The influence of organic diluents and solvents on the stability of PVC plastisol water dispersions

The influence of organic diluents and solvents on the stability of PVC plastisol water dispersions The work presents the research, the aim of which is to specify the influence of organic diluents and solvents such as xylene, toluene, n-butyl acetate and butanol as well as cyclohexanone on the stability of water dispersions of the PVC plastisol containing various surface-active agents (SAA). The applied surfactants were characterised by a specific ethoxylation number, molecular mass, the Hildebrand parameter, hydrophilic-hydrophobic balance, surface activity, the limiting viscosity number, the Haller interaction constant, the limiting equivalent conductivity and the Kohlrausch-Onsager equation "b" constant. Basing on the molar refraction and the Hildebrand parameter, the interactions between the plastisol constituents and the constituents of water dispersions of the PVC plastisol were established. The sedimentation tests on the PVC plastisol water dispersions stabilized by various surface-active agents with an organic diluent or solvent added indicated that the addition resulted in the dispergation yield, a reduction in the PVC plastisol molecular size in water dispersion and the increased Huggins interaction constant, showing both surface lyophilisation and higher adsorption of surface-active agents.

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EFFECTS OF SOLVENTS AND SURFACE-ACTIVE AGENTS ON PLASTID PHOSPHATIDASE C ACTIVITY

Canadian Journal of Biochemistry and Physiology ◽

10.1139/y57-016 ◽

1957 ◽

Vol 35 (1) ◽

pp. 127-142 ◽

Cited By ~ 4

Author(s):

Morris Kates

Keyword(s):

Ethyl Ether ◽

Butyl Acetate ◽

Cyclic Ethers ◽

Surface Active Agents ◽

Cationic Detergents ◽

Propyl Ketone ◽

Surface Active ◽

Anionic Detergents ◽

High Concentrations ◽

Aliphatic Ethers

Large stimulations of plastid phosphatidase C activity were produced by (i) linear aliphatic ethers, ketones, and esters; (ii) mixtures of methanol with ethyl ether, petroleum ether, or benzene; and (iii) anionic detergents. Cyclic ethers, ketones, or esters and also alcohols, aldehydes, halogenated compounds, or hydrocarbons produced relatively small stimulations; cationic or non-ionic detergents produced little or no stimulation. The stimulations produced by linear aliphatic ethers, ketones, or esters varied greatly with the chain length of the hydrocarbon groups attached to the oxygen functional group: in each respective class, the most effective solvents were ethyl ether, n-propyl ketone, methyl pentyl ketone, ethyl butyrate, and butyl acetate. The most probable mechanism for explaining the stimulation effect is concluded to be one which involves adsorption of the stimulating solvents at the surfaces of the lecithin and plastid particles in a manner which makes these surfaces lipophilic and thus mutually attracting.In general water-insoluble solvents (ethers, ketones, esters, hydrocarbons) produced relatively little inactivation of enzymatic activity, while water-miscible solvents (alcohols, cyclic ethers, etc.) were strongly inactivating, especially at high concentrations (60–70%). Anionic detergents were not inhibitory in the concentration range in which they were stimulating (< 0.02 M), but were inhibitory at higher concentrations; cationic detergents were strongly inhibitory at all concentrations.It is concluded that extraction of plant phosphatides without concomitant enzymatic degradation should be possible by the use of i-propanol or n-propanol as solvent.

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