| 摘要 |
Peelable heat-seal film is a coestrudate with a polycarbonate or a nylon substrate of a blend contg. a polybutylene (PB) with melt index 9.1-500 (pref. 1-4) selected from butent-1 homopolymers or copolymers with ethylene or propylene, with either (a) poly-propylene (PP) and modified EVA copolymer (M-EVA); or (b) a tie layer adhesive comprising modified low density polyethylene (M-LDPE); or (c) PP and M-LDPE. With polycarbonate, peel strength is 0.3-9 (pref. 1.0-8) lb./in at sealing jaw temp. 230-330 (pref. 280-320) def.F; proportions of components in the blends are (all wt.%) 9-25 (pref. 10-20) PB with (a) 2-15 (pref. 3-10) PP and 60-92 (pref. 70-87) M-EVA; or (b) 75-92 (pref. 80-90) M-LDPE; or (c) 2-15 (pref. 3-10) PP and 60-90 (pref. 5-37) M-LDPE. With nylon proportions are 6-25 (pref. 8-20) PB with (a) 2-15 (pref. 3-10) PP and 60-92 (pref. 70-89) M-EVA: or (b) 75-94 (pref. 80-92) M-LDPE; or (c) 3-15 (pref. 3-10) PP and 60-91 (pref. 70-80) H-LDPE; and corresp. peel strengths at jaw temps. 520-410 (pref. 350-400) deg.F are respectively (a) 0.4-5 (pref. 1.0-3.2); (b) 1.5-5 (pref. 1.8-3. 2): and (c) 0.4-5 (pref. 1.8-3.2).
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