生物材料於澱粉系防油紙塗層之應用

Abstract

人們為降低環境污染及資源浪費，環境友善材料逐漸受到重視。紙質材料不僅擁有良好的機械性能，其輕巧且環保的先天優勢使其具有取代傳統塑膠包裝的潛力，然而，紙包裝材料的多孔結構及親水性官能基使其在應用上受到諸多限制，為了改善其防油性、防水性及氣體阻隔性，表面塗布被視為有效的解決方法之一。 為因應綠色化學之發展趨勢，本研究配製不同濃度（10 wt%、15 wt%、20 wt%）的辛烯基琥珀酸酐澱粉（OSA starch）塗料（OS10、OS15、OS20），塗布於紙張表面後測定其防油性及防水性，探討最佳的塗布濃度。接著，與不同比例的生物材料，微晶纖維素（MCC）、纖維素奈米結晶（CNC）、纖維素奈米纖維（CNF）、奈米高嶺土（NCK）及奈米木質素顆粒（LNPs），與OSA澱粉（最佳濃度）混合並配製成塗料（基於OSA澱粉之1 wt%、3 wt%、5 wt%），塗布於紙張表面後測定其防油性、防水性、機械性能及白度，探討最佳的塗布配方。結果顯示，較低濃度的塗料難以均勻塗布於紙張表面，OS10及OS15表現出較差的防油性及防水性，而OS20表現出較佳的防油性及防水性，因此，本研究將OSA澱粉塗料的濃度設定為20 wt%，與上述的生物材料混合後進行後續實驗。後續實驗結果顯示，纖維素材料的粒徑對於塗布紙的防油性及防水性並無顯著的影響，對於機械性能的影響較為顯著。此外，相較於OSA澱粉塗布紙，CNF、CNC及LNPs的添加皆可提升塗布紙的防油性及機械性能，但過量添加會對塗布紙的防水性及機械性能造成負面影響，其中，CNF3表現出最佳的防水性及防油性，上膠度增加了18.07%，抗油度由9提升至10，顯示此配方具有應用於防油紙塗層並做為食品包裝材料的潛力。

To reduce environmental pollution and resource waste, environmentally friendly materials have gained international attention. Paper-based materials not only possess good mechanical properties but also have the inherent advantages of being lightweight and environmentally friendly, making them potential alternatives to traditional plastic packaging. However, the porous structure and hydrophilic functional groups of paper packaging materials pose various limitations in their applications. Surface coating is considered an effective solution to improve their grease resistance, water resistance, and gas barrier properties. To meet the trend of green chemistry development, this study prepared octenyl succinic anhydride starch ( OSA starch ) coatings at different concentrations ( 10, 15, 20 wt% ) and applied them to the paper surfaces to evaluate their grease resistance and water resistance, aiming to determine the optimal coating concentration. Subsequently, various proportions of bio-based materials, microcrystalline cellulose ( MCC ), cellulose nanocrystals ( CNC ), cellulose nanofibers ( CNF ), lignin nanoparticles ( LNPs ), and nanoclay kaolinite ( NCK ), were mixed with the optimized concentration of OSA starch coating to develop the composite coatings ( 1, 3, and 5 wt% based on the dried weight of OSA starch ), which were then applied to paper surfaces to evaluate their grease resistance, water resistance, mechanical properties, and optical properties, aiming to determine the optimal coating formulation. The results showed that lower concentrations of coatings are hard to uniformly apply to the paper surface, with OS10 and OS15 exhibiting poor grease resistance and water resistance. OS20 demonstrated better grease resistance and water resistance, thus the concentration of OSA starch coatings was set at 20 wt%. The subsequent experiments showed that the particle size of cellulose materials has no significant impact on the grease resistance and water resistance of coated paper but has a more notable effect on the mechanical properties. Furthermore, compared to the paper coated with OSA starch coating, the addition of CNF, CNC, and LNPs improves the grease resistance and mechanical properties of coated paper, but excessive addition has a negative impact on water resistance and mechanical properties. Among them, CNF3 exhibits the best water resistance and grease resistance, with an increase in sizing degree of 18.07%, and an increase in grease resistance from 9 to 10, demonstrating the potential of this formulation for application as a greaseproof paper coating and food packaging material.