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阴离子型聚氨酯水分散体的合成及其在单组分水性素色漆中的应用 预览
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作者 张育波 周其运 +4 位作者 刘冬立 秦中海 雷晓进 严明辉 赵立英 《涂料工业》 CAS CSCD 北大核心 2019年第2期50-55,共6页
通过自制的中间体,在分子链上引入大位阻的侧基、聚碳酸酯和聚酯链段、磺酸盐链段、局部交联链段,制备了一种可用于单组分素色漆的阴离子型聚氨酯水分散体(PUD)。讨论了中间产物(二羟甲基叔碳酸酯)和IPDI的用量、聚碳酸酯二醇和磺酸盐... 通过自制的中间体,在分子链上引入大位阻的侧基、聚碳酸酯和聚酯链段、磺酸盐链段、局部交联链段,制备了一种可用于单组分素色漆的阴离子型聚氨酯水分散体(PUD)。讨论了中间产物(二羟甲基叔碳酸酯)和IPDI的用量、聚碳酸酯二醇和磺酸盐聚酯二醇的用量、交联单体类型、三羟甲基丙烷的用量对PUD性能和水性素色漆性能的影响。结果表明:制备的水性单组分素色漆达到汽车漆的使用要求。 展开更多
关键词 阴离子型 聚氨酯水分散体 水性素色漆
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油水比对阴离子型微乳液相行为的影响 预览
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作者 谷莹露 刘会娥 +2 位作者 陈爽 王龙 刘宇童 《化工学报》 EI CAS CSCD 北大核心 2019年第7期2626-2635,共10页
微乳液由水、油、盐、表面活性剂及助表面活性剂组成,其相行为及增溶情况受各组分的影响。研究发现,在SDBS(SDS、SLS)/航空煤油/水/正丁醇/氯化钠体系中,随着NaCl含量的不断增多,微乳液体系发生Winsor Ⅰ型→Winsor Ⅲ型→Winsor Ⅱ型... 微乳液由水、油、盐、表面活性剂及助表面活性剂组成,其相行为及增溶情况受各组分的影响。研究发现,在SDBS(SDS、SLS)/航空煤油/水/正丁醇/氯化钠体系中,随着NaCl含量的不断增多,微乳液体系发生Winsor Ⅰ型→Winsor Ⅲ型→Winsor Ⅱ型的相态转变。固定水的用量,通过油扫实验不断改变体系中的油水比,利用相图研究油水比对微乳液相行为的影响,并通过冷冻电镜对不同相态下微乳液的微观形貌进行了表征。随着油水比的增加,在低盐度下,体系由胶团溶液转变为Winsor Ⅰ型;而在高盐度下,体系发生由胶团溶液→Winsor Ⅱ型→Winsor Ⅲ型→Winsor Ⅰ型的相态转变。盐度一定时,微乳液的中相形成及消失所需的油量会随着表面活性剂浓度的增多而增多,且三种表面活性剂中,表面活性剂的增溶能力的大小顺序为SDBS>SDS>SLS,对煤油的敏感程度顺序为SLS>SDS>SDBS。 展开更多
关键词 油水比 微乳液 阴离子 相变 表面活性剂
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Anionic polymerization initiated by lithium amides for preparing high molecular weight polyacrylonitrile
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作者 Xiaolin Shi Jingyang Jiang 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第2期473-476,共4页
Lithium amides have been proved to be effective anionic initiators for the anionic polymerization of acrylonitrile to get high molecular weight polyacrylonitrile in this study. Polyacrylonitrile with weightaverage mol... Lithium amides have been proved to be effective anionic initiators for the anionic polymerization of acrylonitrile to get high molecular weight polyacrylonitrile in this study. Polyacrylonitrile with weightaverage molecular weight ranging from 1.02 × 10~6 g/mol to 1.23 ×10~6 g/mol (M_w/M_n= 1.9-2.2) could be prepared utilizing lithium amides derived from diisopropylamine, diethylamine, hexamethyldisilazane,dicyclohexylamine, and 2,2,6,6-tetramethylpiperidine as initiators. The polymerization of acrylonitrile proceeded in a homogeneous manner in N,N-di methyl for mamide and insignificant contribution of side reactions was confirmed. 展开更多
关键词 ANIONIC POLYMERIZATION ACRYLONITRILE High molecular weight polymer Lithium AMIDES POLYACRYLONITRILE
PREFACE
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《高分子科学:英文版》 SCIE CAS CSCD 2019年第9期I0010-I0011,共2页
