期刊文献+
共找到727篇文章
< 1 2 37 >
每页显示 20 50 100
Effects of Polyethylene Oxide Concentration on the Size of Beads in Electrospun Beaded Nanofibers 被引量:5
1
作者 张媛 李庭晓 +2 位作者 丁辛 胡吉永 杨旭东 《Journal of Donghua University(English Edition)》 EI CAS 2014年第4期511-514,共4页
Embedding particle drugs in beaded nanofibers by electrospinning has been shown a potential approach to control drug release in tissue engineering. The bead size is one of the critical parameters in controlling the dr... Embedding particle drugs in beaded nanofibers by electrospinning has been shown a potential approach to control drug release in tissue engineering. The bead size is one of the critical parameters in controlling the drug release rate. In this study,the relationship between polymer concentration and beads size was investigated. Aqueous polyethylene oxide( PEO) solutions with different concentrations were prepared to obtain various beaded nanofibers by electrospnning. Optical microscope and scanning electron microscope( SEM) were used to observe the variation tendency of bead size. With an increase in the polymer concentration,the diameter of fibers between beads became bigger,while the fiber uniformity improved. In addition, the polymer concentration influenced the distribution of bead diameter. Higher polymer concentration would reduce the possibility of small-sized beads formation and improve the uniformity of bead diameter. The study provides a possible way to control the size of beads,which is helpful for further research on the control of particle drug release. 展开更多
关键词 electrospinning beaded nanofiber CONCENTRATION polyethylene oxide(peo) bead size
下载PDF
Incorporating multifunctional LiAlSiO_(4) into polyethylene oxide for high-performance solid-state lithium batteries 被引量:4
2
作者 Yuqi Wu Xinhai Li +6 位作者 Guochun Yan Zhixing Wang Huajun Guo Yong Ke Lijue Wu Haikuo Fu Jiexi Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第2期116-123,I0005,共9页
High ionic conductivity,good electrochemical stability,and satisfactory mechanical property are the crucial factors for polymer solid state electrolytes.Herein,fast ion conductor LiAlSiO_4(LASO) is incorporated into p... High ionic conductivity,good electrochemical stability,and satisfactory mechanical property are the crucial factors for polymer solid state electrolytes.Herein,fast ion conductor LiAlSiO_4(LASO) is incorporated into polyethylene oxide(PEO)-based solid-state electrolytes(SSEs).The SSEs containing LASO exhibit enhanced mechanical properties performance compared to pristine PEO-LiTFSI electrolyte.A reduced melting transition temperature of 40.57℃ is enabled by introducing LASO in to PEO-based SSE,which is beneficial to the motion of PEO chain and makes it possible for working at a moderate environment.Coupling with the enhanced motion of PEO,dissociation of the lithium salt,and conducting channel of LASO,the optimized composite polymer SSE exhibits a high ionic conductivity of 4.68×10^(-4),3.16×10^(-4) and 1.62×10^(-4) S cm^(-1) at 60,50 and 40℃,respectively.The corresponding LiFePO_4//Li solid-state battery exhibits high specific capacities of 166,160 and 139 mAh g^(-1) at 0.2 C under 60,40 and 25℃.In addition,it remains 130 mAh g^(-1) at 4.0 C,and maintains 91.74% after 500 cycles at 1.0 C under 60℃.This study provides a simple approach for developing ionic conductor-filled polymer electrolytes in solid-state lithium battery application. 展开更多
