CRYSTENGCOMM
·
2020
·Vol. 22
·期 37
·6182-6188
·
IF 3.117
Xueshuai Chen,Rongli Jiang,Huilin Hou,Zihan Zhou,Xingwen Wang
ZSM-5/SAPO-34 zeolite composites were successfully synthesized by adding ZSM-5 into SAPO-34 synthetic gel under hydrothermal synthesis conditions, and SAPO-34 as a part of the composite zeolite was synthesized from LAPONITE® as the Si source. The presence of ZSM-5 in the synthetic gel affects the nucleation and crystal growth rate, and core–shell structured zeolite composites can be formed by adding an appropriate amount of ZSM-5. LAPONITE® itself contains Li and Mg atoms which were subsequently introduced into the framework of the SAPO-34 part in the composites via depolymerization–reorganization during the process of crystallization. Furthermore, the depolymerized LAPONITE® can be converted in situ into zeolitic precursors and act as crystalline seeds under hydrothermal conditions. Compared with the ZSM-5/SAPO-34 zeolite composites synthesized from tetraethylorthosilicate (TEOS) instead of LAPONITE® as the Si source, the ZSM-5/SAPO-34 composites synthesized from LAPONITE® exhibited higher selectivity to light olefins and longer lifetime in the MTO reaction. This work provides a convenient route to the synthesis of ZSM-5/SAPO-34 zeolite composites with excellent MTO performance.
研究领域:
化学工程
·
材料科学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2021
·Vol. 11
·期 4
·1952-1959
·
IF 3.361
Yi Zhao,Fangfang Peng,Yangchuan Ke
The application of nanotechnology in the oil and gas industry has attracted widespread attention in recent years. This study aims to develop a nanoemulsion (NE) for use in enhanced oil recovery (EOR). The NE stabilized by anion amphiphilic copolymer, nonionic surfactant (Brij30) and modified LAPONITE® RD was prepared by the phase inversion composition (PIC) method. The appearance of the emulsion is translucent and the average particle size is less than 60 nm. The micromorphology and interfacial tension (IFT) are examined using transmission electron microscopy (TEM) and a spinning drop IFT meter, respectively. The NE possesses good stability evaluated by conductivity and particle size tests. The absolute value of the zeta potential of NE increases when modified LAPONITE® RD is added. In a core flooding experiment with an artificial sandstone core, the NE flooding increased oil recovery by 23.53% compared to water flooding.
研究领域:
石油工程
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纳米技术
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 49
·43663-43671
·
IF 3.289
Changpeng Li,Changdao Mu,Wei Lin
Methacrylated gelatin (MA-gelatin) is a gelatin derivative synthesized by the reaction with methacrylic anhydride; the degree of substitution (DS) of primary amines by methacrylamide groups in the gelatin is closely related to the dosage of methacrylic anhydride. In this work, MA-gelatin has been developed as a macromolecular crosslinker to prepare novel nanocomposite hydrogels (NC gels) based on polyacrylamide (PAAm) and LAPONITE® nanoclay. Compared with unmodified gelatin, MA-gelatin improves the stability of the LAPONITE® suspension in the pre-gel system. FTIR results confirm the success of gelatin modification, in agreement with the 1H NMR result, and the copolymerization of MA-gelatin and acrylamide monomers in the NC gel network. The increasing DS of MA-gelatin thus reduces the equilibrium swelling ratio (ESR) and pore sizes, and enhances the mechanical properties of the NC gels, due to the macromolecular crosslinking effect. Unlike the small molecular crosslinker N,N′-methylenebisacrylamide (BIS), MA-gelatin shows a stronger influence on the swelling behaviours and mechanical properties of NC gels. Moreover, the MA-gelatin crosslinked NC gels exhibit decreased bovine serum albumin (BSA) adsorption, prolonged blood-clotting time and nonhemolytic nature, indicating the improved antithrombogenicity. The results show that MA-gelatin can be a hemocompatible macromolecular crosslinker for the fabrication of biomedical materials.
研究领域:
生物材料
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组织工程
·
医学工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2023
·
IF 8.2
Chen Yu,Xinlai Dou,Linghan Meng,Xiao Feng,Chengcheng Gao,Fenglian Chen,Xiaozhi Tang
Hydrogels, owing to their unique porous structures, hydrophilic properties, and biocompatibility, are being developed as scaffolds for bone grafts. However, the use of toxic initiators or cross-linking agents is a drawback. To overcome this, we developed Laponite®/cross-linked starch/polyvinyl alcohol (PVA) hydrogels prepared by one-step solution mixing. The structure, rheological properties, and biocompatibility of the hydrogels were investigated. Zeta potential , Fourier transform infrared, and X-ray diffraction analyses showed that hydrogen bonding and electrostatic interactions jointly maintained the structure of the cross-linked hydrogel systems. At a Laponite® concentration of 10 %, the hydrogel with a starch/PVA ratio of 2:2 exhibited a uniform porous structure, the highest storage modulus (G'), and the lowest degradation rate. At a starch/PVA ratio of 2:2, the G' increased; however, the degradation rate decreased with the increase in Laponite® content from 5 % to 20 %. These results indicate that the mechanical strength and degradation rate of the hydrogels could be adjusted by altering the starch/PVA ratio and the amount of Laponite®. In vitro cytotoxicity experiments showed that the Laponite®/starch/PVA (LSP) hydrogels were non-toxic to MC3T3-E1 cells. The starch/PVA ratio had no obvious effect on the proliferation of MC3T3-E1 cells, but an increase in Laponite® content significantly promoted cell proliferation . In summary, the results suggest that these LSP hydrogels have great potential for applications in bone tissue engineering.
