JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 22
·52263
·
IF 3.057
Jie Zhang,Zongwei Guo,Jinpeng Ma,Lingxiao Song,Guorui Yang,Yuhui Ao,Lei Shang,Ming Li
As an important thermosetting resin, epoxy resin (EP) is widely used in the field of composite materials. Long storage time, rapid curing and low viscosity of one-component EP is ideal for preparing composite materials by vacuum assisted resin transfer molding (VARTM). For this sake, we developed and synthesized a new imidazole thermal latent curing agent, 4,7-diimidazol-2,1,3-benzothiadiazole (BTD-MZ 2 ) with a yield of about 75%. The curing behavior, thermal stability and storage time of the prepared EP system was studied by differential scanning calorimeter (DSC), thermal gravimetric analyzer (TGA), modular compact rheometer (MCR), respectively. DSC results showed that EP/17.5 wt% BTD-MZ 2 had a good latent period at low temperature, and can rapidly cure EP when heated to 150°C. TGA results show that BTD-MZ 2 promoted the formation of carbon residue and the residual carbon rate of EP/17.5 wt% BTD-MZ 2 is as high as 37.9%. MCR results show that the storage time of EP/17.5 wt% BTD-MZ 2 at 60°C can reach 850 min. In addition, it could play a role of catalyst used as co-curing agents with aromatic amines for EP. DSC test showed that the addition of 5 wt% BTD-MZ 2 reduced the activation energy of EP/4,4′-diaminodiphenylmethane (DDM) and promoted the curing reaction.
研究领域:
材料科学
·
化学工程
·
高分子科学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2023
·
IF 5.9
Zheng Li,Zuodong Qin,Chunxuan Li,Guimei Zhang,Aozheng Zhang,Sisi Li,Guoqi Liang,Xin Wang,Wufei Tang
Nano calcium carbonate (CaCO 3 ) was successfully treated by tetrabutyl titanate sol together with nickel hydroxide, followed by calcination to form a new kind of flame retardant (Ni-TiO 2 @CaCO 3 ). After study of the Ni-TiO 2 @CaCO 3 structure, it was then introduced into epoxy resin (EP) to improve the flame retardancy and thermal stability. The results shown that NiO and TiO 2 were supported on the surface of the CaCO 3 , and 5 wt% CaCO 3 could enhance the flame retardancy and Ni-TiO 2 @CaCO 3 further increased the flame retardancy of the EP composites. In the cone calorimeter test (CCT), the values of the peak heat release rate (pHRR) and smoke production rate (pSPR) were reduced to 769 kW/m 2 and 0.32 m 2 /s by CaCO 3 from 1101 kW/m 2 and 0.39 m 2 /s of the raw EP respectively. Moreover, pHRR and pSPR values were further decreased to 511 kW/m 2 and 0.25 m 2 /s by Ni-TiO 2 @CaCO 3 respectively. Although the degradation temperature values were lower than that of the control EP, the temperature values at 5 and 50% mass loss for Ni-TiO 2 @CaCO 3 /EP composites were improved compared to the EP. In addition, the char residues value of the Ni-TiO 2 @CaCO 3 / EP composite (23.5%) was obviously improved compared to that of the EP (13.0%) and CaCO 3 / EP composite (16.4%). In addition, the flame retardancy mechanism of the Ni-TiO 2 @CaCO 3 / EP composite was thoroughly analyzed by TGA-FTIR, FITR and Raman methods. This work provides a promising evaluation strategy for utilizing CaCO 3 and its derivatives for possible treatment of EP to enhance its flame retardancy and thermal stability.
