摘要:

The terpolymerization of acryionitrile, styrene, and pentabromophenyl acrylate in dimethylformamide solution was investigated. Experimental terpolymerization data agreed well with calculations using the Alfrey-Goldfinger equation. The relationship between monomer feed and terpolymer compositions are presented on triangular coordinate graphs, and the lines of unique and the lines of binary azeotropic composition were identified. No point of true ternary azeotropic composition was found but a “pseudoazeotropic” region was identified. The experimental results of the terpolymerization agreed well with the theoretical curves over a wide range of monomer composition up to high conversions. The influence of pentabromophenyl acrylate units on the thermal and flammability characteristics of the terpolymers are described.

ISSN:0022-233X    

DOI:10.1080/00222338408069461

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

The copolymerization of castor oil prepolymer (COP) with methyl methacrylate (MMA) has been accomplished at 75°C using a free radical initiator. The monomer reactivity ratios of MMA (r1) and COP (r2) were determined to be r1= 3.04 and r2= 0.605. With an increasing concentration of COP in the binary mixture, copolymers with decreasing molecular weight were obtained. The copolymers obtained were powdery substances soluble in many organic solvents.

ISSN:0022-233X    

DOI:10.1080/00222338408069462

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

In order to investigate the interaction between acrolein (AL) and acrylamide (AAm) on anionic copolymerization, the homopolymer-izabilities of AL in the presence of several p-substituted phenyl-acetamides such as p-nitroacetanilide, p-chloroacetanilide, acet-anilide, and p-methylacetanilide were investigated in tetrahydro-furan at 0°C using imidazole as an anionic catalyst. A linear co-relation was obtained by Hammett′ s equation as described by log R /R = 0.28σ. This result suggests that the homopolymeriz- P Po ability of AL is influenced by the structure of the amide compound. An increase of the additive propionamide (PAm) on the homopolym-erization of AL induced by the pyridine-water initiation system increased the polymerization rate R; however, it decreased the intrinsic viscosity [η] of poly-AL. From the measurement of infrared spectroscopy and elementary analysis, the presence of a chain transfer reaction between the poly-AL anion and PAm was found. These results support the presence of interaction between AL and AAm derivatives in the copolymerization system.

ISSN:0022-233X    

DOI:10.1080/00222338408069463

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Dark colored Cr(III), Co(n), and Ni(II) polychelates of 4,4′-(4,4′-biphenylylenebisazo)di(2-hydroxy acetophenone) have been prepared and characterized on the basis of their physicochemical properties. An octahedral stereochemistry was found for Cr(III) and Co (II) polychelates, while the Ni(II) polychelate is tetrahedral.

ISSN:0022-233X    

DOI:10.1080/00222338408069464

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

New linear and three-arm star polyisobutylenes carrying two and three terminal styryl endgroups, i.e., Fn= 2.0 and 3.0, respectively, have been prepared. The synthesis of these styryl-telechelic polyisobutylenes involved Friedel-Crafts alkylation by linear and/or three-arm star polyisobutylenes carrying tertiary chlorine endgroups of (2-bromoethyl)benzene or /β-bromoisopropylbenzene followed by de-hydrobromination. According to model studies,1H-NMR, and UV spectroscopy, the conversions are essentially quantitative. These new terminally di- and tri-styrenated polyisobutylenes may be useful for the preparation of block copolymers and as cross-linking materials.

