New Breathable Films Using a Thermoplastic Cross-Linked Starch as a Porogen

摘要

Breathable films, which find in variety of product applications, are conventionally made using mineral porogens such as calcium carbonate (CaCO_3). This article addresses a novel biodegradable and highly breathable film without inorganic porogens. Unexpectedly, a thermoplastic cross-linked natural polymer (corn starch) was used successfully to create tortuous passages for film breathability. This concept was demonstrated using two types of thermoplastic cross-linked corn starches as porogens and contrasted to control samples: native corn and chemically cross-linked starches, respectively. The films discussed had increased breathability and mechanical properties relative to the control samples. The film morphology reveals that filler was irregular when thermoplastic starch or CaCO_3 was used. The difference in filler from chemically modified cross-linked starch and thermoplastic cross-linked starch was observable as well. It is believed that spherical particles provided by thermoplastic cross-linked starch helps film debonding and porosity during the film stretch processes. VC 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41016.