Temporary plasticizers

The volatile content of the treated paper is important because moisture acts as a temporary plasticizer to promote resin flow during early stages of pressing (9). Dynamic mechanical analysis of the treated paper is a very useful means to study the initial flow stages of a resin and the cure time required to complete cross-linking (10). 

There are several techniques for producing polymer mixtures for further processing into articles by the reactive (chemical) molding methods simultaneous formation of two polymeric systems with mutual entanglement of their chains and the appearance of so-called interpenetrating networks synthesis of the second polymer within an expanded network of the initial polymer incorporation of oligomers into a polymer matrix as a temporary plasticizer followed by polymerization. 

Coalescing agents are, in reality, temporary plasticizers, which promote the coalescence by increasing the amount of plastic flow in latex paints. The types of materials used are ether-alcohol (such as butyl glycol), tributyl phosphate, pine oil, or other strong solvents. All of these have a degree of volatility so that within a period of time they are lost from the film so that the latex hardens to its required properties. 

The Tg of bulk ethylcellulose is in the range of 129-133 C, and therefore at ambient conditions films of ethylcellulose are substantially brittle. To be used in film coating applications, ethylcellulose requires the addition of pla.sticizer to improve film flexibility and toughness. The Tg of dried latex particles of Aquacoat ECD has been reported to be 89 C (7). The reduced Tg of ethylcellulose particles dried from a pseudolatex is the result of the temporary plasticizing effects of water. Although the Tg of ethylcellulose... 

Butyl diglycol acetate [124-17-4] [2-(2-butoxyethoxy)ethyl acetate] is a high boiler that is used as a temporary plasticizer, as a leveling agent in stoving enamels and in printing inks, as a film-forming auxiliary in acrylate copolymer dispersions, and to reduce the viscosity of poly(vinyl chloride) plastisols. 

Virtually all end-use formulations of latex polymers of MFT much above 5 °C (40 °F) contain a moderately low volatility solvent for the polymer. These act as temporary plasticizers to ensure low MFT and enhance polymer interdiffusion. The solvent should diffuse and evaporate as quickly as possible for film hardness development, but not at the expense of completeness of film strength development A complication is that compositions of high Tg which contain solvent... 

Verreck, G. Decorte, A. Heymans, K. Adriaensen, J. Cleeren, D. Jacobs, A. Liu, D. et al. The effect of pressurized carbon dioxide as a temporary plasticizer and foaming agent on the hot stage extrusion process and extrudate properties of solid dispersions of itraconazole with PVP-VA 64. Eur. J. Pharm. Sci. 2005, 26(3-4), 349-358. 

Volatile Liquids. These are chilled and mixed into the liquid polymer system at room temperature. They provide temporary plasticization. Then, the heat of processing volatilizes them, plasticization ceases, and the expanding gas bubbles produce the foam. 

A similar technique can be employed when dry-spinning PHB from solution. In fact there is somewhat greater latitude in the drawing conditions for this process since the spherulitic morphology of solution-cast PHB is much finer and intrinsically more ductile than that of melt-cast polymer. Moreover, residual solvent in the thread line can act as a temporary plasticizer to aid the drawing process. 

Mostly act as temporary plasticizers, but residual solvent control may be needed... 

Solvents, primarily for solvent adhesives, but sometimes also added to emulsions in small quantities as temporary plasticizers, are mainly petroleum, toluene, xylene, dichloromethane, trichloroethylene, trichloroethane, ethyl acetate, acetone, 2-butanone,... 

Coalescent Coalescing Agent) n Solvent with a high bp which, when added to a coating, aids in film formation via temporary plasticization (softening) of the vehicle. 

A number of factors control successful film formation. The polymer must be soft enough and have a sufficiently low glass transition temperature (Tg) to allow fusion. For this reason, many of the latex polymers are copolymers, which are usually softer than homopolymers. Coalescing agents are added as temporary plasticizers. As the water evaporates, they have an increasing softening effect on the polymer particles, helping them to coalesce more easily. 

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