Polymers high nitrile, barrier properties

Copolymers of acrylonitrile [107-13-1] are used in extmsion and molding appHcations. Commercially important comonomers for barrier appHcations include styrene and methyl acrylate. As the comonomer content is increased, the permeabiUties increase as shown in Figure 3. These copolymers are not moisture-sensitive. Table 7 contains descriptions of three high nitrile barrier polymers. Barex and Cycopac resins are mbber-modified to improve the mechanical properties. 

In Region IV, performance again increases. Crystallographic transformations in phosphate conversion coatings at 180 C are known to adversely affect phosphate crystal adhesion (26). However, nitrile cyclization may be important at these higHer temperatures. Cyclization is believed to enhance barrier properties of high nitrile polymers (27,28.29). 

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