Torlon AI-10 polymer solutions

In Fig. 12.21, the solution viscosity is illustrated for Torlon AI-10 dissolved in NMP at various percent solids and measured at different temperatures. NMP is most commonly used due to its high solvency power, its low odor, and a relatively low level of toxicity. Diluents maybe added up to the level provided in Table 12.2 to lower viscosity and formulation cost. 

Alternatively, Torlon AI-10 powder may be formulated using a mixed organic aqueous system, where water is the major solvent component, as shown in Table 12.3 [26]. AI-10 is approximately 50% imidized along the polymer backbone. The remaining amic acid groups can form hydrophUic ammonium complexes, allowing a high portion of water in the formulation. 

Alternatively, TbrlonAI-30 and AI-50 are amenable to aqueous systems when formulated with a tertiary amine Table 12.4 [27]. Due to the very low degree of imidization compared to AI-10 or polyamide-imides produced in the isocyanate process, these polymers can form stable, low-viscosity solutions in water at low to moderate polymer sohds. Generally the polymer sohds are 5 to 15%, depending on the polyamide-imide used, and provide solutions with a viscosity in the range of 50 to 2000 cP. 

By using standard injection-molding equipment and the right set points, polyamide-imide molding resins may be routinely processed. A short 

TABLE 12.3 Torlon AI-10 in Mixed Organic Aqueous System 

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