关键词 LiAlSiO_(4) polyethylene oxide Solid state battery Composite polymer electrolyte Ionic conductivity
下载PDF
Polyethylene glycol radical-initiated aerobic propargylic oxidation in dense carbon dioxide 被引量:1
3
作者 Zhenfeng Diao Bin Li +2 位作者 Bing Yu Anhua Liu Liangnian He 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2013年第3期363-367,共5页
The selective aerobic oxidation of alkynes to corresponding α,β-acetylenic ketones was achieved in polyethylene glycol/dense CO2/O2 biphasic system without any catalyst or additive. The effects of reaction parameter... The selective aerobic oxidation of alkynes to corresponding α,β-acetylenic ketones was achieved in polyethylene glycol/dense CO2/O2 biphasic system without any catalyst or additive. The effects of reaction parameters, e.g. temperature, CO2 pressure, PEG molecular weight and loading on the reaction were carefully examined. Moreover, various substrates worked well in the presence of PEG 1000 under 5 MPa of CO2 and 2 MPa of O2 at 100 ℃ for 12 to 24 h and acceptable yield and selectivity could be obtained in most cases. Preliminary mechanistic investigations were also discussed. 展开更多
关键词 carbon dioxide polyethylene glycol selective oxidation ALKYNES β-acetylenic ketones
下载PDF
Pediatric bowel preparation: Sodium picosulfate, magnesium oxide, citric acid vs polyethylene glycol, a randomized trial 被引量:1
4
作者 Carmen Cuffari Steven L Ciciora +2 位作者 Masakazu Ando Mena Boules Joseph M Croffie 《World Journal of Gastroenterology》 SCIE CAS 2020年第40期6260-6269,共10页
BACKGROUND Bowel preparation in children can be challenging.AIM To describe the efficacy, safety, and tolerability of sodium picosulfate, magnesium oxide, and citric acid(SPMC) bowel preparation in children.METHODS Ph... BACKGROUND Bowel preparation in children can be challenging.AIM To describe the efficacy, safety, and tolerability of sodium picosulfate, magnesium oxide, and citric acid(SPMC) bowel preparation in children.METHODS Phase 3, randomized, assessor-blinded, multicenter study of low-volume, divided dose SPMC enrolled children 9-16 years undergoing elective colonoscopy. Participants 9-12 years were randomized 1:1:1 to SPMC ? dose × 2, SPMC 1 dose × 2, or polyethylene glycol(PEG). Participants 13-16 years were randomized 1:1 to SPMC 1 dose × 2 or PEG. PEG-based bowel preparations were administered per local protocol. Primary efficacy endpoint for quality of bowel preparation was responders(rating of ‘excellent' or ‘good') by modified Aronchick Scale. Secondary efficacy endpoint was participant's tolerability and satisfaction from a 7-item questionnaire. Safety assessments included adverse events(AEs) and laboratory evaluations.RESULTS 78 