ISSN:0449-2994    

DOI:10.1002/polc.5070370113

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

年代:1972

数据来源: WILEY

摘要:

AbstractSynthesis of cellulose graft copolymers with mixtures of N‐vinyllactams (VL) and vinyl monomers (VM), the definition of the copolymer composition of the grafted chain, coefficients of relative monomers reactiveness, solubility, characteristic viscosity, and the effect of the initial monomer ratio on the obtained products properties are reported.N‐vinylpirrolidone, N‐vinylcaprolactam, and methylmethacrylate butylmethacrylate, acrylonitrile, and β‐hydroxyacrylate glycidic ether were used in the investigations as well as preparations of cotton fibers, fibers of diacetylcellulose, and fibers of viscose staple rayon.VL and VM were grafted onto cellulose in the oxidative‐reductive systems of bivalent ferrous and hydrogen peroxide at various molar ratio (0.1:0.9; 0.25:0.75; 0.5:0.5; 0.75:0.25; 0.9:0.1). The VL‐VM copolymer side chains were hydrolytically isolated from the grafted part of cellulose. The values of rVLand rVMwere plotted as those of rVLand rVMfor the static polymerization. It is found that the composition of the grafted cellulose side chains was identical with that of the copolymers, which have been obtained by the bulk method. The copolymers solubility remained the same after the grafted cellulose chain was isolated by the classic method of copolymerization in the absence of cellulose.The graft copolymers were identified by IR spectra. The mechanism of the graft copolymerization is given for all the abovementioned monomers a

ISSN:0449-2994    

DOI:10.1002/polc.5070370114

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

年代:1972

数据来源: WILEY

摘要:

AbstractThe grafting on rayon fiber of acrylic and methacrylic monomers was studied through the decomposition of the hydroperoxide and peroxide groups, created in a process of ozonization. The graft copolymers was characterized by chemical analysis, infrared spectroscopy, and thermo‐oxidative decompositio

ISSN:0449-2994    

DOI:10.1002/polc.5070370115

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

年代:1972

数据来源: WILEY

摘要:

AbstractAt first polyvinyl alcohol was used as a model for cellulose, and the grafting of styrene and methyl methacrylate was carried out in a heterogeneous system by use of mutual irradiation, preirradiation, and catalytic method. In all cases trichloroethylene or carbon tetrachloride was added to the reaction mixture to shorten the branches. True graft copolymers were isolated by vigorous alternate extraction of unreacted PVAL and homo‐PST (or‐PMMA), and hydroxyl groups in the copolymers were completely acetylated to carry out osmotic measurements. Molecular weights of the separated chains and the mother polymers were also determined by osmometry. It was shown that the graft copolymer has only one mother PVAL molecule and one graft branch regardless of the grafting methods employed. In the case of cellulose, high tenacity rayon was used as a substrate. The reaction product was acetylated, and the extraction of homo‐PST and unreacted cellulose (in the form of triacetate) was carried out with benzene (at 80°C) and CH2Cl2‐MeOH (1:1, at room temp.), respectively. In this case also, it was shown that the graft copolymer molecule consisted of one graft branch and one mother cellulose

ISSN:0449-2994    

DOI:10.1002/polc.5070370116

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

年代:1972

数据来源: WILEY

摘要:

AbstractThe structure of cotton fibers grafted by radiation induced polymerization with butyl methacrylate and acrylonitrile was investigated by light and electron microscopy. Degree and uniformity of dye uptake was used to indicate uniformity of reaction. The internal structure of the fibers was studied with the transmission electron microscope using ultrathin cross sections and solubility tests. Changes in the fiber surface, and types of damage caused by abrasion were evaluated with the scanning electron microscope. These tests indicated that the grafting procedure had changed the surface as well as the internal fibrillar character of the fibers and the extent of such changes increased with increasing content of graft polymer.

