Abstract

Needs for biodegradable packaging materials are growing to reduce the negative environmental impact of petroleum-based polymer packaging. Barrier paper packaging is in demand as environmentally-friendly barrier coating materials to improve biodegradability and recyclability. Cellulose nanofibril (CNF) is considered an alternative to conventional polymers for barrier coatings due to the barrier properties of its films. In this work, various types of CNFs were prepared and coated on linerboard and wood-free paper to evaluate the barrier properties of these papers against air, liquid water, water vapor, oxygen, and grease, and the major factors of the barrier performance of the CNFs-based coatings were investigated. A coat weight of at least 10 g/m² was desirable to impart efficient the barrier properties to papers. The average fibril size and hydrophobicity were strongly related to the barrier properties. CNFs with smaller fibril sizes are beneficial for enhancing barrier properties, and hydrophobization improves the water resistance. Hydrophobic functional groups with sufficient chain lengths decreased the water vapor barrier properties. The average fibril diameter of CNFs may be related to the air resistance, oxygen barrier properties, and grease resistance.

Graphic abstract

摘要

为了减少石油基聚合物包装对环境的负面影响，对可生物降解包装材料的需求正在增长。要求使用防潮纸包装作为环境友好的防潮涂料，以提高生物降解性和可回收性。纤维素纳米原纤维（CNF）由于其薄膜的阻隔性能而被认为是传统聚合物的替代品，用于阻隔涂层。在这项工作中，制备了各种类型的CNF，并将其涂布在挂面纸板和无木材纸上，以评估这些纸对空气，液态水，水蒸气，氧气和油脂的阻隔性能，以及影响其阻隔性能的主要因素。研究了基于CNFs的涂料。涂层重量至少为10 g / m ²期望有效地赋予纸阻隔性。平均原纤维尺寸和疏水性与阻隔性能密切相关。具有较小原纤维尺寸的CNF有助于增强阻隔性能，疏水化可改善耐水性。具有足够链长的疏水性官能团降低了水蒸气阻隔性能。CNF的平均原纤维直径可能与空气阻力，氧气阻隔性能和耐油脂性有关。

图形摘要