participants were randomized, 48 were 9-12 years, 30 were 13-16 years. For the primary efficacy endpoint in 9-12 years, 50.0%, 87.5%, and 81.3% were responders for SPMC ? dose × 2, SPMC 1 dose × 2, and PEG groups, respectively. Responder rates for 13-16 years were 81.3% for SPMC 1 dose × 2 and 85.7% for PEG. Overall, 43.8% of participants receiving SPMC 1 dose × 2 reported it was ‘very easy' or ‘easy' to drink, compared with 20.0% receiving PEG. Treatment-emergent AEs were reported by 45.5% of participants receiving SPMC 1 dose × 2 and 63.0% receiving PEG.CONCLUSION SPMC was an efficacious and safe for bowel preparation in children 9-16 years, with comparable efficacy to PEG. Tolerability for SPMC was higher compared to PEG. 展开更多
关键词 CHILDREN COLONOSCOPY Colon cleansing Sodium picosulfate magnesium oxide and citric acid polyethylene glycol
下载PDF
DEPOLYMERIZATION AND KINETICS OF DEPOLYMERIZATION OF POLYETHYLENE TEREPHTHALATE USING DIBUTYLTIN OXIDE CATALYST
5
作者 T.Naruephat D.Somsak +1 位作者 V.Tharapong P.Amorn 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2006年第2期139-145,共7页
Depolymerization of poly(ethylene terephthalate) (PET) was performed in the tubular bomb microreactor which contained the solution of PET in methanol and dibutyltin oxide at the temperature ranging from 433 K to 4... Depolymerization of poly(ethylene terephthalate) (PET) was performed in the tubular bomb microreactor which contained the solution of PET in methanol and dibutyltin oxide at the temperature ranging from 433 K to 473 K, the reaction time from 5 to 45 min and the catalyst-to-PET ratio of 0.3%-2% by weight. The optimal condition for PET depolymerization catalyzed by dibutyltin oxide is the temperature of 443-453 K, the reaction time of 20-25 min and 0.8% by weight of catalyst. By using differential methods, the activation energy for the depolymerization process was found to be 154.05 kJ/mol in the temperature range from 433-463 K. 展开更多
关键词 DEPOLYMERIZATION polyethylene terephthalate Dibutyltin oxide DEGRADATION KINETICS
下载PDF
PEO/rGO复合电热膜的制备及电热性能研究
6
作者 张丽辉 郭锐 +3 位作者 刘亚宁 王冰佳 童博 夏阳 《化工新型材料》 CAS CSCD 北大核心 2024年第6期83-88,93,共7页
采用导电性能优异的还原氧化石墨烯(rGO)为导电填料,以高分子聚合物聚氧化乙烯(PEO)为粘结剂,以N-甲基-2-吡咯烷酮(NMP)为溶剂配制成导电浆料,通过刮涂法高温固化得到聚氧化乙烯/还原氧化石墨烯(PEO/rGO)复合电热膜。通过X射线衍射仪、... 采用导电性能优异的还原氧化石墨烯(rGO)为导电填料,以高分子聚合物聚氧化乙烯(PEO)为粘结剂,以N-甲基-2-吡咯烷酮(NMP)为溶剂配制成导电浆料,通过刮涂法高温固化得到聚氧化乙烯/还原氧化石墨烯(PEO/rGO)复合电热膜。通过X射线衍射仪、扫描电子显微镜、傅里叶变换红外光谱仪对复合电热膜进行分析表征,并测试了其电学特性和电加热性能。结果表明:PEO/rGO复合电热膜的方阻随着rGO含量的增加而逐渐下降,且方阻的下降速度由快到慢;PEO/rGO复合电热膜的升温速度随着导电填料rGO含量的增加逐渐变缓;当rGO含量较多、PEO含量较少时,会造成升温速率下降,也会造成电热平台不稳定;当rGO质量分数为20%时,在施加18V直流电压下复合电热膜可快速升温至43℃,并且表现出平稳的电热平台和较高的电加热效率,能够满足低温高效率复合电热膜的使用要求。 展开更多
关键词 聚氧化乙烯 还原氧化石墨烯 电热膜 复合材料
下载PDF
Ionic conductivity study on electron beam irradiated polyacrylonitrile-polyethylene oxide gel
7
作者 马艺准 庞立龙 +2 位作者 朱亚滨 王志光 申铁龙 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第7期466-471,共6页
