HIGH PERFORMANCE POLYMERS
·
2013
·
IF 0.85
Chaoyun Luo,Jiandong Zuo,Jianqing Zhao
An epoxy prepolymer with high refractive index, diglycidyl ether of thiodiphenol (DGETP), was synthesized by 4,4′-thiodiphenol and epichlorohydrin via a two-step method. The curing agent o-benzenedimethanethiol (OBDMT) was synthesized by thiourea method. Fourier transform infrared spectroscopy and proton nuclear magnetic resonance were employed to characterize the structures of these resins. The cured product of DGETP and OBDMT was analyzed by differential scanning calorimetry, ultraviolet–visible spectrometer, and Abbe refractometer and compared with the property of traditional curing agent of methyl hexahydrophthalic anhydride (MHHPA) and ordinary bisphenol A diglycidyl ether epoxy prepolymer cured products. The lower curing temperature and glass transition temperature of DGETP than those of MHHPA can be mainly attributed to the strong rotation capability of thioether bond. The zero light transmittance region of DGETP/OBDMT curing adhesive (200–380 nm) was broader than that of the other three. The refractive index of DGETP/OBDMT was up to 1.654.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2013
·Vol. 31
·期 10
·1359-1371
·
IF 1.27
Zhang Tao,Yan Hong-qiang,Fang Zheng-ping,Peng Mao
Three kinds of novel aromatic diamine-based benzoxazines containing naphthalene, propane-2,2-diyldibenzene and neopentyl groups in the backbone, respectively (designated as BAPNCP, BAPBACP and BAPNPGCP, respectively), were synthesized and characterized. In addition, the effects of backbone structures on curing behaviors of the monomers and thermal and flammability properties of the resulting polymers were systematically studied. The results indicated that BAPNPGCP displayed the highest enthalpy of the curing reaction associated with the ring-opening of benzoxazine, which was due to the effect of benzoxazine ring content per unit mass. Interestingly, the 5 wt% weight loss temperature and char residue after thermogravimetric test for poly(BAPNPGCP) were 8 °C and 7% higher than those of poly(BAPBACP). Meanwhile, the total heat release of poly(BAPNPGCP) was less than half of that for poly(BAPBACP), indicating the substantial effect of benzoxazine ring content on flammability and char formation. Furthermore, it was found that poly(BAPNCP) gave the best thermal stability and flame retardancy, which was due to the synergistic effect between naphthalene group and benzoxazine ring content. This study provides new insight into the curing behavior of benzoxazine and further understanding on the high performance of polybenzoxazine.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
·
2012
·
IF 1.634
Fu Liu,Zhongbo Wei,Liansheng Wang,Zunyao Wang
4,4′-Dihydroxydiphenyl ether and 4,4′-oxybis(1-methoxybenzene) are synthesized. Experimental and theoretical studies on molecular structure, infrared spectra (IR), Raman spectra and nuclear magnetic resonance ( 1 H NMR) chemical shifts of the two synthesized compounds have been worked out. All the theoretical results, which are obtained with B3LYP/6-311G(d,p) method by using the Gaussian 09 program, have been applied to simulate molecular structure, infrared, Raman and NMR spectra of the compounds. The compared results reveal that the calculated geometric parameters match well with experimental values; the scaled theoretical vibrational frequencies are in good accordance with observed spectra; and computational chemical shifts are consistent with the experimental values in most part, except for some minor deviations. These great coincidences prove that the computational method B3LYP/6-311G(d,p) can be used to predict the properties of other similar materials where it is difficult to arrive at experimental results.
