TY - JOUR
T1 - Tailored polyethylene nanocomposite sealants
T2 - Broad-range peelable heat-seals through designed filler/polymer interfaces
AU - Zhang, Jinguo
AU - Manias, Evangelos
AU - Polizos, George
AU - Huh, Jin Young
AU - Ophir, Amos
AU - Songtipya, Ponusa
AU - Del Mar Jimenez-Gasco, Maria
N1 - Funding Information:
Financial support and generous donations of materials by Kraft Global Foods are gratefully acknowledged. Additional financial support by the National Science Foundation (Grant No. DMR-0602877, an MWN/Polymer Division grant) was provided to G. P. and E. M., and by the Penn State University Agricultural Experimental Station to P. S. and M. M. J. G.
PY - 2009
Y1 - 2009
N2 - The heat sealing behavior of novel polyethylene-based nanocomposite films was investigated, as they relate to flexible packaging of fresh-cut vegetables, processed foods and biomedical devices. Appropriately designed sealant nanocomposites, which include dispersed montmorillonite nanofillers and ethyl vinyl acetate copolymer, produce a hermetic but peelable heat seal across a broad, 30-40°C, range of heat sealing temperatures, outperforming optimized commercial polyethylene-based sealants that achieve peelable seals in a much narrower heat sealing temperature range, of less than 15°C. Appropriate nanocomposite design leads to a general easy-open/peelable character of heat seals, which is: (a) independent of sealing conditions and apparatus - ranging from long dwell times at very high sealing pressures to very short heat impulses at very low sealing pressures; (b) markedly independent of the opposite side of the heat seal - for example, when sealed on itself, on unfilled sealant, or on high density polyethylene; and (c) rather insensitive to formulation variations of the sealant - for example, variations of the polyethylene of the ethyl vinyl acetate type and concentration, and of nanofiller loading. Insights from observations of the fracture seal surfaces by infrared spectroscopy and electron microscopy reveal that the underlying mechanism of this behavior is related to a synergistic effect of the ethyl vinyl acetate copolymer and the montmorillonite clay nanofiller, which introduces weak interfaces in the nanocomposite that lead to cohesive failure of the sealant.
AB - The heat sealing behavior of novel polyethylene-based nanocomposite films was investigated, as they relate to flexible packaging of fresh-cut vegetables, processed foods and biomedical devices. Appropriately designed sealant nanocomposites, which include dispersed montmorillonite nanofillers and ethyl vinyl acetate copolymer, produce a hermetic but peelable heat seal across a broad, 30-40°C, range of heat sealing temperatures, outperforming optimized commercial polyethylene-based sealants that achieve peelable seals in a much narrower heat sealing temperature range, of less than 15°C. Appropriate nanocomposite design leads to a general easy-open/peelable character of heat seals, which is: (a) independent of sealing conditions and apparatus - ranging from long dwell times at very high sealing pressures to very short heat impulses at very low sealing pressures; (b) markedly independent of the opposite side of the heat seal - for example, when sealed on itself, on unfilled sealant, or on high density polyethylene; and (c) rather insensitive to formulation variations of the sealant - for example, variations of the polyethylene of the ethyl vinyl acetate type and concentration, and of nanofiller loading. Insights from observations of the fracture seal surfaces by infrared spectroscopy and electron microscopy reveal that the underlying mechanism of this behavior is related to a synergistic effect of the ethyl vinyl acetate copolymer and the montmorillonite clay nanofiller, which introduces weak interfaces in the nanocomposite that lead to cohesive failure of the sealant.
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U2 - 10.1163/156856108X379182
DO - 10.1163/156856108X379182
M3 - Article
AN - SCOPUS:66749176643
SN - 0169-4243
VL - 23
SP - 709
EP - 737
JO - Journal of Adhesion Science and Technology
JF - Journal of Adhesion Science and Technology
IS - 5
ER -