Different mass percent polyacrylonitrile (PAN)-polyethylene oxide (PEO) gels were prepared and irradiated by an electron beam (EB) with energy of 1.0 MeV to the dose ranging from 13 kGy to 260 kGy. The gels were... Different mass percent polyacrylonitrile (PAN)-polyethylene oxide (PEO) gels were prepared and irradiated by an electron beam (EB) with energy of 1.0 MeV to the dose ranging from 13 kGy to 260 kGy. The gels were analysed by using Fourier transform infrared spectrum, gel fraction and ionic conductivity (IC) measurement. The results show that the gel is crosslinked by EB irradiation, the crosslinking degree rises with the increasing EB irradiation dose (ID) and the mass percents of both PAN and PEO contribute a lot to the crosslinking; in addition, EB irradiation can promote the IC of PAN-PEO gels. There exists an optimum irradiation dose, at which the IC can increase dramatically. The IC changes of the PAN-PEO gels along with ID are divided into three regions: IC rapidly increasing region, IC decreasing region and IC balanced region. The cause of the change can be ascribed to two aspects, gel capturing electron degree and crosslinking degree. By comparing the IC-ID curves of different mass percents of PAN and PEO in gel, we found that PAN plays a more important role for gel IC promotion than PEO, since addition of PAN in gel causes the IC-ID curve sharper, while addition of PEO in gel causes the curve milder. 展开更多
关键词 POLYACRYLONITRILE polyethylene oxide electron beam irradiation ionic conductivity
下载PDF
Analytical method development of pregabalin and related substances in extended release tablets containing polyethylene oxide
8
作者 Jin Seob Oh Seo Hyun Lim +4 位作者 Sung Ha Ryu Kyung Hun Kim Kyung Soo Lee Woo Heon Song Jun Sang Park 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2016年第1期229-230,共2页
Pregabalin,(S)-3-amino methyl hexanoic acid,is a structural analogue ofγ-amino butyric acid(GABA)which has been widely used to treat partial seizures and neuropathic pain[1].It is soluble in aqueous solution and spar... Pregabalin,(S)-3-amino methyl hexanoic acid,is a structural analogue ofγ-amino butyric acid(GABA)which has been widely used to treat partial seizures and neuropathic pain[1].It is soluble in aqueous solution and sparingly soluble in organic solvents such as ethanol,DMSO and DMF.Polyethylene oxide(PEO)has a strong negative effect on analysis of hydrophilic active ingredient and its relative substances due to extremely high viscosity of PEO in aqueous media.The aim of this study is to develop a fast and precise method for the determination of pregabalin and its relative substances in extended release tablets including PEO using sodium sulfate for the treatment of sample solution. 展开更多
关键词 PREGABALIN polyethylene oxide Related COMPOUND HPLC
下载PDF
Flow Curves in the Centered Cylindrical Couette Geometry of a Polyethylene Oxide Solution
9
作者 Ngargoto Ngarmoundou Rilengar Godfroyd Ousman +1 位作者 Barka Mahamat Aboubaker Chedikh Beye 《Open Journal of Fluid Dynamics》 2017年第4期673-695,共23页
