Styrene-acrylonitrile staining

Fig. 4. TEM micrograph of a craze tip in poly(styrene-acrylonitrile) (stained with 0s0.t). The film is tilted so the craze front (normal to the film surface) can be seen in projection. Note the stained wedge of plastically deformed polymer ahead of the crtize tip. Courtesy of Dr. A. M. Donald...

ABS comprises the dispersed phase of styrene/acrylonitrile copolymer grafted on polybutadiene rubber and the continuous phase of styrene/acry-lonitrile copolymer. The use of SAN grafted on polybutadiene rubber provides high impact strength, processability, chemical resistance, staining property, etc., as the characteristics peculiar to ABS resins. 

Diarylamiaes fuactioa as mbber antioxidants by breaking the peroxidative chain reactions leading to mbber deterioration. Nearly all commercial synthetic mbbers (see Elastomers, synthetic), including neoprene, butyl, styrene—butadiene, and the acrylonitrile—butadiene mbbers, can be protected with about 1—2% of an alkylated diphenylamine. DPA itself is not used as a mbber antioxidant. An objectionable feature of these antioxidants is that they cause discoloration and staining which limits their use to applications where this is not important. 

Exterior durability is enhanced by inclusion of methacrylates and acrylates. Styrene, methacrylic acid, and acrylic acid increase hardness in the coating, while flexibility is conferred by ethyl, butyl, or ethyl-hexyl acrylate. Stain resistance is improved when short-chain (meth)-acrylates are used and acrylics also impart improved resistance to waten Solvent and grease resistance can be improved by copolymerizing acrylonitrile, methacrylamide, and methacrylic acid. 

Figure 10 shows a 3D surface-rendered image of an ultrathick specimen of an acrylonitrile butadiene styrene (ABS) resin. The ABS resin (TECNO ABS 330) was purchased from Technopolymer Co. Ltd., Japan. The thickness of the micro-tomed section is ca. 1pm. The spatial distribution of 0s04-stained polybutadiene (PB) spherical domains (often... 

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