首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 133 毫秒
1.
以氯甲基辛醚为氯甲基化试剂, 对杂萘联苯聚芳醚酮酮(PPEKK)进行改性, 制备了氯甲基化杂萘联苯聚芳醚酮酮(CMPPEKK). 考察了氯甲基辛醚用量对氯甲基化程度的影响. 1H NMR表明氯甲基成功引入到聚合物结构中. 采用溶液法制备了CMPPEKK基膜, 然后将其进行三甲胺胺化, 制备了季铵化杂萘联苯聚芳醚酮酮(QAPPEKK)阴离子交换膜. 表征了QAPPEKK的基本性能: 离子交换容量, 含水率, 面电阻. QAPPEKK膜的含水率随离子交换容量增加而升高, 面电阻随离子交换容量的增加而降低. 将QAPPEKK膜应用于全钒液流电池(VRB)中, 电池的能量效率达到85.0%, 电流效率为98.5%, 电压效率为86.3%.  相似文献   

2.
超支化聚芳醚酮(HBPEKs)由于具有独特的理化特性和潜在的应用价值近年来备受关注.本文综述了HBPEKs最新的研究进展.HBPEKs可以由单单体和双单体方法来制备,文中重点介绍了HBPEKs的一些经典合成方法;同时,对HBPEKs的结构性能、表征手段和应用等进行了详细的描述;最后,指出了HBPEKs研究过程中需要解决的问题.  相似文献   

3.
本文通过研究含氯侧基液晶聚芳醚酮/含甲基苯侧基聚芳醚酮共混体系(结晶/非晶)环带球晶的形态演变和发展过程; 利用选择性溶剂刻蚀方法确定共混体系环带球晶的相组成和相结构, 探讨了环带球晶的形成机理.  相似文献   

4.
利用双酚A型聚芳醚酮与联硼酸频哪醇酯在[Ir(COD)Cl]2和4,4'-二叔丁基-2,2'-联吡啶催化下反应,制备了新型含硼酸酯双酚A型聚芳醚酮,通过控制联硼酸频哪醇酯的投入量来实现硼酸酯的定量引入.再经过高碘酸钠作用得到含硼酸双酚A型聚芳醚酮,最后,通过高效Suzuki-Miyaura反应将偶氮定量引入到聚芳醚酮主链.利用核磁共振(1H NMR)确定了聚合物的结构,利用凝胶渗透色谱(GPC)确定了聚合物的分子量,利用差示扫描量热分析(DSC)和热失重分析(TGA)研究了聚合物的热性能,利用紫外-可见光谱(UVVis)研究了偶氮聚芳醚酮的光谱学性能.  相似文献   

5.
含不同取代基的Cardo聚芳醚酮──合成与表征   总被引:3,自引:0,他引:3  
含不同取代基的Cardo聚芳醚酮──合成与表征王忠刚,陈天禄,徐纪平(中国科学院长春应用化学研究所长春130022)关键词Cardo聚芳醚酮,合成与表征,自由体积,玻璃化转变温度酚酞型Cardo聚芳醚酮(PEK-C)是长春应化所合成的一种新型高一T,...  相似文献   

6.
首先合成氨基封端的超支化聚芳醚酮(NH_2-HPAEK),然后以NH_2-HPAEK四氢呋喃溶液和聚乙烯醇(PVA)水溶液分别作为分散相和连续相,借助溶剂挥发法制备以NH_2-HPAEK为核、PVA为壳的空心多孔微球;通过氨基与乙二醛的交联反应,实现空心多孔微球结构的稳定化,进而满足其在一些特定环境下的使用要求.  相似文献   

7.
PPEKK/PEI共混物的相容性及拉伸性能   总被引:3,自引:0,他引:3  
作为相容体系 ,聚芳醚酮与聚醚酰亚胺 (PEI)共混物体系的研究受到了研究者的重视[1~ 4] .由于现在已商品化的聚芳醚酮基本上都是半结晶型聚合物 ,所以有有关无定型聚芳醚酮与聚醚酰亚胺共混物的研究鲜见报道 .含二氮杂萘酮结构聚芳醚酮酮 (PPEKK)是一种新型耐高温聚合物 ,相比于已经商品化的各种聚芳醚酮 ,PPEKK除具有优异的综合性能外 ,它最大的特点表现在以下两方面 ,PPEKK耐热性突出 ,玻璃化转变温度 (Tg)为 2 4 5℃左右 ,远高于各种商品化的聚芳醚酮 ;PPEKK为无定型聚合物 ,易溶于多种有机极性溶剂 ,大大的扩…  相似文献   

8.
通过傅克酰基化反应合成4,4'-二(4-氟苯甲酰基)二苯醚、4,4'-二(五氟苯甲酰基)二苯醚、4,4'-二(4-氟苯甲酰基)二苯硫醚以及4,4'-二(五氟苯甲酰基)二苯醚4种长链双卤单体,并进一步制备了含二氮杂萘酮聚芳醚酮聚合物.通过多氟取代双卤单体在含二氮杂萘酮聚芳醚酮聚合物主链中引入氟原子.多氟取代双卤单体具有多...  相似文献   