Ionic polymerizations, including anionic and cationic polymerizations, constitute one of the most important sectors of chain growth polymerizations. The discovery of "living polymers" by Szwarc in anionic po... Ionic polymerizations, including anionic and cationic polymerizations, constitute one of the most important sectors of chain growth polymerizations. The discovery of "living polymers" by Szwarc in anionic polymerization ushered in an era of tailoring molecular structure of polymers. The idea of reversible deactivation of the propagating species in cationic polymerization in order to control the product molecular weight pioneered the research in controlled polymerization by using specific reversibly deactivating agent. Today, these methodologies are widely used not only for laboratory synthesis of polymers but also in rubber industry. 展开更多
关键词 IONIC POLYMERIZATIONS ANIONIC CATIONIC POLYMERIZATIONS
Synthesis of Alkyne-functionalized Polymers via Living Anionic Polymerization and Investigation of Features during the Post-“thiol-yne” Click Reaction
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作者 Lin-Can Yang Li Han +5 位作者 Hong-Wei Ma Pi-Bo Liu He-Yu Shen Chao Li Song-Bo Zhang Yang Li 《高分子科学:英文版》 SCIE CAS CSCD 2019年第9期841-850,共10页
"Thiol-yne" click reaction has already been widely applied in synthesis and modification of new polymer structures or novel materials due to its specific features. However, in most studies, only chain-end st... "Thiol-yne" click reaction has already been widely applied in synthesis and modification of new polymer structures or novel materials due to its specific features. However, in most studies, only chain-end strategy was employed when using the di-addition feature of thiol-yne reaction, thus the in-chain di-addition strategy could endow us with a broader space to develop the synthesis of advanced polymers. Therefore, in this paper, the features of in-chain mono and di-addition were investigated when modifying the alkynefunctionalized polymers to prepare grafted polymers via thiol-yne click reaction. The results showed that it is almost impossible to obtain the in-chain di-adducts even under excess feeding of chain-end thiol-functionalized grafts, while only the in-chain mono-adducts could be obtained efficiently. Further researches investigated that the controlled grafting could be encountered when carrying out the thiol-yne click reaction between chain-end alkyne-functionalized polystyrenes and chain-end thiol-functionalized polystyrenes under proper feedings. Therefore, the effect of steric?hindrance might be the primary reason for the alternative grafting via thiol-yne click reaction between in-chain and chain-end alkyne-functionalized polymers. 展开更多
关键词 Alkyne-functionalized polymers In-chain di-addition Thiol-yne CLICK reaction Living ANIONIC polymerization
