摘要:
The invention relates to blown films and methods of making blown films using a melt-strength enhanced polyester composition. The composition has a zero-shear viscosity and a degree of shear thinning that are comparable to PVC's melt rheology. The polyester composition has a branching agent and/or a fluoropolymer processing additive and an inherent viscosity of at least 0.60 dl/g. The diacid component of the polyester composition comprises 97 to 100 mole percent of residues of terephthalic acid, naphthalenedicarboxylic acid, isophthalic acid or mixtures thereof. The glycol component of the polyester composition comprises 97 to 100 mole percent of residues of ethylene glycol, 1,4-cyclohexanedimethanol, diethylene glycol, neopentyl glycol or mixtures thereof.
摘要:
Disclosed are polyester blends useful for the preparation of heat-shrinkable films, and heat-shrinkable films prepared therefrom. The heat shrinkable film may be oriented in the machine direction to produce films with high machine-direction shrinkage but low transverse growth or shrinkage. The films are useful for roll-fed, shrink-on label applications. Also disclosed are heat-shrinkable roll-fed labels prepared from reactor-grade polyesters.
摘要:
An ultraviolet absorption composition has been developed for the protection of packaging or container contents in the ultraviolet range of 290 nm to 390 nm, offering effective screening from all wavelengths of solar radiation. A combination of an optical brightener with an ultraviolet absorber has been found to provide effective screening without adding significant color to the polymer composition. This extended range of ultraviolet blocking over what can be achieved with ultraviolet absorbers alone is especially valuable in food and drink packaging applications where the contents of the packages need ultraviolet protection to prevent discoloration or development of undesirable flavors.
摘要:
Disclosed are void-containing polyester shrink films which show excellent density retention upon exposures to high temperatures. The films have high shrinkage and retain their low density after processing under conditions of temperature and moisture used in typical recycling processes. The films are useful for sleeve label and other shrink film applications, and their lower density allows them to be readily separated from soft drink bottles, food containers and the like during recycling operations. Also disclosed is a process for void-containing polyester shrink films having high shrinkage and low density after exposure to elevated temperatures.
摘要:
Disclosed are void-containing polyester shrink films which show excellent density retention upon exposures to high temperatures. The films have high shrinkage and retain their low density after processing under conditions of temperature and moisture used in typical recycling processes. The films are useful for sleeve label and other shrink film applications, and their lower density allows them to be readily separated from soft drink bottles, food containers and the like during recycling operations. Also disclosed is a process for void-containing polyester shrink films having high shrinkage and low density after exposure to elevated temperatures.
摘要:
A reactor grade copolyester composition, as well as a heat-shrinkable film made therefrom, unexpectedly has higher ductility than a multi-component blend of copolyesters with the same monomer concentrations. The reactor grade copolyester composition is made from a diacid component of at least about 90 mole percent and a diol component of (a) about 72 to about 88 mole percent ethylene glycol, about 10 to about 15 mole percent 1,4-cyclohexanedimethanol, and about 2 to about 13 mole percent diethylene glycol, or (b) about 59 to about 77.5 mole percent ethylene glycol, about 15 to about 28 mole percent 1,4-cyclohexane-dimethanol, and about 7.5 to about 13 mole percent diethylene glycol. Further, the heat-shrinkable film may be produced to closely match the shrink characteristics of polyvinyl chloride by varying the amounts of the diol components of the reactor grade copolyester composition. Furthermore, a reactor grade copolyester composition has a b* color value of −1.0 to less than 4.5, wherein the diacid component is at least about 90 mole percent terephthalic acid and the diol component is about 52 to about 88 mole percent ethylene glycol, about 10 to about 28 mole percent 1,4-cyclohexane-dimethanol, and about 2 to about 20 mole percent diethylene glycol.