Understanding Architecture Hierarchy of Polymer Networks to Control Mechanical Responses

在材料研究部聚合物项目的支持下，阿拉巴马大学伯明翰分校(UAB)的研究团队正在开发具有微调结构和精确控制物理性能的聚合物网络，如机械行为以及水凝胶膨胀和表面形态。材料结构对于它们在传感、药物输送和组织工程中的应用至关重要。然而，具有复杂层次结构的纳米硫蛋白水凝胶的制备还有待探索。这项拟议研究的目标将是了解薄纳米结构水凝胶中结构层次对控制水凝胶机械响应的影响。这个项目将为内部网络安排和僵化之间的相互作用带来新的见解，作为一个新颖而有趣的研究领域。这种知识将导致开发出更多样化和更坚固的聚合物结构，能够根据需要进行弹性变化，这将极大地拓宽我们控制生物反应和模拟生物组织的能力。该项目的教育和外联活动将加强妇女和代表不足的群体在本科生和研究生研究中的科学参与。该项目还将旨在通过伯明翰科学中心的知识传播，提高公众对聚合物网络和参与科学的认识。教育和推广工作将使UAB生物医学研究社区认识到对新的聚合物材料的需求，并有助于提高美国在该领域的经济竞争力。本项目将探索薄型水凝胶涂层的内部结构和结构等级调节的刚性。涂层将通过聚合物在表面的顺序吸附以多层水凝胶的形式获得。将致力于以下目标：(A)了解非牺牲聚合物的相对分子质量对多层水凝胶分层和力学性能的影响；(B)研究多层交联对水凝胶分层和力学性能的影响；以及(C)了解聚合物链疏水性对多层水凝胶分层的影响。这项拟议的研究的主要基本意义将是对纳米结构多层网络与其刺激响应和机械性能之间的结构-性能关系获得新的见解。这项研究将影响一种新型聚合物水凝胶的发展，并将提供对这些材料的物理化学性质的基本了解。拟议研究的具体影响将是：(I)开发具有受控内部结构层次的新型共聚物和新型平面水凝胶，(Ii)产生关于结构层次对分层水凝胶的尺寸变化和力学响应的影响的新知识，以及(Iii)为开发水凝胶结构作为受控药物输送和微流体环境中的刚性定向传输的自变形材料开辟新的前景。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

With the support of the Polymers program in the Division of Materials Research, the University at Alabama-Birmingham (UAB) research team is developing polymeric networks with finely tuned architectures and precisely controlled physical properties, such as mechanical behavior along with hydrogel swelling and surface morphology. Materials architecture would be essential for their applications in sensing, drug delivery, and tissue engineering. However, the preparation of nanothin hydrogels with complex hierarchical structures has yet to be explored. The goal of the proposed study will be to understand the effects of architecture hierarchy in thin nanostructured hydrogels for controlling hydrogel mechanical responses. This project will bring new insights into the interplay between internal network arrangement and rigidity as a novel and intriguing research area. This knowledge will result in the development of more diverse and robust polymeric structures capable of elastic change on demand, which would vastly broaden our capabilities to control biological responses and mimic biological tissues. The educational and outreach activities of this project will enhance science participation of women and underrepresented groups in undergraduate and graduate research. The project will also aim to increase public awareness of polymer networks and engagement with science through knowledge dissemination at the Birmingham Science Center. The education and outreach efforts will provide awareness of UAB biomedical research community toward a need for new polymer-based materials and contribute to the economic competitiveness of the USA in this field. This project will explore the internal architecture- and architecture hierarchy-regulated rigidity of thin hydrogel coatings. The coatings will be obtained as multilayer hydrogels using sequential adsorption of polymers at surfaces. The following aims will be pursued: (a) understanding the effect of molecular weight of a non-sacrificial polymer on multilayer hydrogel stratification and mechanical properties; (b) investigating the effect of multilayer crosslinking on hydrogel stratification and mechanical properties; and (c) understanding the role of polymer chain hydrophobicity on multilayer hydrogel stratification. The main fundamental significance of the proposed study will be in obtaining new insights into the structure-property relationships between nanostructured multilayer networks and their stimuli-responsive and mechanical properties. This research will impact the development of a new type of polymer hydrogel with architecture hierarchy-regulated rigidity and will provide a fundamental understanding of the physicochemical properties of these materials. The specific impact of the proposed study will be in (i) developing novel copolymers and new types of planar hydrogels with controlled internal architecture hierarchy, (ii) generating new knowledge on the effect of architecture hierarchy on dimensional changes and mechanical responses of the stratified hydrogels; and (iii) opening new prospects for developing hydrogel structures as self-transformable materials for controlled drug delivery, and in rigidity-directed transport in microfluidic environments.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.