研究领域:
化学
·
理论计算化学
·
光谱学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 29
·e52647
·
IF 3.057
Jinrong Yin,Yunlei Gong,Huaan Zheng,Hui Yuan,Zhen Zeng,Wei Qin,Chenghao Li,Yang Zhou,Xianyan Ren
Ultra-low-density proppants are of great significant in slick water fracturing system, but the polymer composite microspheres can hardly promise the quality of oil and gas due to their poor hydrophobicity. To address the issue, we prepared several types of modified styrene-divinyl benzene copolymer microspheres (MSDBs) with long-term durable hydrophobicity and high strength, including O-MSDBs (hydrophobic MSDBs), LO-MSDBs (long-time hydrophobic MSDBs), and CO-MSDBs (coated O-MSDBs) on the basis of a molecular structure of “KH570-styrene (St)-divinyl benzene (DVB)” copolymer. In this article, the design concept and the structure of MSDBs was clarified, and performances of MSDBs are systematically discussed and compared with commercially available hydrophobic microspheres. The O-MSDBs, a kind of nanoparticle patterned St-DVB copolymer microspheres, were prepared by a one-step suspension polymerization undergoing a sol–gel process, showing strong hydrophobicity with a water contact angle up to 140.7°, but short durability in strong hydrochloric acid or hydrofluoric acid; On the contrary, LO-MSDBs perform better in the stability and durability of hydrophobicity with a slightly lower water contact angle about 135.9°. The LO-MSDBs were designed by coating functionalized St-DVB copolymer microspheres with fluororesin. Similarly, CO-MSDBs from fluororesin-coated O-MSDBs were designed. As expected, CO-MSDBs have a stronger hydrophobicity (139.0°) than LO-MSDBs and longer durability than O-MSDBs. Moreover, the MSDBs exhibit better properties than the commercially available hydrophobic polymer and ceramic microspheres.
研究领域:
材料科学
·
石油工程
✓ 已验证
DOI
高影响因子
ADVANCES IN POLYMER TECHNOLOGY
·
2021
·
IF 2.389
Yuanying Zhang,Xuechun Zhang,Yongbin Cao,Jiachun Feng,Wuli Yang
Herein, acrylonitrile-styrene-acrylate copolymer (ASA) particles with different microstructure were synthesized by emulsion polymerization and then used for toughening poly(styrene-co-acrylonitrile) (SAN) resin. The structure of ASA particles was confirmed by FTIR. TEM results demonstrated that the particles with different morphologies of multilobe shape, complete core-shell and dumbbell shape were obtained depending on the cross-linker amount. It was found that the toughening efficiency reached the highest when the ASA particles had complete core-shell structure and the shell composition was close to that of the SAN matrix. It was ascribed to the fact that the complete shell layer and similar shell composition provided sufficient interfacial adhesion and transferred stress to induce larger matrix deformation, so that the notched impact strength increased accordingly. Moreover, the notched impact strength of SAN/ASA blend was improved without significantly sacrificing tensile strength when adding 30 wt% ASA particles with the size of around 400 nm. SEM results of the impact-fractured surfaces revealed that irregular fluctuation and numerous microvoids occurred. It was deduced that the toughening mechanism was attributed to the crazings and cavitation of particles. Therefore, this study paved a way of toughening the resin by adjusting the microstructure of the particles including morphology, composition, and size.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
AQUATIC TOXICOLOGY
·
2024
·
IF 4.1
Yonghua Wang,Yujia Shang,Xiaodan Liu,Xi Chen,Guanhua Xu,Guanghua Lu
Benzophenone-3 (BP-3) is a commonly used ultraviolet absorber that has the potential to accumulate in organisms, leading to toxicity. Benzophenone-8 (BP-8) is one of the major metabolites of BP-3. In this study, zebrafish were exposed to different concentrations of BP-3 and BP-8 (1 μg/L, 30 μg/L, and 300 μg/L) to investigate their accumulation and toxic effects in various tissues, including zebrafish brain, gut, and liver. The analysis focused on neurotoxicity, oxidative damage, inflammation, and gene expressions. The results showed that both BP-3 and BP-8 accumulated in the tissues, with the highest concentration observed in the gut, followed by the liver and brain. BP-8 exhibited a stronger ability to accumulate. In the brain, exposure to 1 μg/L of BP-3 and BP-8 promoted cortisol production, while higher exposures (30 μg/L and 300 μg/L) inhibited acetylcholinesterase activity and suppressed cortisol production. In the gut, both BP-3 and BP-8 exposures disrupted oxidative stress, inflammatory immunity, and apoptosis functions. In the liver, BP-3 and BP-8 affected hepatic metabolism, oxidative stress, apoptosis, and inflammatory immunity. Comparing gene expression in the brain, gut, and liver, it was found that BP-3 and BP-8 had a lower effect on gene expression in the brain, while the effect on the gut and liver was significantly higher. BP-8 generally had a higher effect than BP-3, which aligns with the observed accumulation pattern. These findings provide valuable insights for the risk assessment of BP-3 and BP-8 in the aquatic environment.