研究领域:
材料科学
·
高分子科学
·
消防安全工程
✓ 已验证
产品关联
DOI
高影响因子
MOLECULAR PLANT PATHOLOGY
·
2021
·Vol. 22
·期 7
·817-828
·
IF 5.663
Xianping Fang,Weiguo Chai,Shuigen Li,Liqing Zhang,Hong Yu,Jiansheng Shen,Wenfei Xiao,Aichun Liu,Boqiang Zhou,Xueying Zhang
In this study, we used virus-mediated gene silencing technology and found that the HSP17.4 gene-silenced cultivar Sweet Charlie plants were more susceptible to Colletotrichum gloeosporioides than the wild-type Sweet Charlie, and the level of infection was even higher than that of the susceptible cultivar Benihopp. The results of differential quantitative proteomics showed that after infection with the pathogen, the expression of the downstream response genes NPR1 , TGA , and PR-1 of the salicylic acid (SA) signalling pathway was fully up-regulated in the wild-type Sweet Charlie, and the expression of the core transcription factor MYC2 of the jasmonic acid (JA) pathway was significantly down-regulated. The expression of the proteins encoded by these genes did not change significantly in the HSP17.4 -silenced Sweet Charlie, indicating that the expression of HSP17.4 activated the up-regulation of downstream signals of SA and inhibited the JA signal pathway. The experiments that used SA, methyl jasmonate, and their inhibitors to treat plants provide additional evidence that the antagonism between SA and JA regulates the resistance of strawberry plants to C . gloeosporioides .
研究领域:
植物病理学
·
分子生物学
·
植物遗传学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Ling Liu,Yanbo Li,Man Xu,Cunwen Wang
Two-dimensional Co ultrathin metal–organic framework nanosheets (Co-UMOFNs) were synthesized and blended into poly (ether block amide) (PEBA) to prepare composite mixed matrix membranes on PVDF supports for the pervaporation of phenol aqueous solution. The membranes were characterized by XRD, ATR-IR, TGA, CA and SEM measurements. Effects of the Co-UMOFNs loading, feed temperature and feed concentration on phenol separation performance were investigated. The results showed that Co-UMOFNs have a two-dimensional layered morphology and have good compatibility with the PEBA. A “brick and mortar” architecture morphology was achieved after incorporating Co-UMOFNs into the PEBA membrane. The amorphous PE segments in the PEBA were turned into a crystalline structure, restricting the motion of PE segments. The filling of Co-UMOFNs slightly improved the thermal stability and hydrophobicity as well. With the increase of the Co-UMOFNs loading from 0% to 40%, the phenol separation factor increased from 27 to 45, and the total flux decreased from 1.2 kg m -2 h - 1 to 0.42 kg m -2 h - 1 , when separation of 1000 ppm phenol solution at 70 °C. The interlayer galleries induced by the Co-UMOFNs stacking increased the tortuosity, and the crystalline structure of the Co-UMOFNs-PEBA improved the energy barriers of water penetration. Therefore the water flux was inhibited and the phenol separation factor increased. Depression of water permeation can be another protocol to prepare high-performance organophilic pervaporation membranes.
研究领域:
材料科学
·
化学工程
·
膜技术
✓ 已验证
DOI
高影响因子
JOURNAL OF SOLID STATE CHEMISTRY
·
2021
·
IF 3.498
Biao Wu,Meng Yan,Fen Luo,Xiaoyan Shu,Yi Liu,Guilin Wei,Zhentao Zhang,Yi Xie,Xirui Lu
Spent nuclear fuel contains 129 I, which has deleterious effects on human health. This study focused on the immobilization of iodine waste forms via a novel preparation method with B 2 O 3 –Bi 2 O 3 –ZnO–SiO 2 glass at 500–600 °C. The XRD results manifest that the sample with 30 wt % iodine sintered at 550 °C exhibits an obvious amorphous phase. The density of the samples with different iodine contents increases with the temperature increasing, so does the amorphous fraction except for 25 wt %. The FT-IR results reveal the matrix is mainly composed of [BO 3 ], [BO 4 ], [SiO 4 ], and [BiO 6 ]. TGA analysis shows high water content in the prepared samples. SEM-EDS results present that at 550 °C one part of the iodine is chemically immobilized into the glass matrix, and meanwhile, the other physically packed by the vitrified bulk. Our findings demonstrate the potential of the new preparation method for the disposal of iodine waste forms.
