Nanoparticle interactions with swollen polymer networks

水凝胶是一种柔软的聚合物网络，可以吸收大量的水，使其对分子具有高度的渗透性--类似于液态水，但具有类似固体的机械性能。它们被广泛用于家庭和工业应用，包括食品、化妆品、医药、农业和提高石油采收率。虽然水凝胶的性能通常是通过聚合物化学来针对特定的应用而定制的，但另一种方法是使用纳米颗粒来改变其微观结构，从而形成“水凝胶纳米复合材料”。其动机可能是降低成本，特别是对于大规模工业应用，或者为利基应用实现非常特定的特性。然而，纳米颗粒掺杂带来了过多的新的实际和基础性科学挑战。这些问题是由于纳米颗粒与交联型聚合物网络相互作用的复杂和鲜为人知的方式造成的。拟议的研究将使用理论、计算和实验方法来解决几个基本的科学挑战，这些方法将有助于解决在水凝胶技术中使用纳米颗粒所产生的重要工业和社会问题。设想的是一个以电声、介电和流变光谱为特色的“诊断工具箱”，以及一个明确量化纳米颗粒与水凝胶网络相互作用的纳米颗粒分析。在未来五年内，将通过集成(I)实验模型系统，(Ii)弹性声学、介电和流变学的新应用，(Iii)连续尺度计算和(Iv)分子尺度模拟，来寻求在先进材料、环境和人类健康领域开发和应用该平台所需的力学见解。这项研究计划将产生基础知识，以加强加拿大的先进材料和生物技术产业，在纳米颗粒释放、运输和人类健康问题上提供严格的科学投入，并为新一代工程师提供专业知识和实用专业知识，以领导工业和学术。

Hydrogels are soft polymer networks that take on striking amounts of water, making them highly porous to moleculessimilarly to liquid waterbut with solid-like mechanical properties. They are used in a vast range of domestic and industrial applications, including food, cosmetics, medicine, agriculture, and enhanced oil recovery. While hydrogel properties are often tailored to specific applications via polymer chemistry, another approach is to modify the microstructure using nanoparticles, thus forming ``hydrogel nano-composites''. The motivation may be to reduce costs, particularly for large-scale industrial applications, or to achieve very specific properties for niche applications. However, nanoparticle doping brings with it a plethora of new practical and fundamental scientific challenges. These arise from the complicated and poorly understood manner in which nanoparticles interact with cross-linked polymer networks. The proposed research will tackle several fundamental scientific challengesusing theoretical, computational, and experimental methodologiesthat will help to address important industrial and societal questions arising from nanoparticle use in hydrogel technologies. Envisioned is a ``diagnostic toolbox''featuring electroacoustic, dielectric and rheological spectroscopyand a nanoparticle assay to unambiguously quantify how nanoparticles interact with hydrogel networks. The mechanistic insights required to develop and apply this platformin advanced-materials, environmental, and human-health fieldswill be sought in the next five years by integrating (i) experimental model systems, (ii) novel applications of elactro-acoustic, dielectric and rheological spectroscopy, (iii) continuum-scale computation, and (iv) molecular-scale simulation. This program of research will generate fundamental knowledge to strengthen Canada's advanced materials and bio-technology industries, provide rigorous scientific input on nanoparticle release, transport and human-health concerns, and empower a new generation of engineers with expert knowledge and practical expertise for industrial and academic leadership.