Facile One-Pot Synthesis of ZSM-5 Aggregates with Interand Intra-Crystalline Mesopores for Methanol to Gasoline Conversion 预览
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作者 Yaquan Wang Chunyang Fan +3 位作者 Hongyao Li Fanjun Meng Chao Sun Liying Sun 《天津大学学报:英文版》 EI CAS 2019年第1期9-22,共14页
ZSM-5 aggregates consisting of superfine and hierarchical nanocrystals (combined with micropores and intra-crystalline mesopores) with an average size of 30nm were prepared through one-pot synthesis with the assistanc... ZSM-5 aggregates consisting of superfine and hierarchical nanocrystals (combined with micropores and intra-crystalline mesopores) with an average size of 30nm were prepared through one-pot synthesis with the assistance of anionic polyacrylamide (APAM). The resultant zeolites (AHN-ZSM-5) were characterized by XRD, ICP-OES, SEM, TEM, BET, NH 3 -TPD, Py-IR, and TG analyses and evaluated in the methanol to gasoline (MTG) reaction. Characterization results show that the hierarchical ZSM-5 aggregates possessed two kinds of mesopores, namely inter- and intra-crystalline mesopores. The amount of APAM considerably influenced the mesoporosity and textural properties of AHN-ZSM-5 zeolites. With the addition of APAM in the synthesis, the AHN-ZSM-5 zeolites exhibited large mesopore volume, large external surface area, and appropriate acidity. When applied in the MTG reaction, AHN-ZSM-5 demonstrated a catalytic lifetime that was 1.6 times longer than that of conventional ZSM-5 synthesized in the absence of APAM. 展开更多
关键词 Hierarchical nanocrystal Intra-crystalline MESOPORE ZSM-5 aggregate Anionic POLYACRYLAMIDE Methanol to gasoline
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Amphiphilic Dendrimer-like Copolymers with High Chain Density by Living Anionic Polymerization
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作者 Ke Zheng Jun-Po He 《高分子科学:英文版》 SCIE CAS CSCD 2019年第9期875-883,共9页
We report here a method for the preparation of amphiphilic dendrimer-like copolymers with dendritic polystyrene (PS) core and protonated poly(2-vinyl pyridine)(P2VP) or poly(methacrylic acid)(PMAA) shell. The method e... We report here a method for the preparation of amphiphilic dendrimer-like copolymers with dendritic polystyrene (PS) core and protonated poly(2-vinyl pyridine)(P2VP) or poly(methacrylic acid)(PMAA) shell. The method employed the efficient coupling reaction of anionic living polymer chains and chlorosilane. The synthesis started from a functionalized 3rd generation dendritic polystyrene, G3PS-g-SiCl, used as the precursor. The dendrimer-like copolymer of styrene and 2-vinyl pyridine, G3PS-g-P2VP, was synthesized by direct coupling of living P2VPLi to the precursor. The dendrimer-like copolymer of styrene and