JOURNAL OF APPLIED POLYMER SCIENCE
·
2018
·Vol. 135
·期 23
·46351
·
IF 1.901
Li Wen,Liwen Wang,Shuyi Fang,Lei Bao,Dongdong Hu,Yuan Zong,Ling Zhao,Tao Liu
Two newly-designed hydrocarbon surfactants, that is, poly(vinyl acetate)- block -poly(1-vinyl-2-pyrrolidone) (PVAc- b -PVP) and PVP- b -PVAc- b -PVP, were synthesized using reversible addition–fragmentation chain transfer polymerization and used to form CO 2 /water (C/W) emulsions with high internal phase volume and good stability against flocculation and coalescence up to 60 h. Their structures were precisely determined by nuclear magnetic resonance, gel permeation chromatography, thermal gravimetric analysis, and differential scanning calorimetry. Besides low temperature and high CO 2 pressure, the surfactant structures were the key factors affecting the formation and stability of high internal phase C/W emulsions, including the polymerization degrees of CO 2 -philic block (PVAc) and hydrophilic block (PVP), as well as the number of hydrophilic tail. The surface tension of the surfactant aqueous solution and the apparent viscosity of the C/W emulsions were also measured to characterize the surfactants efficiency and effectiveness. The surfactants with double hydrophilic tails showed stronger emulsifying ability than those with single hydrophilic tail. The great enhancement of the emulsions stability was due to decrease of the interface tension as well as increase of the steric hindrance in the water lamellae, preventing a frequent collision of CO 2 droplets and their fast coalescence. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135 , 46351.
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
CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Yongyang Zhu,Shaoyang Shen,Liuzhang Ouyang,Jiangwen Liu,Hui Wang,Zhenguo Huang,Min Zhu
Magnesium borohydride (Mg(BH 4 ) 2 ) is widely regarded as a promising hydrogen storage material due to its high capacity; however, it is still challenging to synthesize Mg(BH 4 ) 2 with low cost. Traditionally, Mg(BH 4 ) 2 has been mainly produced using other borohydride as the starting materials via exchange reactions. Herein, we report an economical method to synthesize Mg(BH 4 ) 2 by converting B-O bonds in widely available borates or boric acid to B-H. The borates or boric acid is ball-milled with MgH 2 under ambient conditions to form Mg(BH 4 ) 2 with high yield (>80%). Mg(BH 4 ) 2 was also successfully generated by reacting low-cost Mg with boric acid. Compared with previous approaches, this method avoids expensive boron sources such as LiBH 4 , NaBH 4 , and B 2 H 6 , and does not require high pressure H 2 gas and high temperatures, and therefore significantly reduces costs. This method could be an alternative to the current Mg(BH 4 ) 2 synthesis processes.
研究领域:
材料科学
·
化学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY
·
2021
·Vol. 21
·期 4
·2174-2184
·
IF 0
Zhang Diansen,Xia Yuzheng,Gong Hongliang,Zhang Dong,Chen Xiaonong,Shi Shuxian,Lei Lei
Polylactide-b-poly(N-isopropylacrylamide)-b-polystyrene (PLA-b-PNIPAM-b-PS) triblock copolymers (tri-BCPs) with various chemical compositions (block ratio) were prepared from the combination of ring-opening polymerization and reversible addition-fragmentation
chain transfer polymerization. Subsequently, the self-assembling behaviors of these tri-BCP films obtained from spin-coating were investigated by annealing them under different solvent atmosphere. We found that these films could self-assemble into various morphologies due to the microphase
separation of incompatible copolymer blocks. Atomic force microscopy confirmed the perpendicular cylindrical morphology self-assembled from PLA4.5k-b-PNIPAM5.2k-b-PS22.4k tri-BCP film under mixed solvent atmosphere of toluene/acetone (7:3, v/v).
Self-assembled PLA cylinders are evenly distributed among the PS matrix and perpendicular to the film surface, with PNIPAM component taking place at the PLA/PS interphase. Furthermore, by etching the degradable PLA component, porous PS film decorated with PNIPAM “brushes” hoisting
channels were generated. This work provides a facile method and detailed protocol for fabricating stimuli-responsive porous films which are promising for thermoresponsive “smart” separation technologies.
