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1.
N-[4-(磺酰胺)苯基]丙烯酰胺(ASPAA)单体可以均聚或与其它单体共聚合成具有药理活性的聚合物,制成水溶性、毒副作用小、具有缓释作用的大分子药物.同时,由于磺酰胺基具有一定的碱溶性,ASPAA与丙烯酸酯类等单体的共聚物可用于制备可碱显影、显影宽容度和耐印力等性能良好的平印、计算机直接制版版材.有关ASPAA与其它单体共聚的竞聚率还鲜见报道.本文在合成ASPAA单体的基础上,对ASPAA/丙烯腈和ASPAA/甲基丙烯酸甲酯共聚的竞聚率进行了研究。  相似文献   

2.
研究了金鸡纳碱与丙烯酰胺的自由基共聚反应。发现在氯仿/乙醇混合溶剂中采用硫酸奎宁作为金鸡纳碱共聚单体可以合成收率和金鸡纳碱含量均较高的新型水溶性共聚物。对共聚物用元素分析、核磁共振、粘度和旋光度测定等方法进行表征,发现在假定丙烯酰胺链节为非光活性的条件下共聚物中金鸡纳碱链节的比旋光度随聚合配方中金鸡纳碱含量的增加而增加。  相似文献   

3.
水溶性偶氮引发体系引发DMDAAC-AM共聚合   总被引:4,自引:0,他引:4  
水溶性偶氮引发体系引发DMDAAC-AM共聚合;二甲基二烯丙基氯化铵; 丙烯酰胺; 共聚; AIBA·2HCl-NaHSO3引发剂  相似文献   

4.
娄清香  杜代军  关丹  阙庭 《合成化学》2018,26(10):770-775
采用氧化还原胶束聚合法,将改性β-环糊精、N-苯乙基甲基丙烯酰胺、丙烯酰胺和丙烯酸等水溶性单体进行共聚,合成了超分子聚合物(HMPAM),其结构和性能经SEM, FT-IR和流变仪表征。结果表明:HMPAM为典型的幂律型流体,具有良好的增稠性能和抗剪切性能。  相似文献   

5.
采用自由基水溶液共聚法制备了带有负电荷的水溶性聚丙烯酰胺,研究了水溶液中聚合物与阳离子表面活性剂的相互作用及所导致的水溶性、黏度和流变学性质的变化,为进一步研究驱油提供了理论基础.  相似文献   

6.
<正> 我们已经报道过甲基丙烯酸甲酯与N-对卤苯基甲基丙烯酰胺共聚合的研究。本文工作合成了丙烯酸甲酯与N-对卤苯基甲基丙烯酰胺共聚体,研究了这二组共聚体系的聚合反应、共聚体的组成、估算了单体的竞聚率,比较了这两种酰胺对丙烯酸甲酯与甲基丙烯酸甲酯的反应活性。  相似文献   

7.
不久前我们曾报导了聚丙烯酰胺的水溶液在室温或55℃时有可能与过氧化氢发生均相氧化反应,形成聚丙烯酰胺大分子过氧化物.这种水溶性的聚丙烯酰胺大分子过氧化物可引发烯类单体的接枝共聚,得到相应的碳链接枝共聚物。利用这种简便的接枝方法不仅可以合成一系列具有综合性能的接枝共聚物新品种,而且对大分子过氧化物引发烯类单体接枝共聚反应历程的研究也具有一定意义。  相似文献   

8.
研究了金鸡纳碱与丙烯酰胺的自由基共聚反应。发现在氯仿/乙醇混合溶剂中采用硫酸奎宁作为金鸡碱共聚单体可以合成收率和金鸡纳碱含量的较高的新型水溶性共聚物。对共聚物用元素分析;、核磁共振、粘度和旋光度测定等方法进行表征,发现在假定丙烯酰胺链节为非光生的条件下共聚物中金鸡纳碱锭节的比旋光度随聚合配方中金鸡纳碱含量的增加而增加。  相似文献   

9.
田大听  谢洪泉 《合成化学》2002,10(6):493-497
用高锰酸钾/硫脲为引发剂,引发魔芋粉(KGM)与丙烯酰胺(AM)的接枝共聚。研究了引发剂浓度、单体浓度、酸度、反应温度、反应时间、反应介质以及KGM预处理方式等对接枝反应的影响,同时还研究了产物的水溶性及增稠性,并探讨了接枝反应机理。  相似文献   

10.
AA-AM-AN三元共聚物的合成及其溶液性能的研究   总被引:3,自引:0,他引:3  
采用自由基水溶液共聚法制备了水溶性丙烯酸-丙烯酰胺-丙烯腈共聚物。对聚合反应温度、引发剂用量、尿素用量、聚合物浓度、电解质浓度、剪切速率、温度等因素对聚合物溶液性能的影响进行了研究。结果表明,合成的水溶性聚合物具有良好的增稠作用及耐温抗盐抗剪切等性能。  相似文献   

11.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

12.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

13.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

14.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

15.
A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.  相似文献   

16.
A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.  相似文献   

17.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

18.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

19.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

20.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

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