ISSN:0022-233X    

DOI:10.1080/00222338408069465

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Styryl-telechelic polyisobutylenes (i.e., linear and three-arm star polyisobutylenes capped with polymerizable p-styryl endgroups St-PIB-St and St-PIB-St) have been copolymerized with vinyl ace State VAc or N-vinyl-2-pyrrolidone VP by conventional free radical techniques. The products obtained with St-PIB-St/VAc systems were soluble, most likely branched block copolymers of isobutylene IB and VAc, whereas those prepared with St-PIB-St/VP or St-PIB-St/VP Stcombinations were networks consisting of PIB and poly(N-vinyl-2-pyrrolidone) PVP sequences. That the copolymerization of St-PIB-St with VAc results in soluble products and that with VP yields networks is due to the very different reactivities of styrene with VAc and with VP. Hydrolysis of VAc units in PID-PV Ac block copolymers gave vinyl alcohol V A units, i.e., these products are branched block copolymers consistion of random VAc/VA composition of these soluble aphiphilic materials was determined from conversion and molecular weight data and by1H-NMR soectroscopy; their mechanical properties were examined by stress - strain measurements. The composition of amphiphilic PVP-PIB networks was calculated from conversion and elemental analysis data. These gels were founds to bind both water -soludle dyes (methyl orange) and hydrocarbons (benzene). The first binding constant K1that characterizes the binding of methyl orange by these PVP-PIB networks is one order of magnitude larger than that characteristic of the binding of this dye by cross - linked PVP or by serum albumin.

ISSN:0022-233X    

DOI:10.1080/00222338408069466

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

The polymerization of indene by constant potential electrolysis in dichloromethane was achieved at low temperatures. Molecular weights were found to be inversely proportional to polymerization temperature. The oxidation peak potential of indene in the (C4H9)4-NBF4-CH3CN electrolyte-solvent system was measured by cyclic voltammetry. Polymers which were produced electrochemically by constant potential electrolysis have the same spectral properties with those obtained by chemical methods.

ISSN:0022-233X    

DOI:10.1080/00222338408069467

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Coumarin and 3-aryloxycoumarin polymers were prepared by the Perkin reaction of salicylaldehyde-formaldehyde polymer with acetic anhydride and with simple and substituted phenoxy acetic acids, respectively. All the coumarin polymer samples were characterized by elemental analysis, IR spectrometry, and TGA. Coumarin polymer samples were screened for their antifungal activity against a variety of fungi.

ISSN:0022-233X    

DOI:10.1080/00222338408069468

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Fractionation of alkali lignins of the soda and sulfate pulping processes of Ricinus communis and bagasse was carried out by using successive equal concentrations of the alkaline reagent. Soda lignins were soluble in organic solvents, while the sulfate ones were sparingly soluble. Thus, two fractions of the sulfate lignins, soluble and insoluble, could be obtained from acetone. The different alkali lignin fractions were subjected to elemental and functional group analyses. For both Ricinus communis and bagasse, the carbon content of the fractions of the various types of lignin is in the order: soluble sulfate > soda > insoluble sulfate, while the methoxy is in the order: soda > soluble sulfate > insoluble sulfate. The phenolic OH content, as well as OH/C9of soda lignins of bagasse, are lower than those of soluble sulfate lignins. For Ricinus communis, the phenolic OH content and OH/C9is higher for some of the fractions (first three stages of cooking) of soda lignin than the corresponding fractions of kraft (sulfate) lignin, while the reverse takes place for the other fractions. For the same type of lignin, the fractions showed changes in their carbon, methoxyl, and phenolic OH contents. The change may be regular, i.e., increase or decrease with the order of stage of cooking, or irregular. Molecular weights of the different alkali lignins which are soluble in organic solvents ranged between 750 and 840.

ISSN:0022-233X    

DOI:10.1080/00222338408069469

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor

摘要:

Alkaline nitrobenzene oxidation of the different lignin fractions isolated from Ricinus communis and bagasse yielded mainly vanillin, followed by syringaldehyde and then p-hydroxybenzaldehyde. The number of the guaiacyl units is higher than the sum of both syringyl and p-hydroxyphenyl propane units in soda lignins and acetone-soluble sulfate lignins for both Ricinus communis and bagasse. For acetone-insoluble sulfate lignins, the number of guaiacyl units is less or equal to the sum of both syringyl and p-hydroxyphenyl propane units for both Ricinus communis and bagasse.

ISSN:0022-233X    

DOI:10.1080/00222338408069470

出版商:Taylor & Francis Group    

年代:1984

数据来源: Taylor