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1.
Some copolymers of 2,4-dichlorophenyl acrylate (2,4-DCPA) with styrene (St) of different teed compositions were prepared by tree radical polymerization technique using 2,2′-azobisisobutyronitrile (AIBN) as an initiator,and the copolymers were characterized by IR spectroscopy.The copolymer composition obtained by UV-spectra led to determination of reactivity ratio by employing Fineman-Ross (F-R) and Kelen-Tudos (K-T) methods.Average molecular weight,as well as intrinsic viscosity,was obtained by vapor pre...  相似文献   

2.
丙烯腈,丙烯酸甲酯,衣康酸三元共聚竞聚率的测定   总被引:2,自引:0,他引:2  
本文主要论述三种单体以不同配比在硫氢酸钠水溶液中进行共聚合,探讨其反应规律,用电子计算机由三元共聚组成方程求出了反应体系中三个单体的六个竞聚率,建立了配料组成、共聚物的组成及计算的竞聚率之间的关系,并对三元共聚竞聚率进行了分析。  相似文献   

3.
Synthesis and characterization of the copolymers (PAG) of α-methyl styrene (AMS) and glycidyl methacrylate (GMA) are presented. The copolymers of PAG were characterized by gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (1H-NMR) and thermogravimetery (TG). Based on the copolymer compositions determined by 1H-NMR, the reactivity ratios of AMS and GMA were found to be 0.105 ± 0.012 and 0.883 ± 0.046 respectively by Kelen-Tiidos method. TG revealed that thermal stability of the copolymers decreased with increasing the AMS content in the copolymers, which indicated that the degradation was mainly caused by the chain scission of AMS-containing structures. Under heating, the copolymers depolymerize at their weak bonds and form chain radicals, which could further initiate other chemical reactions.  相似文献   

4.
The copolymerizations of methyl acrylate (MA) with different N- arylmethacrylamide (N-ArMA) were carried out in benzene solution by free radical initiation. The compositions of the copolymers were deter mined by ~1H NMR method. The monomer reactivity ratios were calculated by the Fineman-Ross (F-R) method. The reactivity ratios and the activity of various N-ArMA with MA were investigated.  相似文献   

5.
2-Acrylamido-2-methy1-1-propanesulfonic acid(AMPS),and maleic acid(MA)copolymerized with different feed ratios using N,N-dimethylformamide as a solvent and benzoyl peroxide(Bz_2O_2)as an initiator at 70℃.Structure and composition of copolymers for a wide range of monomer feed were determined by elemental analysis(content of N for AMPS-units).Monomer reactivity ratios for AMPS(M_1)-MA(M_2)pair were determined by the application of conventional linearization methods such as Fineman-Ross(F-R),Kelen-Tüd(?)s(KT)and Extended Kelen-Tüds(EKT)and a nonlinear error invariable model method using a computer program RREVM.The characterizations were done by Fourier transform infrared spectroscopy(FTIR),differential scanning calorimetry(DSC)thermal gravimetry analysis(TGA),and and X-ray diffraction.The antimicrobial effects of polymers were also tested on various bacteria,and yeast.  相似文献   

6.
通过自由基聚合反应得到了2,5-二[5-(对癸氧基)苯基)-1,3,4-噁二唑]乙烯基苯和乙烯基咔唑的无规共聚物.研究了共聚物组成与热性能关系;实验结果表明,随着乙烯基咔唑量的增加,共聚物的荧光量子产率会下降;共聚物与相应的均聚物相似,它们具有相似的光致发光波长.  相似文献   

7.
Water-soluble A-B block copolymers of 2-perfluoroethyl-2-oxazoline or 2-pentyl-2-oxazoline as hydrophobic monomers and 2-methyl-2-oxazoline as hydrophilic monomer were prepared by means of the living cationic ring-opening polymerization. The polymerization was initiated with N-methyl-2-(1-naphthyl)-2-oxazolinium trifluoromethanesulfonate as fluorescence label followed by sequential addition of the hydrophobic and the hydrophilic monomer. The polymerization was monitored by 1H NMR spectroscopy and gel permeation chromatography (GPC) measurements. The results revealed that fluorophilic block copolymers can be prepared by this method while lipohilic block copolymers are not accessible by this monomer sequence. Micelle formation of the fluorophilic block copolymers in aqueous solution was studied by means of steady-state fluorescence spectroscopy which confirmed strong intermolecular excimer formation of the terminal bounded naphthalene moiety. In chloroform as a good solvent for both blocks, only monomer fluorescence could be observed.  相似文献   

8.
The copolymerization of DL-LA and 3-BMG was carried out in bulk with Stannous 2-ethylhexanoate as thecatalyst. A series of copolymers with pendant protected groups were obtained and characterized by ~1H-NMR and GPCanalysis. The monomer reactivity ratios were evaluated by the Fineman-Ross method and the Kelen-Tudos method and foundto be r_(BMG) = 1.96 and r_(LA) = 0.37, respectively.  相似文献   