Polyethylene oxide solutions have a behavioral flexibility that provides researchers with the opportunity to use constitutive law models in a variety of ways for their MRI characterization. Our results obtained in num... Polyethylene oxide solutions have a behavioral flexibility that provides researchers with the opportunity to use constitutive law models in a variety of ways for their MRI characterization. Our results obtained in numerical simulation carried out in 2D and 3D for speed profiles of a solution of PEO deployed by the simple method of the cylindrical Couette geometry considering the fluid Newtonian defect, allowed to identify the behavior of fluid complex (rheo-fluidifying threshold fluid). The relevance and the interest of the method are examined by analyzing these results generated by the numerical data obtained, since these profiles depend on the non-Newtonian properties of the fluid which one does not know a priori and which one seeks to measure by postulating first to the power law of Ostwald, then to the truncated power law. 展开更多
关键词 RHEOLOGY Behavior polyethylene oxide COUETTE GEOMETRY Viscosity Speed Profiles SHEAR Stress SHEAR BANDS SHEAR Rate Localization Rheo-Fluidifying Threshold
下载PDF
Factors Affecting Fines Flocculation Performance with Cofactor-Polyethylene Oxide
10
作者 M. R. Abdallah Qasaimeh Ahmad Qasaimeh F. Bani Hani 《Advances in Chemical Engineering and Science》 2014年第1期49-55,共7页
In literature, neutral polyethylene oxide (PEO) flocculated fines at low shear rates, while with cofactor (CF) addition, the formed CF-PEO complex showed larger ability to bridge fines, producing flocs. In this work, ... In literature, neutral polyethylene oxide (PEO) flocculated fines at low shear rates, while with cofactor (CF) addition, the formed CF-PEO complex showed larger ability to bridge fines, producing flocs. In this work, some process factors were found having significant effects on fines flocculation. Increases in CF to PEO ratio at constant PEO enhanced the bridging bonds, causing increases in flocculation initial rate (efficiency), amplitude (floc size), and fastness (a decrease in characteristic time). On the other hand, an increase in stirring rate (shear rate) in flocculation vessel caused decreases in initial rate and amplitude, and an increase in the fastness. All runs showed transient flocculation;the amplitude increased with time, reached maximum at equilibrium, and then started to decrease showing deflocculation. In brief, the CF to PEO ratio and the shear rate were found important parameters in mill operation, having significant effects on flocculation efficiency, fastness, and floc size. 展开更多
关键词 polyethylene oxide COFACTOR FLOCCULATION SHEARING and BRIDGING
下载PDF
High-Density Polyethylene Based on Exfoliated Graphite Nanoplatelets/Nano-Magnesium Oxide: An Investigation of Thermal Properties and Morphology
11
作者 A. I. Alateyah 《Materials Sciences and Applications》 2019年第3期159-169,共11页
