Improving the oxygen and water vapour barrier properties of PLA via a novel interface engineering

In this work, we adopt “hyperthermal hydrogen-induced cross-linking (HHIC) technology” to fix an interfacial control layer of polyacrylic acid (PAA) on polylactic acid (PLA) to improve the adhesion and integrity of the permeation barrier film, and meanwhile, the HHIC treatment causes no measurable damage to the functional groups of PAA and PLA. Consequently, the oxygen transmission rate decreases from 150.00 to 0.50 ml m −2 day −1 (a reduction of 99.7%), which is less than one tenth of the best value reported, and that the water vapour transmission rate decreases from 32.93 to 16.25 g m −2 day −1 (a reduction of 50.7%), which is slightly higher than the best value reported (3.8% higher). Our work shows that the HHIC technology used in this study provides an efficient way to improve the oxygen and water vapour blocking ability of PLA and may help in improving the quality of other polymer heterointerfaces in the future.