高阻隔耐热PET/PEN饮料瓶的研制

用双螺杆挤出机研究了熔融挤出工艺、原料的选择及配比对聚对苯二甲酸乙二酯(PET)/聚对萘二甲酸乙二酯(PEN)共混物耐热性和阻隔性的影响,并利用差示扫描量热仪、核磁共振仪进行了性能表征。结果表明,PET与PET-PEN共聚酯容易熔融共混,即在无定形态相容;随挤出时间和温度的增加,PET/PEN共混物的冷结晶温度升高、熔点降低、阻隔性降低而玻璃化转变温度不变;随PET-PEN含量的增加,共混物的阻隔性和耐热性得到改善。用注-拉-吹工艺成型可得到PET/PEN共混物饮料瓶,其耐热性和对氧气的阻隔性比纯PET瓶高,且随PET-PEN含量的增加而提高。

DEVELOPMENT OF HIGH OBSTRUCTHING AND HEAT-RESISTANT PET/PEN BEVERAGE BOTTLE

The effects of reactive blending process,material selecting and proportioning on the obstructing and heat-resistance of PET-PEN blends were studied by means of twin-screw extruder.DSC and NMR were used to characterized the blends.The results showed that PET and PET-PEN copolymer could be mixed easily,which meaned PET and PET-PEN copolymer were miscible in amorphous phase.With increasing of extrusion time and temperature,the cold crystallization temperature increased,the melting temperature and obstructing decreased,but the glass transition temperature didn't change.The heat resistance and obstructing of blends increased with the PET-PEN copolymer content increasing.PET/PEN blend bottle was obtained with the injection-extension-blow molding process.The barrier property to oxygen and heat-resistance of the bottle were improved obviously by comparison with pure PET bottle.