摘要:

AbstractN‐Phosphorylated 3‐amino‐1,2,4‐triazoles, prepared from the herbicide amitrole by acylation with phenyl‐ and 4‐nitrophenyl phosphorodichloridate, respectively, as well as with phosphoryl chloride were reversibly linked to poly(vinyl alcohol) designed for controlled release of the active agent.4‐N,N′‐Dimethylaminopyridine was used as catalyst for the polymeranalogous esterification reactions. IR,1H‐NMR, and31P‐NMR analyses of polymers suggest attachment of the herbicide moiety as pendant groups bound via phosphate groups at the ring nitrogen. Comparative hydrolysis studies demonstrated the influence of the substitution degree of PVAL and of the modification of the phosphorus‐to‐triazolide linkage upon the hydro

ISSN:0003-3146    

DOI:10.1002/apmc.1985.051350101

出版商:Hüthig&Wepf Verlag    

年代:1985

数据来源: WILEY

摘要:

AbstractGraft copolymers of six cereal starches with polyacrylonitrile have been prepared and investigated. The molecular weights, the frequencies of grafting and the absorbencies of the saponified products are almost independent of the source of granular starches. The percent yield and percent add‐on of graft copolymers from gelatinized starches are almost the same as those from granular cereal starches. However, their molecular weights, corresponding frequency of gelatinized starch graft copolymers have increased five times, while absorbency is doubled. The effects of initiator monomer concentration, and of dilution are discusse

ISSN:0003-3146    

DOI:10.1002/apmc.1985.051350102

出版商:Hüthig&Wepf Verlag    

年代:1985

数据来源: WILEY

摘要:

AbstractThe copolymerization of styrene with divinylbenzene in the presence of tri‐n‐butylphosphate or a mixture of di‐2‐ethylhexylphosphoric acid and chlorobenzene was studied in order to perform porous networks, solvent impregnated copolymers, etc. The diluents behave as strong precipitants allowing to prepare permanent porous copolymers having low contents of the crosslinking agent.The effects of dilution, crosslinking degree, and nature of diluent on the porosity as well as on the uptake coefficients, the specific surface area, and the average pore diameter, were studied to elucidate the manner in which such inert compounds contribute to the formation of porous n

ISSN:0003-3146    

DOI:10.1002/apmc.1985.051350103

出版商:Hüthig&Wepf Verlag    

年代:1985

数据来源: WILEY

摘要:

AbstractThe Cole‐Cole method has been employed for an analysis of the dielectric relaxation data, obtained by Bhattacharya, of a shellac‐urea‐formaldehyde resin (SUF) in the temperature range 30–100°C. Three relaxation processes were observed for temperatures 30 to 50°C. At 60°C, two relaxation processes were noticed. The relaxations at 70°C and above represented typical Cole‐Cole type. The static dielectric constant, relaxation time and distribution parameter of SUF were found to be greater than those of the unmodified shellac. Marked changes in the above mentioned parameters were observed during a rise of temperature from 70 to 100°C. The results of the present study indicate that some rearrangement in the tertiary disposition of the resin molecules takes place during the rise of temperature fr

ISSN:0003-3146    

DOI:10.1002/apmc.1985.051350104

出版商:Hüthig&Wepf Verlag    

年代:1985

数据来源: WILEY

摘要:

AbstractDe nombreux sensibilisateurs et amorceurs ont été testés pour la polymérisation d'un acrylate, sous irradiation visible. Les rôles de chaque constituant du système, des concentrations et des conditions d'irradiation (puissance du faisceau et focalisation) sont reportés. Les meilleurs résultats sont obtenus avec l'éosine, l'amorceur étant PDO + MDEA. La réactivité de ce système est comparée à celle des amorceurs UV pour la polymérisation en film et en solution. Les processus mis en je

ISSN:0003-3146    

DOI:10.1002/apmc.1985.051350105

出版商:Hüthig&Wepf Verlag    

年代:1985

数据来源: WILEY

摘要:

AbstractThe sorption and transport of cyclohexane in poly(ethylene terephthalate) (PETP) fibres with various molecular orientations below the glass transition have been studied. The results have been analyzed in terms of the dual sorption model which has been successfully employed for glassy polymers. It has been shown that the capacity of the Langmuir mode of sorption inherent to glassy polymers is connected with the molecular orientation in the fibres of PETP. The increase of molecular orientation in the fibres has caused the decrease of the Langmuir capacity of PETP. This postulates a decrease in the free volume as a consequence of gradually increasing molecular orientation. Observations on the diffusion coefficients and activation energies for cyclohexane‐PETP fibres system have been discusse

ISSN:0003-3146    

DOI:10.1002/apmc.1985.051350106

出版商:Hüthig&Wepf Verlag    

年代:1985

数据来源: WILEY

摘要:

AbstractExtensional flow behaviour is very important in polymer processing operations such as fiber spinning and film blowing but there is scanty experimental data in the literature due to inherent difficulties in measurement of the relevant flow parameters. In the present paper, an attempt has been made to correlate the existing available data on the extensional flow of three generic types of polymer melts through a logarithmic plot of modified extensional viscosity function, ηE· MFI, and a modified extension rate, (ε/MFI)2. The method may be extended to other polymeric syste

ISSN:0003-3146    

DOI:10.1002/apmc.1985.051350107

出版商:Hüthig&Wepf Verlag    

年代:1985

数据来源: WILEY

摘要:

AbstractThe behaviour of macroporous methacrylate copolymers was investigated in the temperature range between 20 and 270°C. On the basis of retention of methyl alcohol and n‐decane a discontinuity at 40°C was recorded in all cases, interpreted by the increasing mobility of chains of surface layers of the polymer globules. This temperature agrees with the reported Tgvalue of poly(glycidyl methacrylate) and is independent of further substitution of the polymer chain with ionogenic groups. At 210–250°C depolymerization takes place; in the case of methacrylic acid copolymers cyclic anhydrides are formed, while in the case of esters alkyls are eliminated. Modified copolymers of 2,3‐dihydroxypropyl methacrylate with ionogenic groups are more stable thermally — the depolymerization proceeds under the same conditions to a smaller degree. Heating is connected with changes in the morphology of particles and pores, and also in the polarity of the polymers noticeable by the ratio of retentions of alcohols and paraffins and by the heat of d

ISSN:0003-3146    

DOI:10.1002/apmc.1985.051350108

出版商:Hüthig&Wepf Verlag    

年代:1985

数据来源: WILEY

摘要:

AbstractThe use of modern methods of building optimal experimental matrices is especially suitable for optimization of properties of polymeric compound mixtures. We show how, with a limited number of well defined experiments, we optimized rheological properties of a mixture of a lauryl acrylate‐stearyl methacrylate based copolymer and a resinic ester. The methodology is founded upon the determination of coefficients of a mathematical model postulated a priori, describing the property studied in function of variables of composition. This model is then used for forecasting purposes to determine simultaneously the copolymer composition and the ratio of different ingredients to obtain a mixture possessing the expected rheological properties. These mixtures were studied to elaborate a truly polyvalent cross‐country ski

ISSN:0003-3146    

DOI:10.1002/apmc.1985.051350109

出版商:Hüthig&Wepf Verlag    

年代:1985

数据来源: WILEY

摘要:

AbstractIn view of the manufacture of printing plates, films consisting of diethyleneglycol diacrylate and poly(methyl methacrylate) acting as a binding agent were cured by UV‐radiation. 9‐Phenyl acridine was used as the photoinitiator.During polymerization of the diacrylate a highly crosslinked polymer network is formed, having strong inhomogeneities concerning crosslink density. Because of incompatibility between poly(diethyleneglycol diacrylate) and poly(methyl methacrylate) phase separation occurs. However, entanglements of the PMMA chains with the polymer network cause the formation of a semi‐interpenetrating polymer network, thus preventing a two‐phase morphology with a typical domain st

ISSN:0003-3146    

DOI:10.1002/apmc.1985.051350110

出版商:Hüthig&Wepf Verlag    

年代:1985

数据来源: WILEY