研究领域:
材料科学
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高分子化学
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纳米技术
✓ 已验证
DOI
PubMed
JOURNAL OF BIOMATERIALS APPLICATIONS
·
2016
·
IF 1.988
Feng Xu,Jing-Wen Xu,Yan-Ling Luo
pH-Sensitive poly(methacrylic acid)-block-hydroxyl-terminated polybutadiene-block-poly(methacrylic acid) (PMAA-b-HTPB-b-PMAA) was synthesized and then hydrogenated in this work. The chain structure, phase behavior and thermal properties were characterized by 1H NMR, FTIR, XRD, DSC, TGA, etc., and the physicochemical and biomedical properties were investigated via fluorescence spectroscopy, TEM, DLS, loading and release of drug and MTT, and so on. The experimental results indicated that the hydrogenation led to the change in the chain aggregate structure of hydrophobic HTPB blocks and the formation of more stable spherical core-shell micelle aggregates, and the critical micelle concentration decreased from 41.8 mg L−1 before hydrogenation to 4.4 mg L−1 after hydrogenation. The hydrogenated block copolymer micelle aggregates exhibited pH-triggered response, and could entrap twice as much hydrophobic drug as the unhydrided counterparts and the encapsulation efficiency was significantly improved, which makes them fine to meet the requirements for drug carriers. Therefore, the hydrogenated PMAA-b-HTPB-b-PMAA copolymer micelles as drug target release carriers can be well used in the field of prevention and treatment of cancers.
研究领域:
材料科学
·
生物医学工程
·
药学
✓ 已验证
DOI
PubMed
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 127
·104907-104914
·
IF 3.84
Kunlin Chen,Shuxue Zhou,Limin Wu
Durability of nonfouling coatings is a critical problem to be solved for their practical application. In this paper, self-repairing nonfouling polyurethane (PU) coating was fabricated by spraying of a triblock copolymer of polyethylene glycol (PEG), 2-hydroxyethyl methacrylate (HEMA) and 2-methacryloyloxyethyl phosphorylcholine (MPC) on pre-cured acrylic-based PU coatings. The triblock copolymer was synthesized through living radical polymerization mediated by an atom transfer radical polymerization. Anchoring of the copolymer took place both on the surface and in the interior (namely, 3D-grafting) of PU coatings through the diffusion of the copolymer and subsequently the chemical reaction between the pendent hydroxyl group of the copolymer and the remaining isocyanate groups in the pre-cured PU coatings. This 3D grafting procedure is rather simple and favorable for large-area application. The 3D-grafted PU coating has higher hydrophilicity (water contact angle: 33°). In contrast, if the triblock copolymer was used as an additive in PU coatings, the hydrophilicity of the PU coating did not obviously change. The 3D-grafted PU coating effectively inhibited the adhesion of protein and human platelet cells due to the synergistic effect of PEG and MPC. Moreover, after the coatings were detached and mechanically damaged, the surfaces can restore their hydrophilicity and possess better long-term anti-fouling ability than the control surface-grafted coatings underwater.
研究领域:
材料科学
·
聚合物化学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2019
·Vol. 38
·期 3
·298-310
·
IF 2.804
Feng Cong-Shu,Chen Yun,Shao Jun,Li Gao,Hou Hao-Qing
In this study, the poly(D-lactide)-block-poly(butylene succinate)-block-poly(D-lactide) (PDLA- b -PBS- b -PDLA) triblock copolymers with a fixed length of PBS and various lengths of PDLA are synthesized, and the crystallization behaviors of the PDLA and PBS blocks are investigated. Although both the crystallization behaviors of PBS and PDLA blocks depend on composition, they exhibit different variations. For the PDLA block, its crystallization behaviors are mainly influenced by temperature and block length. The crystallization signals of PDLA block appear in the B-D 2–2 specimen, and these signals get enhanced with PDLA block length. The crystallization rates tend to decrease with increasing PDLA block lendth during crystallizing at 90 and 100 °C. Crystallizing at higher temperature, the crystallization rates increase at first and then decrease with block length. The crystallization rates decrease as elevating the crystallization temperature. The melting temperatures of PDLA blocks increase with block lengths and crystallization temperatures. For the PBS block, its crystallization behaviors are mainly controlled by the nucleation and confinement from PDLA block. The crystallization and melting enthalpies as well as the crystallization and melting temperatures of PBS block reduce as a longer PDLA block has been copolymerized, while the crystallization rates of the PBS block exhibit unique component dependence, and the highest rate is observed in the B-D 2–2 specimen. The Avrami exponent of PBS crystallites is reduced as a longer PDLA block is incorporated or the sample is crystallized at higher temperature. This investigation provides a convenient route to tune the crystallization behavior of PBS and PLA.