Zer/-butyl methacrylate, G3PS-g-PtBMA, was synthesized by an indirect procedure in which a living polymer containing mainly PtBMA segment was attached to the precursor. Both methods resulted in the formation of dendrimer-like copolymers with the high molecular weights (up to 8.5 × 10^6 Da), large molecular sizes (diameter up to 73 nm), and dense shells (number of arms up to 1300). These products, G3PS-g-P2VP and G3PS-g- PtBMA, were protonated with trifluoroacetic acid and acidic hydrolyzed, respectively. After transformation, amphiphilic dendrimer-like copolymers, G3PS-g-P2VPH^+ and G3PS-g-PMAA, were obtained. Preliminary results on the solution properties of the amphiphilic products were presented. 展开更多
关键词 Dendrimer-like polymer Living ANIONIC polymerization AMPHIPHILIC COPOLYMER
An anionic In(Ⅲ)-based metal-organic framework with Lewis basic sites for the selective adsorption and separation of organic cationic dyes
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作者 Qi Yang Bin Wang +2 位作者 Ya Chen Yabo Xie Jianrong Li 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第1期234-238,共5页
In this paper,a new anionic metal-organic framework,[In(PBPTTBA)][(CH3)2 NH2](BUT-29)has been synthesized through the reaction of tetratopic acid ligand with double Lewis pyridine sites,4,4’,4’’,4’’’-(4,4’-(1,4... In this paper,a new anionic metal-organic framework,[In(PBPTTBA)][(CH3)2 NH2](BUT-29)has been synthesized through the reaction of tetratopic acid ligand with double Lewis pyridine sites,4,4’,4’’,4’’’-(4,4’-(1,4-phenylene)bis(pyridine-6,4,2-triyl))tetrabenzoic acid(H4 PBPTTBA)and In(NO3)2·5H2O and fully characterized by single-crystal X-ray diffraction(SXRD),powder X-ray diffraction(PXRD),thermogravimetric analysis(TGA),infrared spectroscopy(IR),and elemental analysis(EA).BUT-29 can be used as an efficient adsorbent for the selective removal of organic cationic dyes in N,N0-dimethylformamide(DMF)solution.The adsorption capacities of BUT-29 toward methylene blue and crystal violet at 298 K can reach 1119 mg/g and 832 mg/g,respectively.Moreover,the adsorbed dyes can be released in the DMF solution of LiNO3 gradually. 展开更多
关键词 ANIONIC METAL-ORGANIC framework LEWIS basic sites Selective adsorption SEPARATION ORGANIC DYE
Polymerization Mechanism of Methyl Methacrylate Initiated by Ethyl Acetate/t-BuP4
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作者 De-Yong Xia Qi-Min Jiang +4 位作者 Wen-Yan Huang Hong-Jun Yang Xiao-Qiang Xue Li Jiang Bi-Biao Jiang 《高分子科学:英文版》 SCIE CAS CSCD 2019年第6期598-603,共6页
