Olefin stain

Olefin fibers, also called polyolefin fibers, are defined as manufactured fibers in which the fiber-forming substance is a synthetic polymer of at least 85 wt % ethylene, propjiene, or other olefin units (1). Several olefin polymers are capable of forming fibers, but only polypropylene [9003-07-0] (PP) and, to a much lesser extent, polyethylene [9002-88-4] (PE) are of practical importance. Olefin polymers are hydrophobic and resistant to most solvents. These properties impart resistance to staining, but cause the polymers to be essentially undyeable in an unmodified form. 

Physical Properties. Table 1 (2) shows that olefin fibers differ from other synthetic fibers in two important respects (/) olefin fibers have very low moisture absorption and thus excellent stain resistance and almost equal wet and dry properties, and (2) the low density of olefin fibers allows a much lighter weight product at a specified size or coverage. Thus one kilogram of polypropylene fiber can produce a fabric, carpet, etc, with much more fiber per unit area than a kilogram of most other fibers. 

Used industrially as an oxidizing agent especially in conversion of olefins to glycols, and in the preparation of chlorates, peroxides, and periodates as a biological stain for adipose... 

Miscellaneous. Aside from the oxidation chemistry described, only a few catalytic applications are reported, including hydrogenation of olefins (114,115), a, [3-unsaturated carbonyl compounds (116), and carbon monoxide (117) and the water gas shift reaction (118). This is so owing to the kinetic inertness of osmium complexes. A 1% by weight osmium tetroxide solution is used as a biological stain, particulady for preparation of samples for electron microscopy. In the presence of pyridine or other heterocyclic amines it is used as a selective reagent for single-stranded or open-form B-DNA (119) (see Nucleic acids). Osmium tetroxide has also been used as an indicator for unsaturated fats in animal tissue. Osmium tetroxide has seen limited if controversial use in the treatment of arthritis (120,121). 

The [2 + 2] reaction also occurs for stained olefins 49 and 50, giving only the exo cycloadducts (Scheme 25). It was thought that the reaction proceeds via the exo metallacyclopentane intermediate Y arising from monodentate coordination to the exo face of the bicyclic olefins. The similarity in the electronic spectra of nickel complexes of these olefins to those of the complex of norbomene, which was known to coordinate on the exo face, supports this mechanism. 

Thus, ESCA becomes another powerful mean to estimate the composition of our block copolymer series in the outermost surface area of the membranes. To get the definite ESCA spectral characteristics with these block copolymer membranes, the technique of the reaction of OsO at unsaturated moiety was employed. OsO has been used as a fixative and stain for electron microscopy to biological samples, and as a specific reagent in organic chemistry for the cis-hydroxylation of olefinic double bonds. Firstly, to check the qualitative and quantitative reaction of OsO with double bonds of PB component in the membranes, infrared spectra of these sample membranes were measured. 

The answer to this important question came when a transmission electron microscope (TEM) was applied to stained ultrathin slices of injection molded LDPE/PET samples with an MEC structure [52,55,56]. The results for two cases of the polycondensate/poly-olefin type of MFCs are shown in Figure 11.9. 

Surfactant affinity for the skin was inversely proportional to the amount of dye staining the skin. The data from this study showed that lauryl sulfate and lauryl benzyl sulfate exhibited a greater affinity for the skin than ot-olefin sulfonate and lauryl(3EO)-sulfate. Later, Imokawa et al. [68] showed an apparent correlation between skin roughness and the adsorption of anionic surfactants to isolated stratum comeum. 

The demand for white and coloured mbber articles for various applications is steadily growing. Rubbers are, depending on their content of olefinic double bonds, very sensitive to ozone, and hence effective antiozonants are necessary. Due to their discolouring and staining effect, para-phenylenediamine antiozonants cannot be used in compounds for white or coloured articles. A survey of the effectiveness of Vulkazon AFS, a cyclic acetal providing excellent ozone protection in coloured compounds based on various elastomers, is presented. The effectiveness of the cyclic acetal is compared with paraphenylenediamine antiozonants in chloroprene, butyl and halobutyl compounds. The effect in diene rubbers, where the cyclic acetal has to be used in combination with waxes, is investigated. Cyclic acetals do not affect the peroxide cure like other antiozonants and hence the material has also been tested in peroxide-cured cable jacket compounds based on a saturated elastomer. 2 refs. 

The key to these reactions was the higher rate of reactivity of the cis-olefin relative to the double bonds in the polymer. The predominantly tram stereochemistry of the polymer and the allylic substituents slow the reaction of the polymer double bonds relative to those in the cis acyclic olefin. In subsequent reactions, it was found that the cis-olefin could be present from the hymning of the reaction, that is, the stained norbomene reacted much faster than the cis-olefin. Since the complex resulting from the termination of the polymers with the acyclic... 

The only rule is that you should use durable fabric for outdoor pillows. 1 suggest cotton canvas, duck cloth, vinyl, olefin, or use a shower curtain (Hint Make sure your fillings are 100 percent waterproof too.) 1 like to make pillows out of blankets or bedspreads that have suffered a stain that I can cut out or sew around. 

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