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POLYMERIC SURFACE ACTIVE AGENT

Long-chain alcohols, such as are obtained by the hydrogenation of coconut oil, polymerization of ethylene, or the 0x0 process (qv), are sulfated on a large scale with sulfur thoxide or chlorosulfuhc acid to acid sulfates the alkaU salts are commercially important as surface-active agents (see Surfactants). Poly(vinyl alcohol) can be sulfated in pyhdine with chlorosulfuhc acid to the hydrogen sulfate (84). [Pg.200]

However, emulsion polymerizations involve the formation of colloidal polymer particles that are essentially permanently suspended in the reaction medium. The reaction mechanism involves the migration of monomer molecules from liquid monomer droplets to sites of polymerization that originate in micelles consisting of surface-active agent molecules surrounding monomer molecules. Emulsion polymerizations are usually characterized by the requirement of surfactants during the initiation of the process and by the use of water-soluble initiators. This process also permits good control of the exothermic nature of the polymerization. [Pg.30]

Nonionic Surface-Active Agents. Approximately 14% of the ethylene oxide consumed in the United States is used in the manufacture of nonionic surfactants. These are derived by addition of ethylene oxide to fatty alcohols, alkylphenols (qv), tall oil, alkyl mercaptans, and various polyols such as polypropylene glycol), sorbitol, mannitol, and cellulose. They are used in household detergent formulations, industrial surfactant applications, in emulsion polymerization, textiles, paper manufacturing and recycling, and for many other applications (281). [Pg.466]

Okamura, S., K. Katagiri and Y. Takemoto Effect of surface-active agents in the polymerization of acrylonitrile. J. Chem. Soc. Japan, Ind. Chem. Sect. 61, 241-243 (1958). [Pg.440]

The rubber particle size in the final product increases several fold if the prepolymerization is carried out in the presence of a dilute aqueous solution of an alkane sulfonate or polyvinyl alcohol in place of pure water. The addition of a surface-active agent converts the coarsely dispersed oil-water mixture—obtained as above in the presence of pure water—into an oil-in-water emulsion. In this case even prolonged stirring during prepolymerization does not decrease the rubber particle size appreciably in the final product. The stabilization of the droplets of the organic phase in water by the emulsifier obviously impedes or prevents agitation within the polymeric phase. Figure 1 shows the influence of these three prepolymerization methods (under otherwise equal reaction conditions) on the dispersion of rubber particles in polystyrene. [Pg.233]

The highly effective surface active agent, Decon 90, which is claimed to be suitable for virtually all laboratory cleaning applications. It is totally rinsable, phosphate free, biodegradable and non-toxic. It is particularly suitable for silicone oils, greases, polymeric residues and tars. [Pg.28]

Until the last few decades colloid science stood more or less on its own as an almost entirely descriptive subject which did not appear to fit within the general framework of physics and chemistry. The use of materials of doubtful composition, which put considerable strain on the questions of reproducibility and interpretation, was partly responsible for this state of affairs. Nowadays, the tendency is to work whenever possible with well-defined systems (e.g. monodispersed dispersions, pure surface-active agents, well-defined polymeric material) which act as models, both in their own right and for real life systems under consideration. Despite the large number of variables which are often involved, research of this nature coupled with advances in the understanding of the fundamental principles of physics and chemistry has made it possible to formulate coherent, if not always comprehensive, theories relating to many of the aspects of colloidal behaviour. Since it is important that colloid science be understood at both descriptive and theoretical levels, the study of this subject can range widely from relatively simple descriptive material to extremely complex theory. [Pg.2]

The polymerizations are generally carried out in bulk or in solution (THF, di-oxane, toluene, etc.). The dispersion polymerization of e-CL using a mixture of 1,4-dioxane and heptane and surface-active agents yields a polymer in the form of microspheres with a narrow molecular weight distribution [63]. [Pg.11]

Emulsion polymerization is one of the major processes for the production of industrial polymers. It represents a sizable application for surface active agents, although manufacturers tend to minimize their use because of economic and environmental considerations (surfactants are usually more expensive compared to monomers and are mostly left in the liquor) and because of the negative effects on the final properties of the polymers and of their coalesced films. [Pg.221]

Polymeric fibers are popular for reinforcing concrete matrices because of their low density (more number of fibers for a prescribed volume fraction), high tensile strength, ease of dispersion, relative resistance to chemicals, and relatively low cost compared to other kinds of fibers. Polypropylene and polyolefin fibers are typically hydrophobic, resulting in a relatively poor bond with concrete matrices compared to some other types of fibers. Treatment of polypropylene with an aqueous dispersion of colloidal alumina or silica and chlorinated polypropylene enhances the affinity of these fibers toward cement particles. Treatment of polypropylene fibers with a surface-active agent provides better dispersion of the fibers and a stronger bond between cement and fiber. The earlier attempts at surface treatments of polypropylene fibers have had only limited success and have not been commercially attractive. [Pg.648]

Thiazetidine 1,1-dioxides or 3-sultams can be polymerized to high-molecular-weight polysulfonamides.l,2-Thiazetidin-3-one 1,1-dioxides react with aliphatic diamines to give polyamide-poly sulfonamide polymers. Fluorinated 3-keto and 3-imino derivatives were investigated as surface-active agents, and Ai-malonyl derivatives of l,2-thiazetidin-3-one 1,1-dioxide are said to be yellow couplers for color photography. ... [Pg.592]

The USPNF 23 describes methacrylic acid copolymer as a fully polymerized copolymer of methacrylic acid and an acrylic or methacrylic ester. Three types of copolymers, namely Type A, Type B, and Type C, are defined in the monograph. They vary in their methacrylic acid content and solution viscosity. Type C may contain suitable surface-active agents. Two additional polymers, Type A (Eudragit RE) and Type B (Eudragit RS), also referred to as ammonio methacrylate copolymers, consisting of fully polymerized copolymers of acrylic and methacrylic acid esters with a low content of quaternary ammonium groups, are also described in the USPNF 23. A further monograph for an aqueous dispersion of Type C methacrylic acid copolymer is also defined see Section 9. [Pg.553]

Use Polymerization modifier, insecticide intermediate, vulcanization accelerator intermediate, nonionic surface-active agent. [Pg.704]


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Activating agents

Activator polymerization

Agents, polymeric

Polymeric surfaces

Polymeric surfaces surface

Polymerization activity

Polymerization agents

Polymerization surface activation

Polymerization, activation

Surface polymerization

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