Electrospun Multilayered Films Based on Poly(3-hydroxybutyrate-co-3-hydroxyvalerate), Copolyamide 1010/1014, and Electrosprayed Nanostructured Silica

In this research, bio-based electrospun multilayered films for food packaging applications with good barrier properties and close to superhydrophobic behavior were developed. For this purpose, two different biopolymers, a low-melting point and fully bio-based synthetic aliphatic copolyamide 1010/1014 (PA1010/1014) and the microbially synthesized poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and food-contact-complying organomodified silica (SiO2) nanostructured microparticles, were processed by electrospinning. The production of the multilayer structure was finally obtained by means of a thermal post-treatment, with the aim to laminate all of the components by virtue of the so-called interfiber coalescence process. The so developed fully electrospun films were characterized according to their morphology, their permeance to water vapor and oxygen, the mechanical properties, and their water contact angle properties. Interestingly, the annealed electrospun copolyamide did not show the expected improved barrier behavior as a monolayer. However, when it was built into a multilayer form, the whole assembly exhibited a good barrier, an improved mechanical performance compared to pure PHBV, an apparent water contact angle of ca. 146 degrees, and a sliding angle of 8 degrees. Consequently, these new biopolymer-based multilayer films could be a bio-based alternative to be potentially considered in more environmentally friendly food packaging strategies.

Automated summary

In this research, bio-based electrospun multilayered films with good barrier properties and superhydrophobic behavior were developed for food packaging applications. Two different biopolymers, a synthetic aliphatic copolyamide and a microbially synthesized poly(3-hydroxybutyrate-co-3-hydroxyvalerate), were processed by electrospinning and layered with organomodified silica nanostructured microparticles. The resulting films exhibited improved barrier and mechanical properties, high water contact angle, and low sliding angle. These biopolymer-based multilayer films could be a promising environmentally friendly alternative for food packaging.