ISSN:0449-2994    

DOI:10.1002/polc.5070370117

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

年代:1972

数据来源: WILEY

摘要:

AbstractThe potential of radiation copolymerized celluloses in chromatography, particularly in the reversedphase technique is discussed. A range of styrenated celluloses has been prepared from copolymerizing styrene with Whatman 40, 41, and 42 papers. The effect of percent styrene on the separation characteristics of a number of dyestuffs on these grafted papers has been studied. Significant differences in chromatographic behavior of the dyes is observed between the grafted and nongrafted papers. Similar changes in RFvalues between the two types of papers are also observed for the separation of a range of 19 typical cations. Detailed studies have been performed particularly with Zn+2, NI+2and Cd+2. In the separation of the fatty acids, stearic, myristic and lauric, the grafted celluloses are shown to possess advantages over the untreated Whatman equivalent. For column chromatography, a methylmethacrylate‐cellulose radiation copolymer has been used to quantitatively separate a mixture of oil soluble dyes. This same mixture could not be separated on a column of untreated cellulose powder. Finally the ion exchange properties of grafted copolymers where the monomer contains a functional group such as −NH2, −SO3H or even a heterocyclic nitrogen (the vinyl pyridines) are disc

ISSN:0449-2994    

DOI:10.1002/polc.5070370118

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

年代:1972

数据来源: WILEY

摘要:

AbstractWood pulp cellulose was grafted with styrene and a number of other vinyl monomers using the mutual radiation technique. The effects of the level of grafting, type of monomer, and the grafting conditions on the water sorption equilibria and kinetics were determined. Styrene was studied in considerable detail. Styrene grafting reduced the equilibrium water content but water diffusivities increased as a consequence of styrene grafting. Conversely, the grafting of polar monomers such as acrylonitrile, ethyl acrylate, and acrylic acid led to somewhat higher water regains but to decreased diffusion constants.The swelling conditions used during the mutual grafting process with styrene significantly affected the grafting rates and the properties of the resulting grafts. For example, the equilibrium water contents at the same level of grafting, was a function not only of percent graft but also of the specific swelling conditions. These moisture regains were inversely related to the density of the grafted fibers. These results are discussed in terms of the conformation of the grafted side chains which is determined by the various grafting conditions.

ISSN:0449-2994    

DOI:10.1002/polc.5070370119

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

年代:1972

数据来源: WILEY

摘要:

AbstractIn this work we tried to explain the thermal behavior of grafted celluloses. Using the thermogravimetric method with constant heating rate, we came to the following important conclusions concerning the thermal stability and the mechanism destruction: the thermal stability of cellulosic derivatives decreases comparatively with the cellulosic material used; the degradation mechanism is very complex occurring by concurrent reactions depending on the nature of the nature of the initial cellulosic support and the degree of substitution.

ISSN:0449-2994    

DOI:10.1002/polc.5070370120

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

年代:1972

数据来源: WILEY

ISSN:0449-2994    

DOI:10.1002/polc.5070370121

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

年代:1972

数据来源: WILEY

摘要:

AbstractCotton cellulose graft copolymers and terpolymers were prepared by radiation initiated processes. Monomers copolymerized with irradiated cellulose from solutions of methanol‐water were: methacrylic acid (MAA), methacrylonitrile (MAN), and hexafluoroisopropyl acrylate (6FIPA). Cotton cellulose, immersed in solutions of N‐vinyl carbazole (NVC) in 1,2‐dichloroethane, was irradiated to form a copolymer. Terpolymers prepared were; cellulose‐poly(MAA)‐poly(MAN), cellulose‐poly(MAA)‐poly(6FIPA), and cellulose‐poly(MAN)‐poly(6FIPA). Textile properties of the cotton fabric copolymers and terpolymers determined included: flex and flat abrasion resistance, breaking strength, and water repellency. The properties of the cellulose copolymers and terpolymers were related to chemical structures of the monomers used and the glass transition temperatures of t

ISSN:0449-2994    

DOI:10.1002/polc.5070370122

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

年代:1972

数据来源: WILEY