9.
通过加入第三单体4,4'-二(2-甲基苯氧基)二苯砜与1,4-二苯氧基苯(DPB)和对苯二甲酰氯(TPC)进行三元无规共聚,合成了一系列分子主链带砜基和主链芳环上含甲基侧基的聚(芳醚砜醚酮酮-co-醚醚酮酮)共聚物,并用FT-IR、DSC、WAXD和TG对其进行了表征.结果表明,共聚物的玻璃化转变温度随着第三单体摩尔含量的增加而逐渐升高,熔融温度则逐渐降低,当其摩尔含量为10%~30%时,共聚物具有优良的耐热性能及耐溶剂、耐酸碱性能.  相似文献   

10.
低温溶液缩聚合成聚芳醚酮酮的研究   总被引:42,自引:3,他引:42  
低温溶液缩聚合成聚芳醚酮酮的研究宋才生,蔡明中,周丽云(江西师范大学化学系南昌330027)关键词低温溶液缩聚,付一克或化反应,聚芳醚酮酮,二苯醚聚芳醚酮酮(PEKK)是一种新型的热塑性耐热高分子材料,具有优异的机械力学性能,耐溶剂抗化学腐蚀性能,抗...  相似文献   

11.
Trans-1,2-bis(2'-(5 '-phenyl-1 ',3',4'-oxadiazolyl)) cyclopropane (BDCP) and its eleven substituted novel derivatives were synthesized. Besides four derivatives of l,2-bis(2'-(5'-phenyl-l ' , 3 ' , 4 ' -ox-adiazo1yl))ethane (BPDS) were also synthesized as model compounds. The crystal structure of ethyl BDCP was determined and the cyclopropane ring was found to be able to transmit conjugation between the aromatic groups directly bonding with it by studying the ultraviolet and fluorescent spectra of the above compounds.  相似文献   

12.
5-氟脲嘧啶的β-D-半乳吡喃糖苷的合成   总被引:7,自引:0,他引:7  
5-氟脲嘧及其衍生物是目前临床上广泛使用的抗代谢类抗癌药物, 主要适用于消化道癌、乳腺癌、肺癌等, 但具有一定的毒性, 主要表现为骨髓抑制和胃肠道反应。我们以Koenigs-Knorr法和相转催化法合成了5-氟脲嘧啶的两种类型(-N型, -O型)的半乳吡喃糖苷。这些糖苷类化合物在体内糖苷的作用下, 有可能缓慢地分解释放出5-氟脲嘧啶, 降低其毒性, 提高抑瘤效果。  相似文献   

13.
The palladium-catalyzed coupling reaction of 6-iodoisoflavone, prepared from 3'-iodoacetophenone derivative, with 2-methyl-3-butyn-2-ol gave 6-alkynylisoflavone derivative, which was hydrogenated to give 6-alkylhydroxyisoflavone (luteone hydrate) (2). Dehydration of 2 gave 2',4',5,7-tetrahydroxy-6-prenylisoflavone (luteone) (1). Wighteone hydrate (3) was also synthesized from 6-iodotris(benzyloxy)isoflavone in a similar manner. 6-Alkyl-4'5,7-trihydroxy-coumaronochromone (4) was synthesized by oxidative cyclization of 2 with o-chloranil.  相似文献   

14.
The novel bridged nucleic-acid analogue 2',4'-BNA(NC) (2'-O,4'-C-aminomethylene bridged nucleic acid), containing a six-membered bridged structure with an N-O linkage, was designed and synthesized efficiently, demonstrating a one-pot intramolecular NC bond-forming key reaction to construct a perhydro-1,2-oxazine ring (11 and 12). Three monomers of 2',4'-BNA(NC) (2',4'-BNA(NC)[NH], [NMe], and [NBn]) were synthesized and incorporated into oligonucleotides, and their properties were investigated and compared with those of 2',4'-BNA (LNA)-modified oligonucleotides. Compared to 2',4'-BNA (LNA)-modified oligonucleotides, 2',4'-BNA(NC) congeners were found to possess: (i) equal or higher binding affinity against an RNA complement with excellent single-mismatch discriminating power, (ii) much better RNA selective binding, (iii) stronger and more sequence selective triplex-forming characters, and (iv) immensely higher nuclease resistance, even higher than the S(p)-phosphorthioate analogue. 2',4'-BNA(NC)-modified oligonucleotides with these excellent profiles show great promise for applications in antisense and antigene technologies.  相似文献   

