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1.
Aromatic polybenzothiazolamides were prepared by low temperature solution method by condensing the 2, 2'-diarnino-6, 6'-bibenzothiazole with four different acid chlorides in quantitative yield. These polymers were characterized by IR and NMR. Viscosities of these polyamides range from 0.42 to 1 dl/gm. All these polymers were stable upto 300℃in air.  相似文献   

2.
Polybutadiene (PB) was chlorinated with t-BuOCl without chain crosslinking and degradation togive chlorinated polybutadiene (Cl--PB) with active allylic chlorine atoms on the backbone. Comb-shaped PB was prepared by coupling of Cl--PB with "living" PB anions in a mixed solvent of cyc-lohexane and tetrahydrofuran. Characterization by GPC and osmometry showed that purifiedproducts were welldefined comb-shaped PB composed of low polydispersity backbone chain andrandomly distributed grafts of uniform length. The averagr number of branches could be variedin a wide range to meet the needs of structure-properties relationship studies.  相似文献   

3.
SYNTHESISANDCHARACTERIZATIONOFPOLYURETHANELATEX¥QingYeZHOU;HanLI;MouDaoSONG;BangHuaZHANG;BingLinHE(InstituteofPolymerChemistr...  相似文献   

4.
A series of nine Pd(0)complexes(L)Pd(L')[L=bis(diphenylphosphino)methane(dppm),1,2-bis(diphenylphosphino)ethane(dppe),and 1,1'-bis(diphenyl-phosphino)ferrocene(dppf),respectively;L=dibenzylideneacetone(dba),2,3,5,6-tetrachloro-1.4-benzoquinone(q)and 2,3-dichloro-1,4-naphthoquinone(nq)]were synthesized and characterized by means of elemental analyses,IR,UV,1~H-NMR and~(31)P-NMR spectra.The redox wave peak potentials of the ferrocenylgroup of complexes with dppf were measured by using CV method.Results showedthat all the diphosphorus ligands behaved as chelating bidentate ligand anddba,q,nq were coordinated to the Pd(0)atom through their C=C moieties,nottheir carbonyl ones.Analytical data also showed that there were interactionsbetween the two different ligands in each complex.  相似文献   

5.
Titanocene polymer derivatives with potential antitumor properties were synthesized by interfacial condensation. The preformed polymers used are PAA (polyacrylic acid), CPSMA (1:1 alternating copolymer of styrene and maleic anhydride) and DVEMA (1:2 copolymer of divinyl ether and maleic anhydride). The ratio of practical and theoretical titanium content is 73.6%, 92.2% and 86.2% for PAA, CPSMA and DVEMA polymer derivatives respectively. The IR spectra of the polymer derivatives possess the characteristic absorptions of titanocene. XPS (X-ray photoelectron spectroscopy) of O_(1s) and Ti_(2p3/2) supports the existence of Ti-O bonding.  相似文献   

6.
<正> A dirnethylamine-occluding galloarsenate,designated as GaAsO4-2,was prepared hydrothermally and determined structurally by single crystal X-ray diffraction technique. The compound crystallizes in nionoclinic space group P21/n with unit cell con-stants:a=18. 011(4),b=10. 466(4),c=19. 035(4)A ,β=113. 97(6)°,V= 3278. 81 A3,Dc =3. 06gcm-3,Z=4. The three-dimensional net of GaAsO4-2 constructed by Ga, As,O and F atoms has three kinds of open channels. One is formed by 10-T (T = Ga or As)rings packed along [010],the other two are formed by zigzag packing of 8-T rings a-long [100]and [001]. The dimethylamine molecules as templates are located inside the 10-T channels with their NH group pointing toward the channel wall.  相似文献   

7.
Cis-platinum complexes used as antitumor drugs were attached onto preformed polymers toreduce the toxicity. Either alternating copolymer of styrene and maleic anhydride (CPSMA) orpolyacrylic acid (PAA) is readily dissolved in alkaline solution. The cis-platinum complexes areeasily converted into water soluble species when treated by silver nitrate in water. The expectedproducts could be obtained when the two aqueous solutions were brought together. The productswere characterized by elementary analysis, IR and XPS. The polymer derivatives could exchangeligands with nucleophilic groups in biological environment and also exhibit antineoplastic activity.  相似文献   

8.
Block polymer of alternating copolymers, poly[(ST-a-MA)-b(IP-a-MMA)-b-(ST-a-MA)](I), has been synthesized in the presence of AlEt_(1.5)Cl_(1.5),by using Mn_2(CO)_(10)/CBr_4. initiation system.The GPC results indicate that there is no unreacted prepolymer in I purified by precipitation andfractionation. The study of NMR shows that every block of polymer I has alternating structure. The dynamicmechanical properties of I measured by torsional braid method indicate that the polymer has two T_g s,being 38 and 75℃, respectively. The transmission electron micrographs of I show they have two phasestructure and the domain size increases with increasing molecular weight of hard block.  相似文献   