The anionic polymerization of methyl methacrylate(MMA) was carried out using phosphazene base t-BuP4 and ethyl acetate(EA) as the catalyst and the initiator, respectively. Gas chromatography(GC), size exclusion chroma... The anionic polymerization of methyl methacrylate(MMA) was carried out using phosphazene base t-BuP4 and ethyl acetate(EA) as the catalyst and the initiator, respectively. Gas chromatography(GC), size exclusion chromatography(SEC) measurements, and nuclear magnetic resonance(NMR) analyses were used to reveal the polymerization mechanism and to confirm the polymer structure. The results confirmed the proposed polymerization mechanism and the polymer structure, while the initiator efficiency was low. Meanwhile,the initiation by methoxy anion coming from hydrolysis of the ester bond in MMA was also observed. As a result, there is a marked deviation between the theoretical molecular weight and the measured molecular weight, and it is essential to carry out the polymerization at excessive dosage of t-BuP4 for preparing polymers with narrow molecular weight distribution. 展开更多
关键词 PHOSPHAZENE base (/-B11P4) Methyl METHACRYLATE ETHYL ACETATE ANIONIC polymerization
Synthesis, Structure and Biological Activities of a Novel Anionic Organotin (IV) Complex {[(p-ClC6H4CH2)Sn(H2O)(Cl)2OCOCH(O)CH(O) CO2Sn(H2O)(Cl)2(p-ClC6H4CH2)]?2(HNEt3)} 预览
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作者 HE Tang-Feng ZHANG Fu-Xing +6 位作者 YAO Shu-Fen ZHU Xiao-Ming SHENG Liang-Bing KUANG Dai-Zhi FENG Yong-Lan YU Jiang-Xi JIANG Wu-Jiu 《结构化学》 SCIE CAS CSCD 2018年第12期1899-1906,1844共9页
A novel anionic organotin(IV) complex {[(p-ClC6H4CH2)Sn(H2O)(Cl)2OCO-CH(O)CH(O)CO2Sn(H2O)(Cl)2(p-ClC6H4CH2)]?2(HNEt3)}(1) was synthesized by the reaction of di(p-chlorobenzy)tin dichloride with the D-tartaric acid in ... A novel anionic organotin(IV) complex {[(p-ClC6H4CH2)Sn(H2O)(Cl)2OCO-CH(O)CH(O)CO2Sn(H2O)(Cl)2(p-ClC6H4CH2)]?2(HNEt3)}(1) was synthesized by the reaction of di(p-chlorobenzy)tin dichloride with the D-tartaric acid in 2:1 molar in the presence of an organic base triethylamine.The structure was characterized by elemental analysis,IR,TG,XRD and single-crystal X-ray diffraction.It crystallizes in triclinic,P space group,with a=0.7067(1),b=1.9762(3),c=2.2383(3) nm,α=91.544(2)°,β=90.075(2)°,γ=90.110(2)°,V=3.1247(7) nm^3,Z=3,Dc=1.621 g/cm^3,μ(MoKα)=16.29 cm^-1,F(000)=1530,R=0.0394,wR=0.1092,(Δρ)max=1224 and (Δρ)min=–840 e/nm^3.The stabilities,orbital energies and composition characteristics of some frontier molecular orbitals of 1 have been carefully investigated with quantum chemistry calculation.In addition,the in vitro antitumor activity suggested that 1 had stronger inhibitory activity on H460,MCF7 than on A549. 展开更多
关键词 ANIONIC organotin(IV) COMPLEX D-tartaric acid synthesis structure vitro anticancer activity
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异氰酸酯指数对阴离子型水性聚氨酯性能的影响 预览 被引量:1
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作者 魏欣 隋泽华 +2 位作者 刘洋子建 张均 姜志国 《聚氨酯工业》 北大核心 2018年第2期40-42,共3页