In this study, high-density polyethylene (HDPE)/exfoliated graphite nanoplatelet (xGnP) composites reinforced with a 2 wt.% concentration of nano-magnesia (n-MgO) were fabricated using an injection moulding machine. T... In this study, high-density polyethylene (HDPE)/exfoliated graphite nanoplatelet (xGnP) composites reinforced with a 2 wt.% concentration of nano-magnesia (n-MgO) were fabricated using an injection moulding machine. The thermal properties and morphological structures of the composites were investigated. The XRD results showed the peaks of xGnP and n-MgO, where the intensity of the xGnP peaks became stronger with adding increasing amounts of xGnP into the polymermatrix. In terms of morphology, some agglomeration of particles was observed within the matrix, and the agglomeration decreased the thermal properties of the composites. The nanocomposites showed less thermal stability than the pristine polymer. The reduction in the onset temperature compared to that of neat HDPE was attributed to less adhesion between the fillers and the matrix. In addition, the crystallinity was reduced by the addition of fillers. 展开更多
关键词 HIGH-DENSITY polyethylene EXFOLIATED GRAPHITE NANOPLATELETS Magnesium oxide Nanoparticles TGA XRD SEM
下载PDF
Advancements in enhancing corrosion protection of Mg alloys:A comprehensive review on the synergistic effects of combining inhibitors with PEO coating
12
作者 Arash Fattah-alhosseini Abdelhameed Fardosi +1 位作者 Minoo Karbasi Mosab Kaseem 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第2期465-489,共25页
Magnesium(Mg)alloys are lightweight materials with excellent mechanical properties,making them attractive for various applications,including aerospace,automotive,and biomedical industries.However,the practical applica... Magnesium(Mg)alloys are lightweight materials with excellent mechanical properties,making them attractive for various applications,including aerospace,automotive,and biomedical industries.However,the practical application of Mg alloys is limited due to their high susceptibility to corrosion.Plasma electrolytic oxidation(PEO),or micro-arc oxidation(MAO),is a coating method that boosts Mg alloys'corrosion resistance.However,despite the benefits of PEO coatings,they can still exhibit certain limitations,such as failing to maintain long-term protection as a result of their inherent porosity.To address these challenges,researchers have suggested the use of inhibitors in combination with PEO coatings on Mg alloys.Inhibitors are chemical compounds that can be incorporated into the coating or applied as a post-treatment to further boost the corrosion resistance of the PEO-coated Mg alloys.Corrosion inhibitors,whether organic or inorganic,can act by forming a protective barrier,hindering the corrosion process,or modifying the surface properties to reduce susceptibility to corrosion.Containers can be made of various materials,including polyelectrolyte shells,layered double hydroxides,polymer shells,and mesoporous inorganic materials.Encapsulating corrosion inhibitors in containers fully compatible with the coating matrix and substrate is a promising approach for their incorporation.Laboratory studies of the combination of inhibitors with PEO coatings on Mg alloys have shown promising results,demonstrating significant corrosion mitigation,extending the service life of Mg alloy components in aggressive environments,and providing self-healing properties.In general,this review presents available information on the incorporation of inhibitors with PEO coatings,which can lead to improved performance of Mg alloy components in demanding environments. 展开更多