研究领域:
高分子化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2014
·Vol. 49
·期 22
·7730-7741
·
IF 2.305
Luo Yan-Ling,Huang Rui-Juan,Xu Feng,Chen Ya-Shao
pH-Sensitive biodegradable polymethacrylic acid- block -polylactic acid- block -polymethacrylic acid (PMAA 2 - b -PLA- b -PMAA 2 ) H-type multiblock copolymers were synthesized by atom transfer radical polymerization. The copolymer structure and molecular weight were characterized by FT-IR, 1 H NMR, and gel permeation chromatography. The physicochemical characterization revealed that the copolymers could spontaneously form spherical core–shell micelles in aqueous solution, with critical aggregation concentration of about 19.7–32.5 mg L −1 and the hydrodynamic diameters below 200 nm. Z eta potentials measurements disclosed that the copolymer micelles were negatively charged due to ionized carboxyl groups in various PBS solutions. The H-type block copolymer micelles exhibited pH- sensitivity, as expected; and the hydrophobic anticancer drugs, 10-hydroxycamptothecin, and paclitaxel, had faster release rate in PBS solution of pH 5.6–7.4 than in PBS of pH 1.4, which was important for applications in the therapy of small intestine cancers. The copolymer micelle aggregates were proved to be biodegradable, and the degradation rates changed with copolymer compositions and environmental media. The micelle drug formulation indicated pH-dependent cytotoxicity and was thus capable of effectively killing the intestinal cells while avoiding doing harm to stomach. The biodegradable pH-sensitive PMAA 2 - b -PLA- b -PMAA 2 H-type copolymer micelles can be used as water-insoluble drug targeting release carriers for targeted treatment of intestine cancers.
研究领域:
生物材料学
·
药剂学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2018
·
IF 4.439
Zhenglong Yang,Kangyu Fu,Jing Yu,Xujing Shi,Peiting Zhou,Zhihao Cheng
Polylactide-b-fullerene-b-poly(3-hexylthiophene) (PLA- b -C 60 - b -P3HT) triblock copolymer via a combination of 1,3-dipolar cycloaddition reaction and controlled ring-opening polymerization technique was successfully synthesized. The structure, morphology and crystallinity of PLA- b -C 60 - b -P3HT copolymer were characterized by 1 H NMR, GPC, DSC, TGA, XRD, UV–vis, PL and AFM measurements. Nanoporous C 60 /P3HT films were easily prepared from PLA- b -C 60 - b -P3HT triblock copolymer by casting the copolymer followed by thermal annealing and chemical etching of the PLA chains. Fullerene molecules could self-assembly between P3HT and PLA to form a continuous film. An ordered nanoporous C 60 /P3HT film was formed in AFM by chemically etching the PLA microphase with NaOH solution. Photoluminescence analysis showed that the photoinduced electron transfer of the ordered nanoporous C 60 /P3HT film was significantly improved compared to the physically blending sample due to the increased interface between the P3HT and the C 60 .
研究领域:
材料科学
·
有机光电材料
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2022
·
IF 10.53
Jian Ren,Xin Yang,Weixing Yan,Xia Feng,Yiping Zhao,Li Chen
The efficiency of the hemodialysis membrane has been widely improved by blending small molecular additives and modifying the membrane surface for patients with chronic or acute kidney disease. However, a qualified sieving property, flux, and hemocompatibility are intractable to give consideration simultaneously, while the elution of small-molecular additives and modifiers easily cause coagulation, complement activation, etc. Fortunately, the BCP methoxy polyethylene glycol-polyethersulfone-block-methoxy polyethylene glycol (mPEG -b- PES -b- mPEG) based membranes exhibiting great potential for sieving in middle molecular toxin and compatibility between mPEG -b- PES -b- mPEG and PES, is nearly unfeasible elution during hemodialysis, by reason of including bounded hydrophilic segments by chemical bonds. Here, the mPEG -b- PES -b- mPEG is synthesized to fabricate the membranes, including blend membranes and BCP membrane. As a result, the blend membranes have shown an increasing flux, hemocompatibility, and sieving of lysozyme with the increasing cooperation of mPEG-b-PES-b-mPEG, the block copolymer (BCP) mPEG -b- PES -b- mPEG membrane has shown better balance than the blend membranes in flux, sieving, and hemocompatibility. Besides, for exploring further possibilities, the typical blend membrane M4 (mPEG- b -PES- b -mPEG: 20%, PES: 5%) and BCP membrane M5 (mPEG- b -PES- b -mPEG: 25%) are post tailored by ethanol at 50 °C for 2 h. This process leading the typical membranes to an efficient flux (M5-P: 442.22 L m −2 h −1 ) and sieving performances (M5-P: the urea and lysozyme sieving of 96.43% and 74.97%) due to the effect of ethanol at the micro-molecular chain movements and microspheres transfer. Our work presents BCP mPEG -b- PES -b- mPEG a promising future in hemodialysis membranes according to the superior performances of flux and sieving.