以二羟曱基丁酸(DMBA)和聚乙二醇(PEG)为亲水扩链剂,甲苯二异氰酸酯(TDI)为异氰酸酯组分,聚氧化丙烯二醇(PPG)为低聚物多元醇组分,采用预聚体法合成了一系列阴/非离子型水性聚氨酯(WPU)。通过万能材料试验机、粒後测试、接触角测定等表... 以二羟曱基丁酸(DMBA)和聚乙二醇(PEG)为亲水扩链剂,甲苯二异氰酸酯(TDI)为异氰酸酯组分,聚氧化丙烯二醇(PPG)为低聚物多元醇组分,采用预聚体法合成了一系列阴/非离子型水性聚氨酯(WPU)。通过万能材料试验机、粒後测试、接触角测定等表征手段研究了异氰酸酯指数(R值)对水性聚氨酯乳液及胶膜性能的影响。结果表明,随着异氰酸酯指数的增加,乳液粒径逐渐增加,Zeta电位绝对值逐渐减小;肢膜的拉伸强度逐渐增加,断裂伸长率逐渐减小,表面接触角逐渐增大。 展开更多
关键词 异氰酸酯指数 水性聚氨酯 阴离子型
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乙二醇基Gemini表面活性剂的合成研究进展 预览
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作者 葛秀娟 高文超 +3 位作者 黄双平 李兴 魏文珑 常宏宏 《日用化学工业》 CSCD 北大核心 2018年第11期647-655,共9页
综述了以乙二醇为原料制备阳离子、阴离子、非离子和两性离子Gemini表面活性剂的合成方法,并对合成路线进行了总结和分析,对产物的性能及其应用进行了阐述。以乙二醇为主要原料合成的Gemini表面活性剂具有更高的表面活性、较低的临界胶... 综述了以乙二醇为原料制备阳离子、阴离子、非离子和两性离子Gemini表面活性剂的合成方法,并对合成路线进行了总结和分析,对产物的性能及其应用进行了阐述。以乙二醇为主要原料合成的Gemini表面活性剂具有更高的表面活性、较低的临界胶束浓度、良好的润湿性和抗菌性,应用范围较广。 展开更多
关键词 乙二醇 GEMINI表面活性剂 阳离子 阴离子 非离子 两性离子
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聚氨酯改性有机硅阴离子乳液的合成及应用 预览
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作者 何杰芳 陈焜 周向东 《印染助剂》 北大核心 2018年第7期27-30,共4页
以十二烷基苯磺酸为阴离子乳化剂和催化剂,脂肪醇聚氧乙烯醚AEO9为非离子乳化剂,将含氨烃基偶联剂与有机硅单体进行乳液共聚,再加入聚氨酯预聚体进行改性,得到阴离子型聚氨酯改性有机硅乳液。通过红外光谱表征了产物结构,探讨了n(NCO)... 以十二烷基苯磺酸为阴离子乳化剂和催化剂,脂肪醇聚氧乙烯醚AEO9为非离子乳化剂,将含氨烃基偶联剂与有机硅单体进行乳液共聚,再加入聚氨酯预聚体进行改性,得到阴离子型聚氨酯改性有机硅乳液。通过红外光谱表征了产物结构,探讨了n(NCO)∶n(OH)、PPG分子质量、偶联剂KH550用量以及预聚体用量对产物性能的影响,优化工艺为:n(NCO)∶n(OH)=2.0∶1,PPG分子质量1 000,KH550用量3.5%(对D4质量),预聚体用量5%(对有机硅乳液总质量)。将该嵌段硅油应用在T/R混纺织物上,结果表明:聚氨酯改性后的有机硅阴离子乳液具有一定的防水性和优异的回弹性。 展开更多
关键词 聚氨酯 阴离子 有机硅
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羧酸盐型双子表面活性剂的合成及应用研究进展 预览
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作者 郭乃妮 郑敏燕 《石油化工》 CSCD 北大核心 2018年第11期1276-1281,共6页
双子表面活性剂又称Gemini表面活性剂,具有在气/液表面吸附和降低表面张力的性能良好、复配协同效应强、Krafft点低、易聚集生成胶团、润湿性和钙皂分散能力良好、易生物降解等独特优势,在能源、医药、农业、精细化工等领域具有广泛的... 双子表面活性剂又称Gemini表面活性剂,具有在气/液表面吸附和降低表面张力的性能良好、复配协同效应强、Krafft点低、易聚集生成胶团、润湿性和钙皂分散能力良好、易生物降解等独特优势,在能源、医药、农业、精细化工等领域具有广泛的用途。介绍了羧酸盐型阴离子双子表面活性剂的分类及合成方法,分析了羧酸盐型阴离子双子表面活性剂在纺织及皮革工业、日用化工、三次采油、煤炭工业、金属防护、有机农药和新材料的制备等领域的应用概况,并对新型双子表面活性剂的合成方向和发展前景进行了展望。 展开更多
关键词 羧酸盐 阴离子 GEMINI表面活性剂 合成
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阴离子Gemini表面活性剂的合成研究进展 预览
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作者 郭乃妮 刘聪 杨静 《皮革与化工》 CAS 2018年第4期14-18,共5页
阴离子Gemini表面活性剂具有优良的乳化性、发泡性、去污能力、耐盐性、分散性、易生物降解性,在日用化工、三次采油、金属防护、环境保护、新型材料等领域具有广泛的用途。研究综述了磺酸盐型和羧酸盐型Gemini表面活性剂的分类、合成... 阴离子Gemini表面活性剂具有优良的乳化性、发泡性、去污能力、耐盐性、分散性、易生物降解性,在日用化工、三次采油、金属防护、环境保护、新型材料等领域具有广泛的用途。研究综述了磺酸盐型和羧酸盐型Gemini表面活性剂的分类、合成及应用,展望了新型阴离子Gemini表面活性剂的发展前景。 展开更多
关键词 阴离子 GEMINI 表面活性剂 合成
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Cellulose Acetate Film and Layered Double Hydroxide as Determination Method of Available Phosphorus in the Soil 预览