关键词 INHIBITOR Mg alloy Self-healing coating Plasma electrolytic oxidation(peo) Corrosion protection
下载PDF
In-situ polymerized PEO-based solid electrolytes contribute better Li metal batteries:Challenges,strategies,and perspectives
13
作者 Zhihui Jia Yong Liu +4 位作者 Haoming Li Yi Xiong Yingjie Miao Zhongxiu Liu Fengzhang Ren 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期548-571,共24页
Polyethylene oxide(PEO)-based solid polymer electrolytes(SPEs)with good electrochemical stability and excellent Li salt solubility are considered as one of the most promising SPEs for solid-state lithium metal batteri... Polyethylene oxide(PEO)-based solid polymer electrolytes(SPEs)with good electrochemical stability and excellent Li salt solubility are considered as one of the most promising SPEs for solid-state lithium metal batteries(SSLMBs).However,PEO-based SPEs suffer from low ionic conductivity at room temperature and high interfacial resistance with the electrodes due to poor interfacial contact,seriously hindering their practical applications.As an emerging technology,in-situ polymerization process has been widely used in PEO-based SPEs because it can effectively increase Li-ion transport at the interface and improve the interfacial contact between the electrolyte and electrodes.Herein,we review recent advances in design and fabrication of in-situ polymerized PEO-based SPEs to realize enhanced performance in LMBs.The merits and current challenges of various SPEs,as well as their stabilizing strategies are presented.Furthermore,various in-situ polymerization methods(such as free radical polymerization,cationic polymerization,anionic polymerization)for the preparation of PEO-based SPEs are summarized.In addition,the application of in-situ polymerization technology in PEO-based SPEs for adjustment of the functional units and addition of different functional filler materials was systematically discussed to explore the design concepts,methods and working mechanisms.Finally,the challenges and future prospects of in-situ polymerized PEO-based SPEs for SSLMBs are also proposed. 展开更多
关键词 In-situ polymerization polyethylene oxide Solid polymer electrolytes Lithium metal anodes
下载PDF
聚离子液体复合PEO制备高性能全固态聚合物电解质
14
作者 徐祖婧 赵相峰 《功能材料》 CAS CSCD 北大核心 2024年第1期1172-1178,共7页
用化学共沉淀法固态聚合物电解质(SPE)因其独特的安全性能受到越来越多的关注。以聚环氧乙烷(PEO)为基体,通过引入聚离子液体(PIL),制备了一种新型SPE(PIL@PEO SPE)。通过将PIL穿插于PEO链段中,有效降低了PEO的结晶度,提高了SPE的离子... 用化学共沉淀法固态聚合物电解质(SPE)因其独特的安全性能受到越来越多的关注。以聚环氧乙烷(PEO)为基体,通过引入聚离子液体(PIL),制备了一种新型SPE(PIL@PEO SPE)。通过将PIL穿插于PEO链段中,有效降低了PEO的结晶度,提高了SPE的离子电导率(6.63×10^(-4)S/cm)。由其制备的固态电池在0.5C,60℃时,Li/LiFePO4电池首次放电容量高达147.6 mAh/g,经过长达300圈充放电循环,容量保留率仍然在90%以上。 展开更多
关键词 固态聚合物电解质 聚离子液体 聚氧化乙烯 锂离子电池
下载PDF
原位复合法制备TiO_2/(PEO)_8LiClO_4聚合物电解质 被引量:7
15