研究领域:
核废料管理
·
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
CORROSION SCIENCE
·
2019
·
IF 6.355
Yunxing Pan,Shengli Cheng,Hang Dong,Nan Li,Feng Bao,Jinyan Wang,Xigao Jian
A novel oxidation resistant thermoset polymer (MSCB) with excellent thermo-oxidative stability and good solubility was designed and synthesized. To prevent C/C composites from oxidation, a series of MSCB polymer-based coatings were prepared by precursor infiltration and thermal-curing at 300 ℃. The oxidation behaviour of the MSCB-, MSCB/TiO 2 -, MSCB/ZrO 2 - and MSCB/SiC-coated C/C composites was studied. The improved oxidation resistance of the C/C composites was attributed to the good adhesion of the coatings and the formation of a borosilicate protective layer on the surface of the coatings, which was confirmed by the results of TGA, SEM, XPS, and XRD analyses.
研究领域:
材料科学
·
聚合物化学
·
复合材料
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Inorganic and Organometallic Polymers and Materials
·
2019
·Vol. 29
·期 6
·2083-2089
·
IF 1.637
Song Peng,Tu Yu,Shen Xiaoping,Yuan Aihua,Zhai Linzhi,Shah Sayyar Ali
Silk fibroin (SF) derived composites play an important role in regenerative medicine and tissue engineering fields. In this study, through a simple, yet green and sustainable approach, ZIF-8@SF composite was firstly prepared, and its morphological, structural, thermal and mechanical properties were systematically studied. After ZIF-8 feeding, no marked side effect for silkworms was found. The as-prepared composite had 3% of ZIF-8, and a maximum strain of 28%, which was 17% higher than that of the natural SF. Results from SEM, FTIR, XRD and TGA showed that the essential characteristics of SF were well inherited with ZIF-8 addition, suggesting that ZIF-8@SF had a great potential of being used in bio-relevant fields. Noticeably, this study is the first time to develop ZIF-8@SF composite, and the in vivo feeding approach is very promising for commercial production.
研究领域:
材料科学
·
再生医学
·
组织工程
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2022
·
IF 6.364
Cunku Wang,Jie Ding,Zhixiong Huang,Yingluo Zhuang,Yan Li,Minxian Shi,Yan Qin
In this work, two ceramizable phenolic adhesives were prepared using ZrSi 2 particles or ZrSi 2 /B 4 C mix particles as the inorganic fillers. The thermal stability, bonding strength , microstructure and phase composition of the adhesives were investigated by TGA , shear strength of Al 2 O 3 joints, SEM, EDS , XRD and XPS . The results show that these two adhesives have different bonding performances and ceramicization evolutions above 600 °C in air due to the addition of the second phase particles B 4 C. The bonding strength of ZrSi 2 /B 4 C modified phenolic adhesive after treatment at 1200 ℃ can be as high as 36.6 MPa, while the bonding strength of ZrSi 2 modified phenolic adhesive under the same conditions is only 17.5 MPa. B 4 C undergoes oxidation reaction before ZrSi 2 , and the oxidation product B 2 O 3 liquid phase not only reacts with ZrSi 2 to form oxidation-resistant ZrB 2 , but also can dissolve the high temperatures defects of the adhesive and chemically bond with the Al 2 O 3 substrates at the interface.
研究领域:
材料科学
·
胶粘技术
·
热工程
·
表面科学
✓ 已验证
产品关联
DOI
高影响因子
Plasma Processes and Polymers
·
2024
·
IF 2.9
Rongzhao Jia,Shenli Jia,Jiajian Zhang,Yongpeng Mo,Zongqian Shi
A method for in situ fabrication of Al@C nanocomposite energetic additives through pulsed discharge in liquid cyclohexane has been proposed. The obtained Al@C nanocomposites consist of large aluminum nanoparticles (over 100 nm) enveloped by fullerenes and a carbon matrix with smaller aluminum particles (under 100 nm) embedded within. DSC–TGA curves indicate that the heat release of Al@C is higher than that of micron-sized and nano-sized aluminum particles. Al@C nanocomposites effectively reduce the ignition delay for liquid fuels. The energy efficiency of this method is much higher than that of continuous arc ablation, with a yield of up to 2.5 mg/min. This method allows for the simple, convenient, and safe fabrication of energetic additives, presenting a promising prospect for large-scale industrial production.
