D α -Po frameworks with the (4 12 ·6 3 ) topology. The photocatalytic properties for the degradation of methylene blue (MB) under ultraviolet light irradiation of the title complexes have been investigated in detail. Furthermore, the luminescent sensing behaviors for metal cations of 1–4 have been studied, the results indicate that 3 is an excellent fluorescent probe , with high sensitivity, selectivity , and simple regeneration, for environmentally relevant Fe 3+ ions.
研究领域:
无机化学
·
材料化学
·
配位化学
·
环境分析
·
光催化
·
荧光传感
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Murong Xi,Zhenjie Liu,Rui Sheng,Jiafeng Zhu,Yong Guo,Juan Ding,Xingchao Wang,Yue Zhang,Lei Wang,Zhipeng Sun,Wenjun Zhang,Jiulin Wang,Yudai Huang
Dissolutions of the polymer in the chaotropic salts follow Hofmeister effect, and the aggregate of salts and solvents shows new influence of the Hofmeister effect. Here, we reveal the aggregation of ion–solvent in chaotropic salt solution catalyzes the formation of the exposed Lewis acid-base center and realizes the dissolution of polyamide (PA) macromolecules. The relationship between Hofmeister effect, aggregate chemistry and Lewis acid-base chemistry is examined from new perspective. And then, a new solvent system and phase conversion process are designed for polyamides. Finally, the applications of PA in ZIBs as coating layer and binder are realized. As an electrode coating, it can effectively inhibit hydrogen evolution, corrosion and dendrite problems and improve the cycle life (cycle over 1500 h at 0.5 mA cm −2 ). As a binder, the active material adhesion on current collector, uniformity and wettability of the electrode are improved. The assembled pouch-cell with PANI cathode shows a capacity of 150 mAh g −1 after 120 cycles. This work reveals the secret of controlled phase transformation of polyamide in saline solution from a new perspective. And this phase conversion method is simpler, greener and more environmentally friendly, which greatly accelerates the application of polyamide in the field of membrane science and binder science.
研究领域:
高分子化学
·
电化学
·
材料科学
·
能源存储
·
膜科学
·
粘结剂科学
·
物理化学
✓ 已验证
DOI
高影响因子
CARBON
·
2018
·
IF 7.082
Yiwen Hu,Yongxin Wang,Zhixiang Zeng,Haichao Zhao,Xuewu Ge,Kai Wang,Liping Wang,Qunji Xue
Dispersion of Graphene in water is conducive to their practical applications as lubricating additive in water-based fluids due to their safety, low cost and environmental-friendliness. But owing to its hydrophobicity , it is difficult to achieve stable aqueous graphene suspension. Here, we use the Toluene-2,4-diisocyanate as bridging agent between hydrophilic Poly (ethylene glycol) (PEG) and ethanolamine to prepare the amino-containing PEG (PEG-NH 2 ), followed by covalently grafting PEG-NH 2 onto the surface of carboxylaed graphene (G-COOH) nanosheets to synthesize the PEGlated graphene (PEG-G) via facile amidation under mild conditions. The physical, chemical properties of product were characterized by Fourier transformed infrared spectra (FTIR), Raman spectra , X-ray photo electron spectroscopy (XPS) and so on. Transmission electron microscopy (TEM) and scanning probe microscope (SPM) were utilized to observed the morphology of G-COOH and PEG-G. The frictional properties of PEG-G as nanoadditive of water-based lubricant were characterized by UMT-3 tribometer, following with analyzes on wear surfaces by 3D laser scanning confocal microscopy . Based on the results of characterization, the PEG-G was prepared successfully and the dispersion shows superior friction-reducing and anti-wear properties owing to the formation of fluid adhesive film and carbon protective film, especially the concentration of PEG-G in water is 0.05 wt%.
研究领域:
材料科学
·
纳米科技
·
表面工程
·
摩擦学
·
高分子化学
·
应用化学
✓ 已验证
DOI
高影响因子
COLLOID AND POLYMER SCIENCE
·
2014
·Vol. 292
·期 10
·2633-2645
·
IF 2.41
Cong Houluo,Zheng Sixun
In this contribution, we reported the synthesis of poly( N -isopropylacrylamide)- block -poly(acrylic acid) (PNIPAAm- b -PAA) copolymer networks via sequential reversible addition-fragmentation chain transfer (RAFT) polymerization. The PNIPAAm- b -PAA block copolymer networks were characterized by means of Fourier transform infrared spectroscopy (FTIR) and small angle X-ray scattering (SAXS). The volume phase transition (VPT) temperatures of the PNIPAAm- b -PAA hydrogels were measured by means of micro-differential scanning calorimetry (micro-DSC). It was found that the block copolymer hydrogels displayed the VPT temperatures lower than the control PNIPAAm hydrogel. Compared to the control PNIPAAm hydrogel, the deswelling and reswelling properties of the block copolymer hydrogels were significantly improved. The improved thermoresponsive properties of the PNIPAAm- b -PAA hydrogels have been interpreted on the basis of the formation of the architecture of the block copolymer networks.
研究领域:
高分子化学
·
生物材料
·
药物递送
·
组织工程
·
智能响应材料
✓ 已验证
DOI
高影响因子
RSC Advances
·
2018
·Vol. 8
·期 66
·38003-38012
·
IF 2.936
Xiuqiong Chen,Huiqiong Yan,Wei Sun,Guangying Chen,Changjiang Yu,Wen Feng,Qiang Lin
To achieve the dispersion of the hydrophobic graphene (GR), the amphiphilic alginate caprylamide (ACA) was synthesized to fabricate electroactive Nafion/Mb–ACA–GR/CILE for the accurate determination of trichloroacetic acid (TCA). SEM observation, FT-IR and UV-Vis spectroscopic analysis indicated that ACA could tightly immobilize Mb and GR on the electrode surface by constructing biointerfaces, which not only provided Mb a suitable microenvironment to maintain its biological activity, but also shortened the distances between the active centers of Mb with carbon ionic liquid electrode (CILE), thus promoting the electron transfer rate. The electrochemical characterization of Nafion/Mb–ACA–GR/CILE showed that the direct electron transfer of Mb was realized on the modified electrode, which was attributed to the high electrical conductivity and excellent electrocatalytic activity of GR and good biocompatibility of ACA. Moreover, Nafion/Mb–ACA–GR/CILE exhibited good electrocatalytic activity towards TCA with the linear range from 2.5 to 47.3 mmol L−1 and lower KMapp value of 8.3 mmol L−1. Moreover, the modified electrode also revealed good stability, reproducibility and accurate detection of tap-water, exhibiting great potential for the applications as the third-generation electrochemical biosensors.
研究领域:
生物医学工程
·
电化学传感
·
纳米生物技术
·
分子生物学
·
分析化学
·
生物传感器
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）