15.
Stereoselective synthesis of novel 2',3'-didehydro-2',3'-dideoxy-4'-selenonucleosides (4'-seleno-d4Ns) 4a- c was accomplished via 4'-selenoribofuranosyl pyrimidines 11a- c, as key intermediates. 4'-Selenoribofuranosyl pyrimidines 11a- c were efficiently synthesized from d-ribose or d-gulonic gamma-lactone using a Pummerer-type condensation as a key step. Introduction of 2',3'-double bond was achieved by treating cyclic 2',3'-thiocarbonate with 1,3-dimethyl-2-phenyl-1,3,2-diazaphospholidine.  相似文献   

16.
2,6-二甲基-3,5-二氯-4-吡啶酚糖苷的合成   总被引:4,自引:0,他引:4  
在相转移催化条件下, 使 a-D-乙酰基化溴代的葡萄糖、半乳糖、葡萄糖醛酸甲酯1a, 1b, 1c分别与2,6-二甲基-3,5-二氯-4-吡啶酚(俗称氯吡醇, 氯羟吡啶)作用, 合成了氯吡醇的糖苷: 1-O-(2',6'-二甲基-3',5'-二氯-4'-吡啶基)-2,3,4,6-四-O-乙酰基-β-D-葡萄吡喃糖苷(2a), 1-O-(2',6'-二甲基-3',5'-二氯-4'-吡啶基)-2,3,4,6-四-O-乙酰基β-D-半乳吡喃糖苷(2b), 1-O-(2'6'-二甲基-3',5'-二氯-4'-吡啶基)-2,3,4-三-O-乙酰基-β-D-葡萄吡喃糖醛酸甲酯(2c)。2a, 2b, 2c分别在甲醇中氨解, 相应得到: 1-O-(2', 6'-二甲基-3',5'-二氯-4'-吡啶基)-β-D-葡萄吡喃糖苷(3a), 1-O(2',6'-二甲基-3',5'-二氯-4'-吡啶基)-β-D-半乳吡喃糖苷(3b),1-O-(2', 6'-二甲基-3',5'-二氯-(4'-吡啶基)-β-D-葡萄吡喃糖醛酸酰胺(3c)。2c用CH~3ONa/CH~3OH处理, 得到1-O-(2',6'-二甲基-3',5'-二氯-4'-吡啶基)-β-D-葡萄吡喃糖醛酸甲酯(3d)。  相似文献   

17.
分别以Fe(Cl O4)3、FeCl3、Fe2(SO4)3作为氧化剂,对3′,4′-乙撑二氧-2,2′∶5′,2″-三噻吩(TET)进行了化学氧化聚合,并研究了聚合条件对聚合物结构和电化学性能的影响。利用红外光谱、紫外光谱、X射线衍射对聚合物进行了表征,采用循环伏安、恒电流充放电等电化学方法研究了聚合物的电化学性能。结果表明:当TET与Fe(Cl O4)3的摩尔比为1∶4,反应温度为18℃,反应时间为12 h时,聚3′,4′-乙撑二氧-2,2′∶5′,2″-三噻吩(PTET)具有更好的共轭结构和电化学性能,导电率可达1.47 S/m,比电容可达133 F/g。  相似文献   

18.
[structure: see text]. A stereselective synthesis of 3-oxabicyclo[3.2.0]heptane nucleoside analogues, which were designed as conformational mimics of the anti-HIV agents 2',3'-didehydro-2',3'-dideoxythimidine (stavudine, d4T) and 2',3'-didehydro-2',3'-dideoxyadenosine (d4A), is described. The target compounds were prepared by condensation of a common intermediate bicyclic acetate, derived from a homochiral 2(5H)-furanone, with pyrimidine and purine bases under modified Vorbrüggen conditions. The conformational behavior of the synthesized nucleoside analogues was studied by NMR spectroscopy and X-ray crystallography.  相似文献   

19.
A series of terphenyl-edged Fe(4)L(6) cages were synthesized from substituted 4,4'-diamino-p-terphenyls, 2-formylpyridine, and iron(II). For the parent diaminoterphenyl, all three possible diastereomers, with T, S(4), and C(3) point symmetries, were formed in nearly equal amounts, as determined by (1)H and (13)C NMR. When 2,2″-dimethylterphenylenediamine was used, the T-symmetry diastereomer was observed to predominate. The use of 2',3',5',6'-tetramethylterphenylenediamine generated predominantly the S(4) cage diastereomer, whereas 2',5'-dimethylterphenylenediamine produced the C(3)-symmetric cage to a greater degree than the other two diastereomers. The factors contributing to the transfer of chiral information between metal vertices were analyzed, and the general principles underlying the delicately balanced thermodynamics were determined.  相似文献   

20.
A convenient approach for the preparation of(1S,3’R.4’S,5’S,6’R)-5-chloro-6-[(4-ethylphenyl)methyl]- 3’,4’,5’,6’-tetrahydro-6’-(hydroxymethyl)-spiro[isobenzofuran-1(3H),2’-[2H]pyran]-3’,4’,5’-triol is developed. The targeted compound was synthesized from 2-bromo-4-methylbenzoic acid in nine steps and the isomers of undesired ortho-products were avoided during the preparation.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号