Isobutylene-butene copolymers identified in paragraph (a) of this section may be safely used as components of articles intended for use in contact with food, subject to the provisions of this section.
Isobutylene-butene copolymers | Molecular weight (range) | Viscosity (range) | Maximum bromine value |
1. Used as release agents in petroleum wax complying with § 178.3710 of this chapter | 300 to 5,000 | 40 to 20,000 seconds Saybolt at 200 °F | 40 |
2. Used as plasticizers in polyethylene or polypropylene complying with § 177.1520 , and in polystyrene complying with § 177.1640 | 300 to 5,000 | 40 to 20,000 seconds Saybolt at 200 °F | 40 |
3. Used as components of nonfood articles complying with §§ 175.300 , 176.170 , 176.210 , 177.2260(d)(2) , 177.2800 , and 178.3570 (provided that addition to food does not exceed 10 parts per million), or § 176.180 of this chapter | 300 to 5,000 | 40 to 20,000 seconds Saybolt at 200 °F | 40 |
4. Used as production aids in the manufacture of expanded (foamed) polystyrene articles complying with § 177.1640 of this chapter | 150 to 5,000 | Less than 20,000 seconds Saybolt at 200 °F | 90. |
5. Used in release coatings on backings or linings for pressure-sensitive adhesive labels complying with § 175.125 of this chapter | 150 to 5,000 | Less than 20,000 seconds Saybolt at 200 °F | 90 |
21 C.F.R. §177.1430