摘要:

Copolymerization parameters of some halogen substituted phenolic monomers have been determined by the linear graphical method of Kelen and Tüdös. The order of reactivity of p-chlorophenol, p-bromophenol and p-iodophenol is found to be the reverse of the order of electronegativity of their halogen substituents when they are copolymerized with p-hydroxy-benzoic acid. On copolymerization with p-cresol, these halogen substituted phenols have reactivity in the same order as the electronegativity of their substituents. This reversal of reactivity of phenolic monomers has been interpreted in terms of (1) opposite polarization caused by electrophilic or nucleophilic substituents present in the common monomers, and (2) the magnitude of their resonance stabilization.

ISSN:0022-233X    

DOI:10.1080/00222338108056817

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Some three-component phenolic block copolymers have been prepared from the following three monomeric units: p-amino-phenol, p-chlorophenol, and p-creso1. Homopolymerization of these monomers has been done with formaldehyde in the presence of acid catalyst. The homopolymer samples were then condensed together with stoichiometric quantities of formaldehyde and acid catalyst. Several samples of the copolymers were also prepared by changing the composition of the feed during homopolymerization. Composition, DP, and the average number of a particular monomeric uhit in a block of a copolymer chain has been deduced from electrometric titration curves of the copolymers in nonaqueous media.

ISSN:0022-233X    

DOI:10.1080/00222338108056818

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

The stability constants of ternary Co(II), Ni(II), Zn(II), or Cd(II) complexes containing 2,2′-bipyridyl (bipy) or 1,10-phenanthroline (phen) as a primary ligand and N-phenyl-2-mercaptopropion-amide (PMP) as a secondary ligand in a 1:1:1 molar ratio were determined using the Irving-Rossotti pH-titration technique in a 70% (v/v) dioxane-water mixture (I=0.1 M NaC104; 30 ± 1°C) in an inert atmosphere. The stability of these ternary complexes is discussed on the basis of π -accepting qualities of the sulfur ligand and the participating heteroaromatic N-base.

ISSN:0022-233X    

DOI:10.1080/00222338108056819

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Chelate polymers of Cu(II), Ni(II), Co(II), Zn(II), and Mn(II) with 4,4′-bis(m-formyl-p-hydroxy phenyl) biphenyl sulfone have been prepared. All the chelates are dark, amorphous, and insoluble in common organic solvents. The probable octahedral structures of the complexes were determined on the basis of their IR and electronic spectral data in conjunction with their magnetic susceptibility data. The ligand field parameters have been determined for Ni(II) and Co(II) polychelates using ligand-field theory of spin-allowed transitions.

ISSN:0022-233X    

DOI:10.1080/00222338108056820

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Poly-N-vinylcarbazole has been chemically modified through the reaction of poly(N-vinylcarbazole-3,6-dicarboxylic acid) and 1-naphthol in the presence of concentrated sulfuric acid to a polyfunctional cation exchanger of improved thermal properties. The compound has been characterized in respect of its structure, polyfunctionality, ion exchange capacity, and thermal stability.

ISSN:0022-233X    

DOI:10.1080/00222338108056821

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

Various diene polymers have been modified at room temperature via the ene reaction with 4-substituted-1,2,4-triazoline-3,5-diones. The resulting modified polymers were characterized by means of IR spectroscopy, nuclear magnetic resonance, differential scanning calorimetry, and solubility tests. Physical properties measurements support the assumption that the highly-polar pendant urazole groups play an important role in both inter-molecular and intramolecular hydrogen bonding interaction, and accordingly give thermoplastic properties to the modified polymers. Changes in the thermal analysis and solubility character of the modified polymers agree fairly well with this assumption. The modified polymers remain soluble in suitable solvents because of the physical nature of the association between molecules.

ISSN:0022-233X    

DOI:10.1080/00222338108056822

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor

摘要:

This is a scanned image of the original Editorial Board page(s) for this issue.

ISSN:0022-233X    

DOI:10.1080/00222338108056806

出版商:Taylor & Francis Group    

年代:1981

数据来源: Taylor