Erucamide-free closure and liner compositions
View Patent ↗An exemplary erucamide-free composition for making container closures or closure sealants includes a matrix polymer, a silicone lubricant such as poly(dimethyl)siloxane, and a slip aid comprising a saturated amide, oxidized polyethylene, or combination thereof.
1. A closure for a food or beverage container, wherein the closure includes a sealant liner molded from a composition comprising
(A) a polymer component, which is essentially free of erucamide and other unsaturated amide, said polymer component comprising a thermoplastic polymer selected from the group consisting of polyethylene, ethylene copolymer with other lower alkenes, polypropylene, thermoplastic rubber, poly(ethylene propylene) copolymer, acid modified ethylene propylene copolymer, styrene butadiene rubber, carboxylated styrene butadiene block co-polymer, polyisoprene, styrene isoprene styrene block copolymer, styrene butadiene styrene block copolymer, styrene ethylene butylene styrene block copolymer, polystyrene block polyethylene/propylene copolymer, ethylene vinyl acetate copolymer or terpolmer, ethylene acrylate copolymer or terpolymer, ethylene vinyl alcohol copolymer, butyl rubber, poly(vinyl chloride) polymer, and mixtures thereof;
(B) a lubricant comprising an organopolysiloxane, said organopolysiloxane having an average molecular weight not less than 40,000, said organosiloxane being present in an amount not less than 0.01 parts and not greater than 10 parts based on 100 parts of said polymer component (A), and said organopolysiloxane having a viscosity of at least 50,000 cst; and
(C) a slip aid comprising a saturated amide and an oxidized polyethylene, said slip aid being present in an amount not less than 0.01 parts and not greater than 8 parts based on 100 parts of said polymer component (A), said amide having an iodine value no greater than 5 in accordance with ASTM D2075-92.
2. A closure according to claim 1 , wherein said saturated amide is selected from the group consisting of behenamide, stearamide, arachidamide, palmitamide, myristamide, lauramide and ethylene bis-stearamide.
3. A closure according to claim 2 , wherein said polymer component comprises an ethylene vinyl acetate copolymer in an amount not less than 5 parts and not greater than 100 parts, based on 100 parts of said polymer component (A).
4. A closure according to claim 2 , wherein said polymer component comprises polyethylene, polypropylene, or a mixture thereof.
5. A closure according to claim 2 , wherein said polymer component comprises a copolymer of polyethylene and polypropylene.
6. A closure according to claim 2 , wherein said polymer component comprises ethylene vinyl acetate copolymer and poly(ethylene propylene) copolymer.
7. A closure according to claim 2 , wherein said polymer component comprises poly(vinyl chloride) polymer.
8. A closure according to claim 2 , wherein said polymer component comprises polyethylene, polypropylene, or a mixture thereof; and further comprises styrene-ethylene butylene-styrene block copolymer.
9. A closure according to claim 1 , wherein said saturated amide is behenamide.
10. A closure according to claim 9 , wherein said organopolysiloxane is poly(dimethyl)siloxane.
11. A closure according to claim 1 , wherein said organopolysiloxane is poly(dimethyl)siloxane.
12. A closure according to claim 1 , wherein said saturated amide is stearamide.
13. A closure according to claim 12 , wherein said organopolysiloxane is poly(dimethyl)siloxane.