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作者 Gustavo Franco de Castro Jader Alves Ferreira +4 位作者 Allan Robledo Fialho e Moraes Reinaldo Bertola Cantarutti Frederico Garcia Pinto Jairo Tronto Roberto Ferreira Novais 《农业科学与技术:B》 2018年第7期420-432,共13页
The determination of available phosphorus(P)in soil is essential to the evaluation of the current fertility status,and therefore,for recommending the required phosphate fertilizers for the cultivation of crops.The mos... The determination of available phosphorus(P)in soil is essential to the evaluation of the current fertility status,and therefore,for recommending the required phosphate fertilizers for the cultivation of crops.The mostly used extractants around the country are Mehlich-1(M-1)and anionic resins(AR)and mixed resins(MR).However,there are still controversies in relation to the method that should be used,due to of particularities of each extractor.Therefore,the main objectives of this work was to assess the applicability of films of binary combination between cellulose acetate(CA)biopolymer and calcinated layered double hydroxide(LDH-c),named CAF-LDH-c,as a new extractor of available P in soils.For this,two experiments were set out.In the first one,sub-samples of an Oxisol layer 0-20 cm were used and submitted to increasing doses of total P(0,250,750 and 2,250 mg/dm3)in the form of monoammonium phosphate(MAP)at different incubation time(5,30,60 and 90 d).In the second experiment,samples of 20 soils from different origins and contents of available P were used with distinct chemical and physical attributes.The analysis of available P by M-1,AR,MR,Mehlich-3(M-3)and CAF-LDH-c extractants was done in both experiments.The efficiency of the extractants was evaluated by Pearson’s linear correlation.The correlation between values of P extracted from soil in the first experiment was highly significant among all extraction methods used,including for CAF-LDH-c.In the second experiment,CAF-LDH-c showed significant correlation(p<0.01)with M-1,M-3,AR and MR.Thus,the significant correlations of the extractant being tested(CAF-LDH-c)with those usually used indicates the possibility of this new method of routine laboratories for assessing the P availability of for the cultivation of crops. 展开更多
关键词 Available P Mehlich-1 Mehlich-3 ANIONIC RESIN MIXED RESIN
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KH550改性阴离子型聚丙烯酰胺的应用 预览
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作者 闫君芝 刘英 《当代化工》 CAS 2018年第5期890-892,896共4页
以丙烯酰胺(AM)、甲基丙烯酰氧乙基三甲基氯化铵(DMC)、乙二胺四乙酸二钠、四甲基乙二胺(TMEDA)、偶氮二异丁氰(AIBA)、单体丙烯酸(AA)和3-氨丙基三乙氧基硅烷(KH550)等作为主要试剂,利用水分散聚合技术制备KH550改性的阴... 以丙烯酰胺(AM)、甲基丙烯酰氧乙基三甲基氯化铵(DMC)、乙二胺四乙酸二钠、四甲基乙二胺(TMEDA)、偶氮二异丁氰(AIBA)、单体丙烯酸(AA)和3-氨丙基三乙氧基硅烷(KH550)等作为主要试剂,利用水分散聚合技术制备KH550改性的阴离子型聚丙烯酰胺水分散体系,确定其稳定性后进行红外表征。并进行应用研究,得出最佳絮凝效果时各试剂的用量。 展开更多