9.
The oxidative polycondensation reaction conditions of 4-[(4-hydroxybenzylidene)amino]phenol(4-HBAP)were studied with H_2O_2,air oxygen and NaOCl in an aqueous alkaline medium between 50 and 90℃.The structures of the obtained monomer and polymer were confirmed by FT-IR,UV-Vis,~1H-and ~(13)C-NMR and elemental analysis.The characterization was made by TG-DTA,size exclusion chromatography(SEC)and solubility tests.At the optimum reaction conditions,the yield of poly[4-(4-hydroxybenzylidene amino)phenol](P-4-HBAP)was found to be 48.3%(for H_2O_2 oxidant),80.5%(for air O_2 oxidant)and 86.4%(for NaOCl oxidant).According to the SEC analysis,the number-average molecular weight(M_n),weight-average molecular weight(M_w)and polydispersity index(PDI)values of P-4-HBAP was found to be 8950,10970 g mol~(-1) and 1.225,respectively,using H_2O_2;and 11610,15190 g mol~(-1) and 1.308 respectively, using air O_2 and 7900,9610 g mol~(-1) and 1.216,respectively,using NaOCl.According to TG-DTA analyses,P-4-HBAP was more stable than 4-HBAP against thermal decomposition.The weight loss of P-4-HBAP was found to be 49.27% at 1000℃. The highest occupied molecular orbital(HOMO)and the lowest unoccupied molecular orbital(LUMO)values calculated from electrochemical measurement.Electrochemical energy gaps(E′_g)of 4-HBAP and P-4-HBAP were found to be-5.46, -5.28;-2.26,-2.67;3.20 and 2.61 eV,respectively.According to UV-Vis measurements,optical band gap(E_g)of 4-HBAP and P-4-HBAP were found to be 3.34 and 3.01 eV,respectively.Also,antimicrobial activities of 4-HBAP and P-4-HBAP were examined against selected some bacteria.The electrical conductivity of the polymer was measured after doping with iodine.  相似文献   

10.
1NTRODUCTIONTheacrylateterpolymer--supPOrtedsulfideplatinumcomplexanddisulfideplatinumcomplex['--2]werestudiedinthehydrosilylationofolefins.Itisfoundthattheyhavehighcatalyticactivityandreusedproperties.LiuXFetal.[3)synthesizedselena--crowneitherplatinumcomplexesandreportedtheircatalyticactivityofhydrosilylation.Clarketal.[4)reportedthatthecatalyticactivityofPiLL'Clz(L=PPh2,L'=S,N)ishigherthanthatofPtLZC12orPtL'ZC12inhydrosilylation.Inthispaper,wereportthesynthesisofanewacrylatete…  相似文献   

11.
Electrophilic trisubstituted ethylene monomers, ring-substituted methyl 2-cyano-3-phenyl-2-propenoates, RC6H4CH?C(CN) CO2CH3 (where R is 4-C2H5O, 4-C3H7O, 4-C4H9O, 3-C6H5O, and 3-CN), were prepared and copolymerized with styrene. The monomers were synthesized by the piperidine catalyzed Knoevenagel condensation of ring-substituted benzaldehydes and methyl cyanoacetate, and characterized by CHN elemental analysis, IR, 1H- and 13C-NMR. All the propenoates were copolymerized with styrene (M1) in solution with radical initiation (AIBN) at 70°C. The compositions of the copolymers were calculated from nitrogen analysis and the structures were analyzed by IR, 1H- and 13C-NMR. The order of relative reactivity (1/r1 ) for the monomers is 3-CN (1.21) > 3-C6H5O (1.16) > 4-C2H5O (0.94) > 4-C3H7O (0.8305) > 4-C4H9O (0.616). The high T g's of the copolymers (> 130°C) in comparison with that of polystyrene indicate a substantial decrease in the chain mobility of the copolymers due to the high dipolar character of the trisubstituted monomer unit. Gravimetric analysis indicated that the copolymers decompose in the range 300–400°C.  相似文献   

12.
本文报道了稀土与丙氨酸-N-荒酸镍[H2NiL2]多核配合物的合成和表征。通过元素分析确定配合物的组成为RE2(NiL2)3·xH2O(RE=La、Nd、Sm-Er、Yb;x=1、4、8),并研究了配合物的摩尔电导、红外光谱和核磁共振氢谱。配合物体外抗癌活性及抑菌活性的测定结果表明,丙氨酸-N-荒酸镍及其稀土多核配合物均具一定的抗癌、抑菌活性。  相似文献   

13.
研究了聚氧乙烯大单体与甲基丙烯酸甲酯及丙烯酸丁酯的三元共聚中大小单体的聚合速率和引发剂用量、大单体分子量及投料比对接枝效率及共聚物分子量的影响。用IR、~1HNMR、VPO、膜渗透压计及DSC等明确了经纯化过的共聚物为规整接枝共聚物,平均接枝数为10左右。研究其性能表明,该共聚物有一定的结晶度、良好的乳化性及相转移催化性,并呈现热塑性弹性体的性质。  相似文献   