9.
A new Schiff base diol,4,4'-[3-methoxy-4-(2-hydroxy)-ethoxy]azomethine biphenyl(MHAMB),was synthesized,which was copolynerized with PEC-600 and TDI to obtain a blook polyurethane.Themonomer and the polymer were charaoterized by eaploying IR,NMR and elemental analysis,Liquidcrystallline phase transitions were studied by polarized aiorograph.  相似文献   

10.
An ordered ladder polyester (LPE) was first synthesized through the ladder superstructure (LS) constructed by concerted interactions of hydroxyl- and aramide-based H-bonding and p-terphenyl (TP)-based π-stacking by dehydrochlorination condensation using phosgene (COCl2) as coupling agent. LPE was characterized by GPC, FTIR, NMR, XRD, DSC and AFM. Among them, a distinct image of regularly linear alignment corresponding to the ladder main chain of LPE was first revealed by high-resolution AFM.  相似文献   

11.
A series of novel aluminophosphates,named AlPO_4-CJ_n(n=2-5),has beensynthesized hydrothermally from R-Al_2O_3-P_2O_5-H_2O systems(R=organic amine molecules),and characterized by means of X-ray powderdiffraction,infrared,SEM,XPS,composition and thermal analyses.  相似文献   

12.
An improved procedure was used to prepare the asymmetric tripyrrane-containing macrocycles,The yield was over 85% These maerocycles could be oxidized to the methine bridled 23 electronaromatic cadmium(Ⅱ)complexes by reating with cadmium chloride in the presence of air and theiratructures were characterized.  相似文献   

13.
14.
NiCl_2(bpy) catalyzed polycondensation between p-dibromobenzene and m-dibromobenzene has been carried outunder vdrious conditions. The polycondensation endows the copolymer with an M_n of 2300 (by GPC, polystyrene standards)and good solubility in organic solvents. The fluorescence spectra of the copolymer measured with tetrahydrofuran solutionshows an emission maximum (λ_(max)) at 372.8 nm, whereas for the film the maximum shifts to 436.6 nm.  相似文献   

15.
THESYNTHESISANDCHARACTERIZATIONOFANOVEL MIXED-VALENCEISOPOLYVANADATEJiaNingXU;GuoYuYANG;WenYingMA;ZhiZhongSun;JiQingXU(Depart...  相似文献   

16.
Copolymer of divinyl ether and maleic anhydride (DVE-co-MA) derivatives of cis-platinum complexes were synthesized and characterized by elementary analysis, IR and XPS ( X-ray photoelectron spectroscopy). The behavior of the products in biological environment was also studied. UV-visible and fluorescence spectra show that these polymer derivatives are able to exchange ligands with selected nucleophilic groups in biological environment.  相似文献   

17.
A series of novel mesogenic polyamides containing a flexible pendent side group wassynthesized by solution condensation polymerization. The new monomers, diacids and di-amines containing flexible elements of diferent lengths, were also synthesized and character-ized by ~1HNMR, mass spectroscopy and elemental analysis. The polymers were character-ized by viscosity measurements, differential scanning calorimetry (DSC), X-ray diffiactionand polarizing optical microscopy These studies revealed that polyamides containingflexible elements of a sufficient length exhibited thermotropic liquid crystalline(LC) pro-perties. The melting temperatures of this series of polymers were particularly sensitive tothe length of the flexible segment on the main chain and that of the flexible pendent esterside chain. Lyotropic LC behaviours were also observed in solution.  相似文献   

18.
1. INTRODUCTION The new kinds of heteroaromatic polymers have been important topics in polymer science fields since they were developed at 1960s in order to meet demands for heat-resistant plastics for space and military applications. Because heteroaromatic polymers exhibit excellent thermal and chemical stability, outstanding electrical and mechanical properties, good solvent resistance, and dimensional stability, these polymers have found usage as adhesives, coatings, matrix resins, film…  相似文献   

19.
A new silazane oligomer containing cyclotrisilazane was synthesized by KH-catalyzed dehydro-coupling reactionsbetween diphenylsilane and 1,1,3,3,5,5-hexamethylcyclotrisilazane (D_3~N).  相似文献   

20.
The montmorillonites (MMTs), layered, smectite-type silicates, were premodified by two different methods priorto the polymer melt intercalation. In one case MMTs were modified with cetyltrimethylammonium bromide (CTAB), andtermed as organomontmorillonites (OMMTs); in the other case MMTs were modified by nylon, and the products were calledmodified montmorillonites (MMMTs). The effects of CTAB and nylon on the MMTs were investigated by using TG andWAXD. The results show that interlayer spacings of CTAN and nylon modified MMTs are larger than that of sodium MMTs.Then, polyamide 66 (PA 66)/MMT nanocomposites were obtained through the method of melt intercalation of polymers. Thenanocomposites were characterized by WAXD, TEM and Molau experiments. The results indicate that the MMTs dispersehomogeneously in the PA 66 matrix. The mechanical properties of nanocomposites, such as tensile properties and flexuralproperties, were also measured and show a tendency to increase with increase of MMT content and reach the maximumvalues at 5phr MMT content. The heat distortion temperature (HDT) of the nanocomposites (7 phr) is about 32 K higher thanthat of pure PA 66.  相似文献   

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