关键词 丙烯酰胺 阴离子 水处理
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溶剂在反应控制相转移催化反应中的影响
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作者 张金帅 于凤丽 +2 位作者 袁冰 解从霞 于世涛 《化学进展》 CSCD 北大核心 2018年第2期304-313,共10页
本文主要探讨了溶剂在反应控制相转移催化反应中的影响。反应控制相转移催化体系兼具均相催化与多相催化的优点,既解决了均相催化中催化剂难以回收的问题又克服了多相催化中反应速率慢、反应时间较长、活性组分易流失以及选择性较低的... 本文主要探讨了溶剂在反应控制相转移催化反应中的影响。反应控制相转移催化体系兼具均相催化与多相催化的优点,既解决了均相催化中催化剂难以回收的问题又克服了多相催化中反应速率慢、反应时间较长、活性组分易流失以及选择性较低的缺点。催化剂在反应体系中所表现出来的反应控制相转移特性不仅和本身的阴离子、阳离子组成有关,还和体系中溶剂的种类密切相关。合适的溶剂不但可以提高底物的转化率以及产物的产率,同时还有利于催化剂的回收。本文就溶剂在多种反应控制相转移催化体系中的影响进行了综述,包括烯烃环氧化、醇氧化制备醛/酮、酯化、烯/醇氧化制备二元羧酸、缩醛反应、氧化脱硫、羟基化反应以及Se催化还原等体系。最后,对目前催化体系中存在的问题提出了可能的解决方案并对反应控制相转移催化体系在其他方面的潜在应用和发展进行了展望。 展开更多
关键词 反应控制相转移催化 溶剂 阴离子 阳离子 催化剂回收
P2-type Na0.6[Mg(Ⅱ)0.3Mn(Ⅳ)0.7]O2 as a new model material for anionic redox reaction
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作者 Xiaohui Rong Fei Gao +2 位作者 Yaxiang Lu Kai Yang Yongsheng Hu 《中国化学快报:英文版》 SCIE CAS CSCD 2018年第12期1791-1794,共4页
A new model material of Na0.6[Mg(Ⅱ)0.3Mn(Ⅳ)0.7]O2, with only Mg2+ and Mn4+ in the transition metal layers, is synthesized for the research of anionic redox reaction. The material delivers a capacity of ~130 mAh/g wi... A new model material of Na0.6[Mg(Ⅱ)0.3Mn(Ⅳ)0.7]O2, with only Mg2+ and Mn4+ in the transition metal layers, is synthesized for the research of anionic redox reaction. The material delivers a capacity of ~130 mAh/g with a long plateau at ~4.2 V in the initial charge profile, indicating anionic redox reaction(ARR) involved during the initial desodiation process. In the following cycles, the reversible capacity can reach a high value of ~210 mAh/g, which is probably derived from the participation of both ARR and Mn3+/Mn4+ redox couples, further proving the charge compensation from ARR during the initial charge and following cycles. The designed cathode material without Mn3+ helps avoid the influence of oxygen activity from transition metals, enabling the investigation of ARR without other distractions. 展开更多
关键词 Na-ion batteries LAYERED oxide CATHODE ANIONIC redox reaction Na0.6[Mg0.3Mn0.7]O2
阴离子型油溶性稠油降黏剂的合成及评价 预览 被引量:2
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作者 陈陆建 杨兆中 《应用化工》 CAS CSCD 北大核心 2016年第2期312-315,323共5页
针对油溶性稠油降黏剂存在的选择性强和降黏效果差等问题,通过乳液聚合方式合成了一种阴离子型的多元共聚物油溶性稠油降黏剂,最佳合成条件为:在氮气的保护下,n(2-丙烯酰胺基-2-甲基丙磺酸)∶n(甲基丙烯酸长链酯)∶n(苯乙烯)∶n... 针对油溶性稠油降黏剂存在的选择性强和降黏效果差等问题,通过乳液聚合方式合成了一种阴离子型的多元共聚物油溶性稠油降黏剂,最佳合成条件为:在氮气的保护下,n(2-丙烯酰胺基-2-甲基丙磺酸)∶n(甲基丙烯酸长链酯)∶n(苯乙烯)∶n(丙烯酸)=1∶10∶6∶5,引发剂加量0.5%,反应时间6 h,反应温度70℃,单体浓度25%。该降黏剂对多种稠油都具有一定降黏效果,尤其对含水率高的稠油效果更好;在50℃条件下,降黏剂加量950 mg/L时,降黏率可达59.29%。考察了稠油中胶质、沥青质加降黏剂前后的红外光谱,分析了其降黏机理:降黏剂加入后,降黏剂分子与稠油中的胶质、沥青质发生作用,消弱了胶质沥青质聚集体间的氢键结合能力,改变了原有聚集体的空间网状结构,从而降低稠油黏度。 展开更多
关键词 稠油 稠油降黏剂 阴离子型 聚合物 红外光谱
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