ISSN:0022-233X    

DOI:10.1080/00222337008081729

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

Methylthioethyl acrylate, prepared by ester exchange from methylthioethanol and methyl acrylate, behaves in copolymerization like a typical acrylate ester such as butyl acrylate. This monomer can be alkylated to yield corresponding sulfonium monomers. With dimethyl sulfate, (2-acryloxyethyl) dimenthylsulfonium methyl sulfate is obtained. This latter monomer has a predictable lower relative copolymerization rate with alkyl acrylates than methylthioethyl acrylate. Water-soluble sulfonium polymers are polymeric cations and can act effectively as flocculants.

ISSN:0022-233X    

DOI:10.1080/00222337008081730

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

Polymerization of anhydrous ethylenimine proceeds to completion with destruction of the terminal 1-aziridinyl group at relatively low molecular weight. In the absence of evidence for end groups, it is suggested that the chain terminating process is the formation of large rings composed of repeating CzHs N units.

ISSN:0022-233X    

DOI:10.1080/00222337008081731

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

A number of reporter molecules of the structure R-(CH2)n-N+(CH3)2(CH2)mN+(CH3)3·2Br−, where R is a chromophore absorbing in the 300–500 mp region, have been synthesized. The effect of DNA and RNA on the absorption, induced circular dichroism, and proton magnetic resonance spectra is reported. A red shift and a hypochromic effect on the absorption spectra of the bound chromophore is observed. In all cases where R is an “unsymmetrical” 4-nitroaniline chromophore, it is found that DNA and RNA induce an opposite CD in the absorption band of the bound reporter molecules. These results together with PMR studies are interpreted in terms of the structure of the nucleic acid systems in solutions.

ISSN:0022-233X    

DOI:10.1080/00222337008081732

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

This paper is a literature survey of quaternary ammonium, sulfonium, and phosphonium polymers.

ISSN:0022-233X    

DOI:10.1080/00222337008081733

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

This paper summarizes some of the experimental procedures used for making homopolymers and copolymers of dimethyldiallylammonium chloride, along with a discussion of some of the experimental variables such as effects of catalyst ratio, monomer concentration, and impurities. Also discussed are some of the procedures used for evaluation of the polymers and copolymers in flocculation and sludge dewatering.

ISSN:0022-233X    

DOI:10.1080/00222337008081734

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

The flocculating effectiveness of mixtures of various fatty amines with colloidal chrysotile asbestos was studied to determine the extent to which the amine and the asbestos act in concert as polycations. Tallow 1,3-propylene diamine was the principal amine studied, although other fatty amines showed similar properties. Aqueous solutions of the amine defibrillate the chrysotile into primary tubules about 250 Å in diameter and several microns in length. It is believed that the amine molecules adsorb on the surface of the chrysotile tubules, promoting their defibrillation and the high stability of the resultant dispersion. The flocculating effectiveness of the arnine/asbestos mixtures was determined on several neutral or anionic mineral suspensions including titania and kaolin by measuring sedimentation rate and volume. The flocculating effectiveness was also determined on a suspension of hydrophilic organic matter, partially digested diluted municipal waste, by measuring filtration rate. The amine/asbestos mixtures are more effective flocculants than either the amine or the asbestos alone. Moreover, in contrast to behavior frequently observed with conventional polymeric flocculants, the mixtures show little tendency to restabilize the suspended matter at higher than optimum concentrations.

ISSN:0022-233X    

DOI:10.1080/00222337008081735

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor

摘要:

A wide variety of diunsaturated phosphonium salts have been synthesized in order to determine whether or not such structures undergo cyclopolymerization. As intermediates for these monomers, a number of previously unreported unsaturated phosphines have been prepared and characterized. Polymerization studies using a wide variety of free radical initiating conditions led to polymers in those cases which were predicted to undergo cyclopolymerization leading to five-, six-, or seven-membered rings with one exception. The properties of the polymers are consistent with the cyclopolymerization mechanism. The conversion of poly(diallyldiphenylphosphonium bromide) to polfidiallyldiphenylphosphine oxide) offers additional evidence for cyclopolymerization. Di-3-butenyldiphenylphosphonium bromide, a monomer functionally capable of forming a polymer containing an eight-membered ring, did not polymerize. Divinylphenylphosphine was found to undergo copolymerization with acrylonitrile in accordance with the cyclo-copolymerization mechanism.

ISSN:0022-233X    

DOI:10.1080/00222337008081736

出版商:Taylor & Francis Group    

年代:1970

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:10.1080/00222337008081728

出版商:Taylor & Francis Group    

年代:1970

数据来源: Taylor