No abstract

SynopsisVapor phase photografting of monomer mixtures on low-density polyethylene film, on which benzoyl peroxide is coated, was investigated at 60°C using various vinyl, allyl, and solid monomers. Styrene (St) itself was difficult to graft on the film substrate, but the combinations of St with vinyl monomers such as acrylonitrile (AN), glycidyl methacrylate (GMA), acrylic acid, and methacrylic acid led to the accelerated grafting, affording a maximum percent grafting at an certain monomer ratio. The same combination effect was observed for AN-N-vinyl pyrrolidone and -GMA monomer mixtures. The monomer combinations such as allyl aldehyde-St and allyl alcohol-maleic anhydride were useful for performing the grafting of allyl monomers effectively. Maleic anhydride and maleimide as solid monomers were also possible to introduce into the film substrate by means of the monomer combination, where St, N-vinyl pyrrolidone, vinyl ethers, and benzyl methacrylate were available as comonomers. Thus, the monomer combinations affording an accelerating effect on grafting may be monomer pairs rich in an alternative copolymerizability, suggesting that monomer reactivity ratio controls a major factor for the combination effect. It was confirmed from IR study on grafted films that both monomer components are introduced in the film substrate as the grafted chain component.

Cellulosic materials (DP, SCP) and PVA fibers were treated with four kinds of metallic ions (Ca2+, Fe2+, Fe3+, Ce4+), and the adsorption behavior was studied to elucidate the manner in which the celluloses and the metallic ions were combined. The effects of treatment temperature, time, and concentration upon the amount of the metallic ions adsorbed were examined. With Ca2+ and Fe2+, the effects of such factors on the adsorption were slight, while with Fe3+ and Ce4+ the effects of time, temperature, and ion concentration were pronounced. Also, it was evident that the amount (molar) of equilibrium adsorption of Ca2+ or Fe2+ was approximately the same as the content of carboxyl groups in the cellulose sample, and the amount of equilibrium adsorption of Fe3+ or Ce4+ was approximately the same as that of total carbonyl group content. When the samples which had adsorbed these metallic ions were treated with 0.1N hydrochloric acid, the Ca2+ and Fe2+ were completely desorbed while about 80% of the adsorbed Fe3+ and Ce4+ remained. These results indicate that there are two types of combinations of cellulosic materials and metallic ions involved: one is thought to be an ionic bond, while the other is considered to be a chelate bond.

synopsisThe widths at half-value of high-resolution NMR spectra of bound water of cellulose were studied in relation to the temperature change. Two points were made clear: First, the amount of bound water of the cellulose sample can be pointed out with higher accuracy the lower the temperature of the measurement. Second, it is possible to determine in a simple manner the boundary temperature T, at which water molecules become bound by the cellulose. T, is characteristic of the cellulose sample of a given water content and corresponds to the glass transition temperature of the water-containing sample. The measurements appear to be readily applicable to other hydrophilic polymers.