研究领域:
环境毒理学
·
水生毒理学
·
分子生物学
·
生物化学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 64
·33702-33712
·
IF 3.708
Yepei Zhang,Baohua Yue,Shuaiyuan Han,Liuming Yan
The synergetic proton conducting effect with three orders of magnitude improvement in proton conductivity was observed in an acid–base composite composed of phosphonic acid functionalized polystyrene (PS-PA) and triazolyl functionalized polystyrene (PS-Tri). In addition, a new method for the development of proton conducting materials by the combination of different acidic and basic polymers is proposed. The PS-PA was synthesized by the bromination of polystyrene on the para-position of the phenyl ring followed by phosphonation and hydrolysis. The PS-Tri was synthesized by the chloromethylation of polystyrene on the para-position of the phenyl ring followed by azidation and 1,3-dipolar cycloaddition or ‘click’ reaction. A maximum proton conductivity of 11.2 mS cm−1, which is three orders of magnitude higher than that of pristine PS-PA or PS-Tri, a tensile strength of 16.3 MPa, and a minimum water uptake of 15.1% (90 °C, 90% RH) were observed in the PS-PA/PS-Tri composite composed of 66.7% PS-PA. Finally, a mosaic-like morphology model and space-charge effects were proposed to explain the synergetic proton conducting effect.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
ENVIRONMENT INTERNATIONAL
·
2020
·
IF 7.577
Fangjing Lin,Jianteng Sun,Na Liu,Lizhong Zhu
Polychlorinated biphenyls (PCBs) and their biotransformation products, hydroxylated (OH-PCBs) and methoxylated derivatives (MeO-PCBs), have been detected in the environment and biota, especially crops. However, to date, little information is available on the phytotoxicity and metabolic responses induced by these chemicals in crops. In this study, we exposed rice ( Oryza sative L.) seedlings to 2,3,4,5-tetrachlorobiphenyl (CB-61) and its hydroxylated (4′-OH-CB-61) and methoxylated derivatives (4′-MeO-CB-61) at 0, 10, 50, 100 and 500 μg/L, respectively. After exposure for 14 days, significantly growth inhibition and oxidative damage were observed, among which the toxicities of 4′-OH-CB-61 and 4′-MeO-CB-61 were greater than that of the parent PCBs. Metabolomics analysis indicated that exposure to the three chemicals induced different metabolic responses. 4′-MeO-CB-61 mainly affected the saccharide catabolism, including pyruvate metabolism, the TCA cycle, the transfer of acetyl groups into mitochondria and the Warburg effect, resulting in a greater energy consumption. Moreover, both CB-61 and 4′-OH-CB-61 promoted several amino acid metabolism and fatty acid biosynthesis, thereby alleviating the potential ROS damage. This study for the first time evaluates and reveals the phytotoxicity of OH-PCBs and MeO-PCBs at the metabolic level, which attempts to provide important information for accurately evaluating the environmental risks of PCBs from the perspective of metabolism.
研究领域:
环境科学
·
植物生物学
·
毒理学
·
代谢组学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
·
2019
·Vol. 166
·期 14
·B1293
·
IF 3.12
Yu Zhang,Qiang Xie,Zhi Xia,Guofeng Gui,Feng Deng
In this paper, a novel nanocomposite fulvic acid reduced graphene oxide (FA-rGO) and Co-phthalocyanine nanorods (CoPcNRs) was prepared and used to construct an electrochemical sensor for simultaneous detection of catechol (CC), hydroquinone (HQ), phenol (PN) and p-nitrophenol (p-NP). FA as reductant used to prepare FA-rGO nanocomposite, which fabricated by hydrothermal method and freeze-drying process. The method is environmentally friendly and realizes the gentle reduction of GO. CoPcNRs were synthesized by surfactant-assisted ultrasonic method. The microstructure and morphologies of the as-prepared materials were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and UV-Vis spectrophotometer. The electrochemical oxidation of CC, HQ, PN and p-NP was investigated using differential pulse voltammetry (DPV). The results show that the FA-rGO/CoPcNRs modified electrode exhibits excellent electrochemical activity toward the simultaneous redox of CC, HQ, PN and p-NP. Under optimal conditions, the linear ranges of CC, HQ, PN and p-NP were 1 μM–650 μM, 2 μM–450 μM, 2 μM–160 μM, 2 μM–140 μM, with 0.3 μM, 0.65 μM, 0.65 μM and 0.65 μM, respectively. In addition, the modified electrode showed good selectivity, sensitivity and stability. The application in real samples was also evaluated, and the recoveries suggesting that FA-rGO/CoPcNRs nanocomposites could be used as an excellent potential reaction platform for the simultaneous determination of CC, HQ, PN and p-NP in environmental samples.
