Green and scalable processing of water‐soluble, biodegradable polymer/clay barrier films

Poly(vinyl alcohol) (PVOH) based water-soluble packaging with intentional disposal into wastewater provides great convenience for both households and industry. In this paper, we demonstrate CO2 evolution testing that only insignificant fractions (~2%) of PVOH biodegrade in within 33 days. To avoid unintentional environmental build-up the accompanying consequences to marine life, alternative materials a suitable balance performance biodegradability are needed. Until now, barrier properties biodegradable biopolymers could not compete state-of-the-art like films. report on waterborne, sandwich-structured films using hydroxypropyl methylcellulose or alginate produced an industrially scalable slot-die coater system. The inner layer film consists collapsed nematic suspension high aspect ratio synthetic clay nanosheets act as impermeable wall. Such structure allows filler loadings capable sufficiently reducing oxygen water vapor permeability 0.063 cm3 mm m−2 day−1 bar−1 53.8 g bar−1, respectively, but also mechanical reinforcement biopolymer facilitating processing. Moreover, disintegrated less than 6 min while rapid biodegradation dissolved polymer was observed.