申请人:Mitsui Chemicals, Inc.
公开号:US05998039A1
公开(公告)日:1999-12-07
Disclosed is a polypropylene composition comprising (A) polypropylene and (B) a specific propylene-1-butene random copolymer in a specific amount ratio. The propylene-1-butene random copolymer (B) is characterized in that: (1) the copolymer contains 50 to 95% by mol of constituent units from propylene and 50 to 5% by mol of constituent units from 1-butene, (2) the intrinsic viscosity, as measured in decahydronaphthalene at 135.degree. C., is in the range of 0.1 to 12 dl/g, (3) the molecular weight distribution (Mw/Mn), as determined measured by GPC, is not more than 3, and (4) the parameter B value indicating randomness of the copolymerized monomer sequence distribution is in the range of 1.0 to 1.5. Also disclosed is a polypropylene composite film comprising (I) a crystalline polypropylene layer and (II) a layer formed from the polypropylene composition, which is laminated on at least one surface of the crystalline polypropylene layer (I). The polypropylene composition is excellent in heat resistance and low-temperature heat-sealing properties as well as in flexibility and impact resistance. The polypropylene composite film is excellent in not only heat-sealing properties, particularly low-temperature heat-sealing properties, but also transparency, scratch resistance and blocking resistance.
本发明公开了一种聚丙烯组合物,包括(A)聚丙烯和(B)一种特定比例的丙烯-1-丁烯随机共聚物。丙烯-1-丁烯随机共聚物(B)的特点在于:(1)共聚物含有50至95摩尔%的丙烯组分单元和50至5摩尔%的1-丁烯组分单元,(2)在135℃下以脱氢萘为测量溶剂时的固有粘度在0.1至12 dl/g范围内,(3)分子量分布(Mw/Mn)由GPC测量确定,不超过3,(4)表示共聚单体序列分布随机性的参数B值在1.0至1.5范围内。本发明还公开了一种聚丙烯复合膜,包括(I)晶体聚丙烯层和(II)由聚丙烯组合物形成的层,该层层压在晶体聚丙烯层(I)的至少一表面上。聚丙烯组合物在耐热性、低温热封性、柔韧性和抗冲击性方面均表现出色。聚丙烯复合膜在热封性能,特别是低温热封性能、透明度、耐刮擦性和防粘性方面均表现出色。