研究领域:
环境科学
·
材料科学
·
分析化学
✓ 已验证
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL PHYSICS
·
2020
·Vol. 33
·期 6
·749-756
·
IF 1.067
Zhou Xue-zheng,Yan Xiang-yang,Zhu Ling,Ma Ming,Dai Ya,Wang Chang-guo,Zhu Li-jun,Yu Ke-jie,Liu Shao-min
A new kind of phenyl-functionalized magnetic fibrous mesoporous silica (Fe 3 O 4 @SiO 2 @KCC-1-phenyl) was prepared by copolymerization as an efficient adsorbent for the magnetic extraction of phthalate esters from environmental water samples. The obtained Fe 3 O 4 @SiO 2 @KCC-1-phenyl showed monodisperse fibrous spherical morphology, fairly strong magnetic response (29 emu/g), and an abundant π -electron system, which allowed rapid isolation of the Fe 3 O 4 @SiO 2 @KCC-1-phenyl from solutions upon applying an appropriate magnetic field. Several variables that affect the extraction efficiency of the analytes, including the type of the elution solvent, amount of adsorbent, extraction time and reusability, were investigated and optimized. Under optimum conditions, the Fe 3 O 4 @SiO 2 @KCC-1-phenyl was used for the extraction of four phthalate esters from environmental water samples followed by high-performance liquid chromatographic analysis. Validation experiments indicated that the developed method presented good linearity (0.1–20 ng/mL), low limit of detection (7.5–29 µg/L, S / N =3). The proposed method was applied to the determination of phthalate esters in different real water samples, with relative recoveries of 93%−103.4% and relative standard deviation of 0.8%–8.3%.
研究领域:
环境科学
·
分析化学
✓ 已验证
DOI
高影响因子
Polymer Chemistry
·
2020
·Vol. 11
·期 35
·5693-5700
·
IF 5.342
Taijun He,Zhenyu Xing,Yixing Wang,Difeng Wu,Yang Liu,Xiangyang Liu
Generally, surface initiated-atom transfer radical polymerization (SI-ATRP) often suffers from the immobilization of the initiator on the surface-inert substrate. Developing an effective and versatile one-step method to anchor the priming sites while retaining the bulk properties of the substrate still faces challenges. In this work, direct fluorination is proposed to treat the benzene ring-containing substrate and the C–F introduced on the benzene ring can be used as an initiation site to achieve SI-ATRP. Computer and molecular simulation experiments have shown that the C–F added on the phenyl ring is more suitable for initiating ATRP than the C–F on the alkane chain. Thereafter, polyethylene terephthalate (PET) fabric was successfully grafted with fluorinated methacrylate polymer via direct fluorination-initiated ATRP, resulting in durable superhydrophobic properties, which demonstrated the practicability of the method. Furthermore, fluorination-initiated ATRP presents universality with other phenyl ring-containing polymeric substrates, such as aramid fiber, polyimide fiber and poly-p-phenylene benzobisoxazole fiber. Among them, the fluorinated aramid fiber can be grafted with hydroxyethyl methacrylate to obtain increased interfacial shear strength.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
LIQUID CRYSTALS
·
2019
·
IF 3.078
Qiang Weng,Longyan Duan,Pei Chen,Aiai Gao,Xinbing Chen,Zhongwei An
Modifying the position and numbers of lateral fluorine substituent is a common method to design and adjust the mesophase of liquid crystal compounds. Here, a series of 2-(2,2ʹ-difluoro-4ʹ-alkoxy-1,1ʹ-biphenyl-4-yl)-5-substituted benzoxazole with both non-polar (H, CH3) and polar (NO2) groups (coded as nPF(2)PF(2)Bx) is synthesised and characterised. All of the compounds show a conspicuous inter-ring twist angle of 38° compared with corresponding reference compounds I and II which are calculated by density functional theory method, and it is interesting to note that the final compounds nPF(2)PF(2)Bx show only nematic mesophase during heating or cooling. Meanwhile, the UV-vis absorption bands and photoluminescence emission peaks both display remarkable blue-shifted. The aforementioned results reveal that lateral difluoro substituents play a key role to stable the nematic mesophase by increasing the dihedral angle of biphenyl.
研究领域:
材料科学
·
化学
·
液晶
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）