14.
15.
Copolymers of 4-cinnmoylphenyl methacrylate (CPMA) with glycidyl methacrylate were synthesized in methyl ethyl ketone solution using benzoyl peroxide as initiator at 70 ± 1°C. They were characterized by UV, IR, 1H-NMR, and 13C-NMR spectra. Their compositions were determined by 1H-NMR technique. The monomer reactivity ratios were determined by the Fineman-Ross and Kelen-Tüdös methods. The molecular weights ([Mbar]w and [Mbar]n) of the polymers were determined by GPC technique. Thermogravimetric analysis of the copolymers were carried out in air. The Tg of the polymers were determined by differential scanning calorimetry. The photocrosslinking properties of the homo and copolymers were also discussed.  相似文献   

16.
17.
从2-羰基丙酸(吡啶-4-甲酰基)腙(H2PPFH)合成了13种组成为RE2(PPFH)3·nH2O(RE=La-Yb,n=2~3)的稀土腙固体配合物。通过红外、紫外、元素分析,电导及核磁共振谱等方法对其进行了表征。经药理实验发现配合物Eu2(PPFH)3·3H2O具有抗肿瘤活性。  相似文献   

18.
不同软段长度PBT-co-PBS-b-PEG嵌段共聚物的合成与表征   总被引:6,自引:0,他引:6  
用熔融缩聚法合成了一系列具有不同软段长度的聚对苯二甲酸丁二酯 (PBT) co 聚丁二酸丁二酯(PBS) b 聚乙二醇 (PEG)嵌段共聚物 (PTSG) ,考察了PEG分子量 (Mn(PEG) )及PBS摩尔分数 (MPBS)对材料性能的影响 实验表明 ,随Mn(PEG)增加 ,缩聚反应时间延长 ,所得产物分子量均呈较为对称的单峰分布 ,多分散性指数小于 2 0 硬段序列结构分析显示 ,随MPBS 增加 ,PBT平均序列长度减小 ,而PBS平均序列长度增加 ,二者呈无规分布 .受组成及硬段平均序列长度变化影响 ,材料内部呈微观相分离状态 ,DSC曲线上可分别观察到软、硬段熔点及玻璃化转变温度 ;硬段熔点及结晶度随MPBS升高而降低 ,主要是受其平均序列长度变化及共晶作用所致 .材料断裂延伸率及降解速率均随Mn(PEG)及MPBS增加而增加 ,可见提高软段长度及降低硬段结晶度等均能有效改善共聚物高分子链的柔韧性及亲水性 ,赋予共聚物更好的降解性能 .  相似文献   

19.
The oxidative polycondensation reaction conditions of 4-m-tolylazomethinephenol (4-TAMP) in the presence of air O2 and NaOCl as oxidants were studied in an aqueous alkaline medium between 50 and 90℃. The structures of the obtained monomer and oligomer were confirmed by FT-IR, UV-Vis, ^1H- and ^13C-NMR and elemental analysis techniques. The physical characterization was made by TG-DTA, size exclusion chromatography (SEC) and solubility tests. At the optimum reaction conditions, the yield of oligo-4-m-tolylazomethinephenol (O-4-TAMP) was found to be 62.50% (for air O2 oxidant) and 90.0% (for NaOCl oxidant), respectively. According to the SEC analysis, the number-average molecular weight (Mn), weight-average molecular weight (Mw) and polydispersity index (PDI) values of O-4-TAMP were found to be 2310, 2610 g tool 1 and 1. 13, respectively, using air O2, and 1390, 1710 g mol^-1 and 1.23, using NaOCl, respectively. According to TG-DTA analyses, O-4-TAMP was more stable than 4-TAMP against thermal decomposition. The weight losses of 4-TAMP and O-4-TAMP were found to be 68% and 58% at 1000℃. Electrical conductivity of the O-4-TAMP was measured, showing that the polymer is a typical semiconductor. Electrochemically, the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) and electrochemical energy gaps (E'g) for 4-TAMP are -5.96, -3.22 and 2.74 eV, respectively. The HOMO, LUMO and (E'g) for O-4-TAMP are -5.78, -3.44 and 2.34 eV, respectively. According to UV-Vis measurements, optical band gaps (Eg) of 4-TAMP and O-4-TAMP were found to be 3.45 and 3. 1 0 eV, respectively.  相似文献   

20.
The optimum reaction conditions of the oxidative polycondensation of 2-(thien-2-yl-methylene)aminophenol (2-TMAP) has been accomplished by using air O_2,H_2O_2 and NaOCl oxidants in an aqueous alkaline medium between 20℃and 90℃.The structures of the monomer and oligomer were confirmed by FT-IR,UV-Vis,~1H-NMR and ~(13)C-NMR and elemental analysis.TGA-DTA,size exclusion chromatography(SEC) techniques and solubility tests were applied for characterization.The ~1H-NMR and ~(13)C-NMR data show that the polyme...  相似文献   

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