作者 戴潇燕 潘春跃 +1 位作者 冯庆 巢猛 《复合材料学报》 EI CAS CSCD 北大核心 2006年第5期75-78,共4页
以聚氧化乙烯/高氯酸锂络合物((PEO)8LiClO4)为基体,通过钛酸四丁酯的水解缩合反应在基体中原位生成TiO2粒子,制备了TiO2/(PEO)8LiClO4复合聚合物电解质膜。采用SEM、DSC和交流阻抗方法分别研究了电解质膜的表面形貌、热性能和离子导电... 以聚氧化乙烯/高氯酸锂络合物((PEO)8LiClO4)为基体,通过钛酸四丁酯的水解缩合反应在基体中原位生成TiO2粒子,制备了TiO2/(PEO)8LiClO4复合聚合物电解质膜。采用SEM、DSC和交流阻抗方法分别研究了电解质膜的表面形貌、热性能和离子导电性能。结果表明,原位生成的TiO2粒子均匀分散于PEO基体中。复合TiO2后电解质膜的玻璃化转变温度和结晶度降低。电解质膜的离子导电行为满足Arrhenius方程,并在5%TiO2含量时体系的电导率出现最大值5.5×10-5S/cm(20℃)。以此膜为电解质组装的全固态聚合物锂电池放电时电压平稳,20次循环后放电容量保持在107 mAh/g。 展开更多
关键词 聚合物电解质 聚氧化乙烯(peo) TIO2 原位复合 电导率
下载PDF
聚氧化乙烯(PEO)的合成及应用 被引量:20
16
作者 崔凤霞 郭春梅 +2 位作者 王开林 崔连起 戴清文 《精细石油化工》 CAS CSCD 北大核心 1999年第6期41-44,共4页
介绍了 PEO的性质及合成机理 ,综述了合成 PEO的催化剂体系及其应用 ,展望了
关键词 催化剂 合成 聚氧化乙烯 peo
下载PDF
PEO-PPO-PEO水溶液体系胶束化及凝胶化行为的耗散粒子动力学模拟 被引量:7
17
作者 谢宇 吕中元 +1 位作者 孙昭艳 安立佳 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2013年第6期1454-1459,共6页
采用耗散粒子动力学(Dissipative particle dynamics,DPD)模拟方法研究了三嵌段共聚物聚氧乙烯-聚氧丙烯-聚氧乙烯(PEO-PPO-PEO)的胶束化和凝胶化行为.通过模拟得到了F127(EO99PO65EO99)水溶液的临界胶束浓度和临界凝胶浓度.结果发现,在... 采用耗散粒子动力学(Dissipative particle dynamics,DPD)模拟方法研究了三嵌段共聚物聚氧乙烯-聚氧丙烯-聚氧乙烯(PEO-PPO-PEO)的胶束化和凝胶化行为.通过模拟得到了F127(EO99PO65EO99)水溶液的临界胶束浓度和临界凝胶浓度.结果发现,在298 K、质量分数低于40%时,F127水溶液中形成的胶束形状均为球形.此外,进一步研究了亲水嵌段长度对胶束结构及凝胶形成浓度的影响,结果发现,亲水嵌段越短,越有利于长椭球状胶束的形成,而临界凝胶浓度随着亲水嵌段PEO长度的增加而降低. 展开更多
关键词 胶束化 凝胶化 聚氧乙烯-聚氧丙烯-聚氧乙烯 耗散粒子动力学
下载PDF
高角蛋白含量的角蛋白/PEO纳米纤维的制备及其性能表征 被引量:3
18
作者 刘雍 翟培羽 +3 位作者 雷通达 王永恒 曹福源 范杰 《天津工业大学学报》 CAS 北大核心 2016年第6期1-7,共7页
为探索以水为溶剂、由非交联改性角蛋白制备高角蛋白含量的角蛋白/PEO纳米纤维材料的方法,采用2-巯基乙醇/尿素/十二烷基硫酸钠混合体系提取高黏度人发角蛋白,将其与聚氧化乙烯(PEO)以不同质量分数混合,通过静电纺丝技术制备人发角蛋白/... 为探索以水为溶剂、由非交联改性角蛋白制备高角蛋白含量的角蛋白/PEO纳米纤维材料的方法,采用2-巯基乙醇/尿素/十二烷基硫酸钠混合体系提取高黏度人发角蛋白,将其与聚氧化乙烯(PEO)以不同质量分数混合,通过静电纺丝技术制备人发角蛋白/PEO纳米纤维并研究了其性能.结果表明:以巯基乙醇为还原剂提取的人发角蛋白溶液黏度较高,可以显著提高高比例角蛋白/PEO共混纺丝液的可纺性,制备的角蛋白/PEO纳米纤维的最大质量分数可达到80/20;随着角蛋白含量增加,纳米纤维平均直径逐渐减小,直径分布变窄,平均直径从310 nm(角蛋白/PEO=30/70)减小到82 nm(角蛋白/PEO=90/10);共混纳米纤维光谱中,酰胺Ⅰ带、酰胺Ⅱ带和酰胺Ⅲ带的吸收峰强度均逐渐增大,PEO在1 092.86 cm-1处的吸收峰强度逐渐减弱,角蛋白质量分数达到80%时,PEO在960 cm-1和841 cm-1处的吸收峰消失;角蛋白能够阻碍PEO的结晶过程,并使PEO的熔融峰向高温偏移,同时PEO能够阻止角蛋白的自组装而形成更为稳定的二级结构,从而提高了共混纳米纤维的热性能. 展开更多
关键词 人发角蛋白 聚氧化乙烯(peo) 纳米纤维 角蛋白含量
下载PDF
EAA增容LLDPE/PEO共混物及其增容机理 被引量:6
19
作者 徐胜清 唐涛 +1 位作者 黄葆同 殷翠梅 《化学学报》 SCIE CAS CSCD 北大核心 1998年第5期445-452,共8页
以乙烯-丙烯酸共聚物(EAA)为增容剂,研究了它在线性低密度聚乙烯(LLDPE)/聚环氧乙烷(PEO)共混物中的增容作用及其增容机理.采用电子显微镜(SEM)、动态力学分析(DMA)、DSC和红外光谱(IR)对共混物形态及其微观结构进行了表征结果表明,EAA... 以乙烯-丙烯酸共聚物(EAA)为增容剂,研究了它在线性低密度聚乙烯(LLDPE)/聚环氧乙烷(PEO)共混物中的增容作用及其增容机理.采用电子显微镜(SEM)、动态力学分析(DMA)、DSC和红外光谱(IR)对共混物形态及其微观结构进行了表征结果表明,EAA对LLDPE/PEO共混物有一定的增容作用;其增容机理为:EAA和LLDPE两者的非晶区部分相容,而EAA分子中的羧基与PEO分子中的醚氧基相互作用形成了分子间氢键. 展开更多
关键词 共混物 增容 聚乙烯 聚环氧乙烷 EAA LLDPE peo
下载PDF
红外光谱研究PEO基离子液体聚合物电解质 被引量:8
20
作者 金兰英 姜艳霞 +2 位作者 廖宏刚 曾冬梅 孙世刚 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2009年第4期767-771,共5页
以聚氧化乙烯(PEO)为聚合物基体,双三氟甲基磺酸亚酰胺锂(L iTFSI)为锂盐,加入不同量的离子液体(BM IMPF6)为增塑剂,制备离子液体聚合物电解质.运用发射FTIR光谱技术实时监测所制备聚合物电解质的结构随温度的变化.结合FTIR透射光谱、SE... 以聚氧化乙烯(PEO)为聚合物基体,双三氟甲基磺酸亚酰胺锂(L iTFSI)为锂盐,加入不同量的离子液体(BM IMPF6)为增塑剂,制备离子液体聚合物电解质.运用发射FTIR光谱技术实时监测所制备聚合物电解质的结构随温度的变化.结合FTIR透射光谱、SEM和XRD的研究结果分析了离子液体对离子电导率的影响,并初步提出离子导电增强机制. 展开更多
关键词 FTIR光谱 聚合物电解质 聚氧化乙烯 双三氟甲基磺酸亚酰胺锂 离子液体
下载PDF
上一页 1 2 37 下一页 到第
使用帮助 返回顶部