Cryptic Hydrogels

非技术摘要水凝胶是一类可随水膨胀的材料，它们在研究和商业中代表着越来越重要的材料类别。它们被用作生物材料、隐形眼镜、吸收材料、伤口愈合材料、保水助剂、涂料、粘合剂和许多其他应用。然而，与工业中通常使用的许多其他类型的塑料材料不同，这些水凝胶通常非常弱，目前还没有强大的机制来按需加强材料。将这一属性构建到这些水凝胶系统中将大大增强它们在现实世界中的应用。总而言之，这一过程花费了10到100亿美元，每种药物需要7到20年的时间。该项目将创造一种通过向凝胶施加力来加强凝胶的方法，具体应用于更好、更坚固的粘合剂。他们还将利用这笔资金为学生创造新的教育机会。具体地说，高中生女性将在夏季被带到实验室，在那里她们可以使用这些和其他复杂的材料和不同的研究人员。技术摘要水凝胶和有机凝胶网络是由可溶性单体前体形成的膨胀的、不溶于水的聚合物网络，在研究和商业应用中是一类越来越重要的材料。它们在学术界和工业界的应用都是深远的，如生物材料和伤口愈合材料；受控输送材料和网络；隐形眼镜；涂层和粘合剂。凝胶的一个关键限制是，与工业热塑性聚合物相比，它们不能因机械变形而增强。在凝胶系统中构建按需硬化可以极大地扩大其在应用中的全部潜力和用途，如稳定和机械坚固的粘合剂、涂层、制成品和潜在的生物材料。在这个项目中，一个由三个实验室组成的团队将1)创建并表征具有应变诱导硬化特性的聚乙二醇凝胶，包括不可逆和静电(可逆)交联，2)将屏蔽基团加入网络以调整其力敏感性，以及3)将这项技术应用于机械活化胶粘剂。这些研究将建立分子和环境参数与应变触发的弹性模数变化与一种新材料类别之间的基本关系。这项工作将为通过应变触发硬化或软化机制控制水凝胶性能提供科学依据。这一贡献意义重大，因为这一基础知识的最终应用可能适用于新的亲水性材料的材料设计以及再生医学和疾病。这项提案中的外展目标将继续PIS在之前由NSF资助的更广泛的影响中开发的当前努力，以扩大为高中女孩量身定做的工程研究机会。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。

Non-Technical AbstractHydrogels are a class of material that can become swollen with water, and they represent an increasingly important category of materials in research and commerce. They are employed as biomaterials, contact lenses, absorbent materials, wound healing materials, water retention aids, coatings, adhesives, and many other applications. However, unlike many other type of plastic materials typically used in industry, these hydrogels are typically very weak, and there is currently no robust mechanism to strengthen the materials on-demand. Building this attribute into these hydrogel systems would significantly enhance their real-world applications. In sum, this process costs one to ten billion dollars, and seven to twenty years per drug. This project will create a way to strengthen gels by applying force to them, with specific applications toward better, more robust adhesives. They will also use this funding to create new educational opportunities for students. Specifically, high school women will be brought into the lab during the summer months, where they can work with these and other sophisticated materials and diverse researchers. Technical AbstractHydrogel and organogel networks are swollen, insoluble polymer networks made from soluble monomer precursors, and they are an increasingly important class of materials in research and commercial applications. Their uses are far-reaching in both academia and industry, as biomaterials and wound healing materials; controlled delivery materials and networks; contact lenses; coatings; and adhesives. One critical limitation for gels has been that, in comparison to industrial thermoplastic polymers, they cannot be strengthened in response to mechanical deformation. Building on-demand stiffening into gel systems could greatly broaden their full potential and utility in applications as stable and mechanically robust adhesives, coatings, fabricated articles, and potentially biomaterials. In this project, a team of three laboratories will 1) Create and characterize poly(ethylene glycol) (PEG) gels with strain-induced stiffening properties, both irreversible and electrostatic (reversible) crosslinks, 2) Incorporate shielding groups into the networks to tune their force sensitivity, and 3) apply this technology to mechanically-activated adhesives. These studies will establish fundamental relationships between molecular and environmental parameters and strain-triggered elastic modulus changes with a new class of materials. This work will provide the scientific foundation for hydrogel property control via strain-triggered stiffening or softening mechanisms. This contribution is significant because the eventual applications of this fundamental knowledge could apply to materials design for new hydrophilic materials as well as regenerative medicine and disease. Outreach objectives in this proposal will continue current efforts developed by the PIs in previous NSF-funded broader impacts in expanding engineering research opportunities tailored for high school girls.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.