研究领域:
材料科学
·
生物医学工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2023
·Vol. 16
·期 3
·1053
·
IF 3.4
Yanpei Dang,Tianhao Li,Yangzhong Zhao,Liantai Duan,Jianning Zhang,Ke Chen,Liu He,Qing Huang,Chuanzhuang Zhao,Yujie Song
Polyborosilazanes with controllable B/N ratio were synthesized using high-boron-contentm-carborane, dichloromethylsilane, and hexamethydisilazane. After high-temperature pyrolysis, Si–B–C–N quaternary ceramics with SiC and B4C as the main phases were obtained. The B/N ratio in the precursors corresponded to the change in the feeding ratio of carborane and dichloromethylsilane. The effects of boron content and B/N ratio on the ceramic precursors and microphase structure in Si–B–C–N quaternary ceramics were explored in detail through a series of analytical characterization methods. A high boron content results in a significant increase in the ceramic yield (up to 71 wt%) of polyborosilazanes, and at the same time, the B/N molar ratio was regulated from 28.4:1 to 1.62:1. The appearance of the B4C structure in the Si–B–C–N quaternary ceramics through the regulation of the B/N ratio, has rarely been reported.Keywords:polyborosilazane;SiBCN;carborane;polymer derived ceramics;B/N ratio;microphase evolution
研究领域:
材料科学
·
化学工程
·
陶瓷
✓ 已验证
产品关联
DOI
PubMed
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 27
·20890-20899
·
IF 3.84
Minghui Xu,Junmin Qian,Aili Suo,Weijun Xu,Rongrong Liu,Hongjie Wang
Combination of chemotherapy and small interfering RNA (siRNA)-based therapy has emerged as a promising approach for cancer treatment with the synergistic effect. In this study, a novel terpolymer methoxy poly(ethylene glycol)-block-poly(N,N-dimethylaminopropyl methacrylamide)-block-poly(acrylhydrazine) (mPEG-b-PDMAPMA-b-PAH) with a disulfide linkage between mPEG and PDMAPMA blocks was developed for the intracellular targeted co-delivery of adriamycin and P-gp siRNA. The terpolymer was synthesized by sequential reversible addition–fragmentation chain transfer (RAFT) polymerization of N,N-dimethylaminopropyl methacrylamide and N-tert-butoxycarbonyl-N′-acryl hydrazine (Boc-acrylhydrazine) in the presence of a PEGylated macro-RAFT agent, followed by Boc-deprotection. The terpolymer could chemically conjugate adriamycin via an acid-cleavable hydrazone bond and simultaneously condense the negatively charged siRNA through electrostatic interactions at an N/P ratio of 2. The resultant adriamycin-conjugated nanoparticles/siRNA complexes (ADR-NPs/siRNA complexes) showed a spherical morphology and had an average diameter of 186 nm. The release profiles of the two payloads from the ADR-NPs/siRNA complexes exhibited a pH/reduction dual-dependent sustained release behavior. The ADR-NPs/siRNA complexes could simultaneously deliver adriamycin and siRNA efficiently into MCF-7/ADR cells and significantly inhibit their growth in a synergistic fashion. All the results indicated that the terpolymer mPEG-b-PDMAPMA-b-PAH could serve as a potential vehicle for the combination of chemotherapy and gene therapy.
研究领域:
药学
·
纳米技术
·
癌症研究
·
聚合物化学
·
药物递送系统
✓ 已验证
产品关联
DOI
高影响因子
CHEMISTRY OF MATERIALS
·
2021
·
IF 9.811
Chuanzhou Han,Guoqi Ji,Sanlue Hu,Ruixiang Mi,Pengfei Fu,Ke-Zhao Du,Zewen Xiao
B-site rock-salt-ordered halide double perovskites have attracted significant attention for optoelectronic applications such as light-emitting diodes and photodetectors. Recently, B-site columnar-ordered halide perovskites A2B(I)B(II)X5 have been discovered as a new family of halide double perovskites, providing a new platform for exploring optoelectronic semiconductors. In this work, we report a new class of B-site columnar-ordered halide double perovskites A2B(II)′0.5B(II)X5, which are derived from the B-site columnar-ordered halide double perovskites A2B(I)B(II)X5 by replacing every two B(I) cations by one B(II)′ cation and one vacancy. Three examples, that is, Cs2Hg0.5PdCl5, Cs2Hg0.5PdBr5, and Cs2Hg0.5PtCl5 have been synthesized by a solvothermal method. The synthesized halide double perovskites crystallize into a tetragonal structure with space group P4/mmm, where the two nonequivalent crystallographic B-sites adopt the columnar ordering. The stoichiometric B(II)′ cations and vacancies are disorderly arranged on the equivalent octahedral B-sites. These halide double perovskites exhibit relatively small bandgaps of 1.93–2.05 eV and good air and thermal stability. This work further expands the family of B-site columnar-ordered halide double perovskites and provides guidance for theory-driven material exploration.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）