Collaborative Research: Interfacial Phenomena of Functional Solutes Impregnated into Cellulose Packaging Substrates

包装对日常生活至关重要。它保护我们的食品和药品，促进全国和世界各地货物的安全运输。基于塑料的包装已经变得流行，因为它提供了比传统纸基包装更好的阻隔性能，这有助于保持包装产品的质量和安全性。尽管塑料包装有很多好处，但其不良的报废特性和回收挑战往往会导致环境污染。该研究项目旨在开发一种可持续和功能性的纸基替代品，以替代塑料包装，可以使用可再生原料和绿色化学技术制造。从农业废弃物中提取的生物基化合物将被浸渍到纸中，以改善材料的功能和阻隔性能。将研究纸张和生物基化合物之间的分子水平相互作用，以开发具有竞争力和可持续性的塑料包装替代品。为了增加STEM领域的多样性并促进经济繁荣，该项目将吸引来自传统上在STEM领域代表性不足的背景和群体的高中生，本科生和研究生。此外，外展活动将提高公众对可持续包装实践的认识。该项目由界面工程计划和刺激竞争研究的既定计划（EPSCoR）共同资助。该研究旨在开发下一代可持续包装材料，具有良好的性能和寿命终止特性，通过工程纤维素基材具有更好的阻隔性能。这将使用超临界浸渍（SCI）方法来实现，其中超临界二氧化碳（ssCO 2）用于将生物衍生的溶质吸附到纤维素基质中。溶质吸附到纤维素纤维的基本界面现象将被确定。两个模型溶质系统-脂肪族和芳香族-和共溶剂已被选择来代表来自农业残留物的化学物种。预期脂肪族溶质系统产生包装材料所需的疏水性质，并且预期芳香族溶质系统赋予UV吸收性质。将使用最先进的石英晶体微天平（QCM-D）仪器测量溶质在纤维素纤维上的初始吸附动力学，并建模以量化影响速率常数的工艺条件的影响。在操作近红外（NIR）光谱研究将阐明基本的键合和分区过程，促进SCI的纸基材，包括氢键的界面纤维素纤维，氢键的影响scCO 2-助溶剂的相互作用，和scCO 2-助溶剂-纤维素的相互作用对溶质分配到纤维素的影响。最后，溶质扩散机制和整个纤维素基质中溶质的最终分布之间的关系将通过数字成像分析进行评估，通过接触角和透光率测量分别评估两个系统的功能改善。这项研究以多种方式为社会做出贡献，包括开发可持续的包装材料，提高生物衍生溶质作为包装添加剂的潜力，为代表性不足的学生提供研究机会，该奖项反映了NSF的法定使命，并已被认为是值得通过评估使用基金会的智力价值和更广泛的支持。影响审查标准。

Packaging is essential to everyday life. It protects our food and medicine and facilitates the safe transport of goods across the country and around the world. Plastics-based packaging has become popular because it offers better barrier properties than traditional paper-based packaging, which helps preserve the quality and safety of packaged products. Despite the benefits of plastic packaging, the poor end-of-life characteristics and recycling challenges often lead to environmental pollution. This research project seeks to develop a sustainable and functional paper-based alternative to plastic packaging that can be manufactured using renewable feedstocks and green chemistry technologies. Bio-based compounds extracted from agricultural waste will be impregnated into paper to improve the material’s functionality and barrier properties. The molecular-level interactions between paper and bio-based compounds will be examined to develop a competitive and sustainable alternative to plastic packaging. To increase diversity in STEM fields and promote economic prosperity, this project will engage high school, undergraduate, and graduate students from backgrounds and groups traditionally underrepresented in STEM fields. Additionally, outreach events will enhance public awareness of sustainable packaging practices.This project is jointly funded by the Interfacial Engineering program and the Established Program to Stimulate Competitive Research (EPSCoR). The research aims to develop next-generation sustainable packaging materials, with favorable performance and end-of-life characteristics, by engineering cellulosic substrates with improved barrier properties. This will be accomplished using the supercritical impregnation (SCI) methodology, where supercritical carbon dioxide (ssCO2) is used to impregnate bioderived solutes into cellulose matrices. The fundamental interfacial phenomena governing solute adsorption onto the cellulosic fibers will be determined. Two model solute systems – aliphatic and aromatic - and cosolvents have been chosen to represent the chemical species derived from agricultural residues. The aliphatic solute system is expected to yield desirable hydrophobic properties for the packaging material, and the aromatic solute system is expected to impart UV-absorbent properties. The initial adsorption kinetics of the solutes onto the cellulosic fibers will be measured using state-of-the-art quartz crystal microbalance (QCM-D) instrumentation and modeled to quantify the impact of the process conditions influencing rate constants. In operando near-infrared (NIR) spectroscopic studies will elucidate fundamental bonding and partitioning processes that facilitate SCI of paper substrates, including the hydrogen-bonding of interfacing cellulosic fibers, the influence of scCO2-cosolvent interactions on hydrogen-bonding, and the impact of scCO2-cosolvent-cellulose interactions on solute partitioning into cellulose. Lastly, relationships between solute diffusion mechanisms and the resultant distribution of solutes throughout cellulosic matrices will be evaluated via digital imaging analyses, with functional improvements assessed via contact angle and light transmittance measurements for the two systems, respectively. This research contributes to society in multiple ways, including developing sustainable packaging materials, advancing the potential of bioderived solutes as packaging additives, providing research opportunities for underrepresented students, and educating the community on sustainable packaging benefits through outreach events.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.