✓ 已验证
DOI
PubMed
高影响因子
Soft Matter
·
2020
·Vol. 16
·期 36
·8394-8399
·
IF 3.14
Xinyu Liu,Xiaofeng Niu,Zhinan Fu,Liqun Liu,Shengyu Bai,Jie Wang,Li Li,Yiming Wang,Xuhong Guo
LAPONITE® sheets have been widely used for the preparation of tough nanocomposite hydrogels for enticing applications; however, their inferior dispersion in aqueous media resulting from electrostatic interactions between the nanosheets remarkably limits further improvements in the mechanical performances of the nanocomposite hydrogels. Here, we show a simple approach to dramatically accelerate the dispersion of LAPONITE® sheets in water, and in turn further improve the mechanical performances of the resulting nanocomposite hydrogels. Upon addition of poly(acrylic acid) (PAA), the electrostatic interactions between the LAPONITE® sheets were effectively reduced due to the adsorption of PAA onto the positively charged edges of the LAPONITE® sheets, thereby accelerating the dispersion of the LAPONITE® sheets in water. On this basis, a series of polyacrylamide (PAAm) hydrogels with a high content of LAPONITE® sheets was prepared, showing excellent tensile strength, stretchability, and anti-fatigue properties. This study will be beneficial for the preparation of LAPONITE®-based nanocomposite hydrogels bearing excellent mechanical properties for new applications.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry B
·
2018
·Vol. 6
·期 30
·5011-5020
·
IF 4.776
Jinyu Li,Yue Yang,Yibin Yu,Qi Li,Guoxin Tan,Yuanyuan Wang,Wei Liu,Weisan Pan
The synthetic clay material, LAPONITE® (LAP), having a nanodisk structure together with a negatively charged surface, has been used for effective drug encapsulation by virtue of its interlayer space. In this research effort, the LAP nanodisk was used for the first time to encapsulate the antifolic methotrexate (MTX); the MTX-loaded LAP nanodisks (LAP/MTX) demonstrated a high drug loading efficiency of 80.39%. An efficient and reliable tumor-targeting device that rests on the synthesized oligomeric hyaluronic acid-L-histidine (oHA–His) was then encapsulated in the MTX-loaded LAP disks (forming LAP/MTX/oHA–His nanohybrids). The drug released from the LAP/MTX/oHA–His nanohybrids was pH-dependent and matched the first-order kinetics that describes the diffusion mechanism. In vitro biological evaluation manifested that the MTX-loaded LAP nanocarriers, particularly the LAP/MTX/oHA–His nanohybrids that have targetability and lysosomal antineoplastic activity, can be effectively internalized by the MCF-7 cell line, and can exhibit a more prominent anticancer cytotoxicity than free MTX. In vivo studies with mice indicated that the LAP/MTX/oHA–His nanohybrids demonstrated much higher antitumor efficiency compared to the LAP/MTX nanohybrids and pure MTX. Taken together, the LAP/oHA–His, CD44 receptor targeting and pH-sensitive multifunctional nanohybrids conferred the MTX with excellent cytocompatibility, dispersion stability, sustained pH-responsive release properties, and improved anticancer activity, and may be further developed as a potential active nanoplatform for various anticancer drugs.
研究领域:
药学
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纳米技术
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癌症研究
·
药物递送系统
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2021
·Vol. 11
·期 52
·32988-32995
·
IF 3.361
Yinlei Lin,Shuoqi Wang,Sheng Sun,Yaoheng Liang,Yisheng Xu,Huawen Hu,Jie Luo,Haichen Zhang,Guangji Li
Introducing double physical crosslinking reagents (i.e., a hydrophobic monomer micelle and the LAPONITE® XLG nano-clay) into the copolymerization reaction of hydrophilic monomers of N,N-dimethylacrylamide (DMAA) and acrylamide (AM) is reported here by a thermally induced free-radical polymerization method, resulting in a highly tough and rapid self-healing dual-physical crosslinking poly(DMAA-co-AM) hydrogel. The mechanical and self-healing properties can be finely tuned by varying the weight ratio of nanoclay to DMAA. The tensile strength and elongation at break of the resulting nanocomposite hydrogel can be modulated in the range of 7.5–60 kPa and 1630–3000%, respectively. Notably, such a tough hydrogel also exhibits fast self-healing properties, e.g., its self-healing rate reaches 48% and 80% within 2 and 24 h, respectively.
研究领域:
材料科学
·
高分子化学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）