PEELABLE-SEAL POLYOLEFIN COMPOSITION AND SEALANT LAYER

摘要

The present invention relates to an olefin sealant composition and sealant layer having easy-open heat seal characteristics. The novel composition and sealant layer are made from at least one ethylene polymer, at least 25 weight percent (based on the total weight of the composition or layer) of at least one polybutylene polymer, a silica-containing or calcium-containing additive, a slip additive and optional quantities of an ethylene polymer as additive carrier resin. The preferred ethylene polymer is a homogeneously branched ethylene polymer and the preferred polybutylene polymer has a low crystallinity or high comonomer content. As a sealant layer, the composition has excellent hot tack properties, relative low coefficient of friction and especially exceptional sealing properties wherein its heat seal strength is in the range of from 1.5 to 3.5 1bs./inch (0.27 to 0.64 kg/cm) width at 100 DEG C and the statistical average deviation of its heat seal strength between 100 DEG C to 130 DEG C sealing temperatures is less than or equal to 16.5 percent. The composition is useful in applications that require consistent and stable peelable seal performance across broad sealing windows such as, for example, cereal box liners.