研究领域:
材料科学
·
化学工程
·
高能材料
·
纳米技术
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2021
·
IF 6.953
Fengjiao Cui,Huidong Li,Chen Chen,Zhixia Wang,Xinxin Liu,Gang Jiang,Tianjia Cheng,Runying Bai,Lei Song
In this study, cattail was researched as a natural cellulose source to extract cellulose. Dewaxing, alkali and bleaching treatments were carried out for the cattail fibers (CFs). The FTIR, SEM and XRD results indicated that hemicellulose and lignin were successfully removed from the CFs, and the content of cattail cellulose increased from 41.66 ± 1.11% to 89.72 ± 1.07%. Subsequently, cellulose aerogel was prepared by the extracted cattail cellulose. The Zeolitic imidazolate framework-8 (ZIF-8) was uniformly loaded onto the surface of cellulose aerogel by the in situ growth, and ZIF-8 Cattail Cellulose Aerogel (ZCCA) was finally prepared. The SEM, FTIR, XRD and TGA results further confirmed the successful preparation of ZCCA. Additionally, the results of the adsorption experiment showed that ZCCA had excellent adsorption performance for enrofloxacin, and the maximum adsorption capacity of enrofloxacin reached 172.09 mg·g −1 while showing good reusability. The adsorption process followed the pseudo-second-order kinetic model and the Langmuir isotherm model. Thermodynamic studies showed that the adsorption of enrofloxacin was a spontaneous endothermic reaction and that the adsorption mechanism involves the interaction of hydrogen bonds , electrostatic and π-π stacking.
研究领域:
环境科学
·
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
·
2021
·
IF 9.381
Yuyang Wu,Xincheng Jiang,Jiangya Ma,Jingbo Wen,Shuang Liu,Hongxia Liu,Huaili Zheng
A kind of starch-based flocculant (starch- graft -poly[(2-methacryloyloxyethyl) trimethyl ammonium chloride], denoted St-g-PDMC-LPUV) has been synthesized by low-pressure ultraviolet initiation and was employed to remove humic acid (HA) for water purification . The physicochemical characteristics of starch and St-g-PDMC-LPUV were characterized by FT-IR, 1 H NMR, XRD, TGA , SEM and BET to confirmed the successful grafting DMC onto starch. Effects of flocculant dosage, pH, the adding amount of Fe 3 O 4 , initial HA concentration and stirring speed were investigated systematically. The prepared St-g-PDMC-LPUV flocculant with non-toxic, biodegradability and environmental friendliness exhibited effective performance for removing HA from water in a wide pH range (5–10). The flocculation mechanism was attributed to the effective collision between function groups of the St-g-PDMC-LPUV flocculant and HA by charge neutralization, adsorption, bridging and patching.
研究领域:
环境科学
·
化学工程
·
材料科学
·
水处理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials Today Communications
·
2023
·
IF 3.8
Yuchun Ji,Zhengde Li,Laiping Zhang,Jilin Wang,Wenbiao Li,Wenzhuo Chen,Guoyuan Zheng,Fei Long,Zhengguang Zou
In this paper, a novel boron nitride hollow microtube (BNHM) structure by annealing assisted high-pressure etching method. The products were characterized by XRD , FTIR, Raman, XPS , SEM, TEM, TGA , BET, UV–vis, and PL. The result shows that the sample displayed a one-dimensional hollow tube structure directionally covered with nanosheets . The average inner diameter of the hollow tube is 1 µm with a length of 2–4.5 µm. And the wall thickness of the hollow tube structure is about 100 nm. In addition, the band gap value of the sample is 5.51 eV presenting the strongest absorption peak at 225 nm. The specific surface area of the sample is 272.6 m 2 ·g −1 , showing good adsorption efficiency on Congo red (absorbed 75% in 5 min). Meanwhile, the possible growth mechanism of BNHM is also discussed.
研究领域:
材料科学
·
纳米技术
·
化学
·
表面科学
✓ 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）