摘要:

AbstractEsters of 2‐diazonaphthalenone sulfonic acid were examined by mass spectrometry using electron impact and chemical ionization techniques. Charactristic differences in the fragmentation patterns of positional isomers have been observed. In a manner analogous to photo‐induced decompositions, the diazoketo functional groups fragment by elimination of N2to form an indenoketene ion. An alternative process involves the apparent loss of 26 mass units from the molecular ion. The latter process is explained by evoking the abstraction of two hydrogen atoms following the loss of N2. With deuterium isotope labeling, it has been shown that the hydrogens are abstracted from the surface of the probe tip used for introduction of the samples into the mass spectrometer. It is concluded that an environment rich in hydrogen or proton‐donating properties promotes and enhances the incorporation of the hydrogen atoms and formation of the [M‐26] species at the expense of the ketene moiety, which is an important intermediate in the photoresist process. By extrapolation it may be inferred that the efficiency of the photolithographic process could be influenced by the availability of protons in the photoresist

ISSN:0021-8995    

DOI:10.1002/app.1987.070340201

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractThe refractive index of emulsions of polymers and copolymers may be estimated from absorbance readings with a UV‐visible spectrophotometer. Other information needed is the weight‐average particle diameter, from other techniques such as gradient disc centrifugation. A simple computer program matches the refractive index parameter so that calculated and experimental absorbances are equal at the given wavelength. The wavelength dependence of the polymer refractive index is readily obtai

ISSN:0021-8995    

DOI:10.1002/app.1987.070340202

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractThis paper provides a complete survey of the primary processes involved in typical oil‐and water‐soluble thioxanthane derivatives dissolved in sodium dodecyl sulfate micelles, in the presence of monomers and amines. Special emphasis is laid on the determination of the rate constants of the different processes and the absorption spectra of the transients. Relevant data are shown and discussed with reference to the effectiveness of these molecules as photopolymerization initiat

ISSN:0021-8995    

DOI:10.1002/app.1987.070340203

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractA strong pyrene emission was observed when certain block, alternate, and random butadiene–styrene‐based rubber films were subjected to intense UV irradiation in vacuum. Weak or no pyrene emission was obtained from the same films when they are irradiated in the presence of O2. A mechanistic scheme leading to pyrene formation in these samples is given together with qualitative explanation of the dependence of pyrene formation on sample composit

ISSN:0021-8995    

DOI:10.1002/app.1987.070340204

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractSpecific refractive index increments of ethylene/vinyl acetate copolymers have been masured in trichlorobenzene at 145°C. A relationship between these values and copolymer composition has been determined for use in light scattering measurements of weight‐average molecular weights of these materials. The data are also required for analysis of molecular weight distributions by size exclusion chromatography with light scattering detecti

ISSN:0021-8995    

DOI:10.1002/app.1987.070340205

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractThe interfacial behavior of a filler–plasticizer system was investigated using the pair poly(sodium methacrylate‐co‐divinylbenzene) beads–diisooctyl phthalate. The effect of various surface treatments of the filler was studied. These consist of a selective extraction of surfactant used in its preparation by emulsion copolymerization and in the adsorption of other types of surfactants. Changes in the compatibility between the two basic components were determined from measurements of the rate of penetration of the plasticizer through the filler bed, from the rheological behavior of concentrated suspensions and from the extractability of the filler from the plasticized PVC

ISSN:0021-8995    

DOI:10.1002/app.1987.070340206

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractBead‐shaped, divinylbenzene‐cross‐linked terpolymers, consisting of hemin (ferri‐protoporphyrin IX chloride), styrene, and 2‐methyl‐5‐vinylpyridine, were prepared by suspension polymerization in which all or part of styrene monomer was replaced with divinylbenzene. Analogous terpolymers of the cross‐linked and uncross‐linked formless types were also prepared by solution polymerization. All the terpolymers obtained were characterized by electron spin resonanance spectroscopy, scanning electron microscopy, and measurement of specific surface area. The characteristic of the adsorption of cyanide ion onto the terpolymer beads was investigated and compared with those adsorbed onto their analogs. The column separation of cyanide ion with the terpolymer beads was carried out to examine the ion‐adsorbing capacity. It was found that the suspension polymerization is just appropriate to prepare a cyanide ion exchanger i

ISSN:0021-8995    

DOI:10.1002/app.1987.070340207

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractAnalysis of sequence distribution (SD) in poly(vinyl alcohol‐co‐vinyl acetate) (p(VA‐VAc)) by the iodine complexation method (ICM) was investigated through the formation of a red complex of p(VA‐VAc) with iodine‐iodide. Differential thermal analysis (DTA) has been known to be a measure of SD and the ICM was also suggested to be valid for the SD analysis. ICM can be applied for samples of p(VA‐VAc) rich in VAc‐unit content, in which DTA could not be used. Results of SD analysis on p(VA‐VAc) by1NMR spectra were compared with those from ICM, and excellent agreement was found between data. The ICM can be applied as a convenient screening method for SD of p(VA‐VAc) as far as the red‐complex formation is concerned, and was shown to have much wider applicable range

ISSN:0021-8995    

DOI:10.1002/app.1987.070340208

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractTernary blends comprising bisphenol‐A polycarbonate (PC), the polyhydroxyether of bisphenol‐A (Phenoxy), and poly(ε‐caprolactone) (PCL) were found to be generally miscible at PCL levels greater than 60% by weight and to show multiple amorphous phases at lower PCL levels. The melting point depression of PCL in the miscible region of the ternary and in the miscible binary blends with PC and Phenoxy was examined to obtain the enthalpic interaction parameters,Bij, for each of the three binary interactions. The parameters associated with the miscible binary blends were negative, as expected, and indicated that PCL interacts more exothermically with Phenoxy than with PC. The parameter associated with Phenoxy/PC interaction was strongly positive as expected from the complete immiscibility shown by these materials. The interaction parameters were used to calculate the locus of compositions for which the heat of mixing is zero. The locus was found to agree well with the observed boundary between miscible and multiphase behavior in the ternary. This suggests that the phase behavior of ternary blends is largely determined by the same enthalpic considerations known to govern the phase behavior of binary

ISSN:0021-8995    

DOI:10.1002/app.1987.070340209

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY

摘要:

AbstractObservations and conclusions drawn from a modelN‐methylol reactant system have been used to study formaldehyde release from cotton fabric treated withN,N′‐dimethylol‐4,5‐dihydroxy‐ethyleneurea (DMDHEU). Reagent residues produced by DMDHEU in the presence of sodium bisulfate or zinc nitrate were found to be more complex than those formed from theN‐methylolpyrrolidone (NMP) reactant system, and the exact nature of some of the residues from DMDHEU could not be established. Zinc nitrate produces higher fixation of DMDHEU on cotton as compared to sodium bisulfate and also reduces formaldehyde release. As is the case with the NMP system, the lower amount of formaldehyde release with zinc nitrate catalyst is believed to be at least partially due to the formation of a complex between theN‐methylol reactant, DMDHEU, and zinc nitrate. The COCell bonds in both finishes resist acid‐catalyzed cleavage but cleavage of the NC bonds inN‐methylol groups (to release formadehyde) in the presence of acid is greater for the DMDHEU system than for the NMP system. Results with the DMDHEU and NMP systems are similar, but because of the complex nature of the products formed in the DMDHEU system it is very difficult to correlated formaldehyde release with specific chemical structures o

ISSN:0021-8995    

DOI:10.1002/app.1987.070340210

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1987

数据来源: WILEY