ABSTRACT

In this work, a miniaturized peel-testing setup capable of performing peel tests for viscoelastic polymer strips attached to rigid substrate at different peel rates (20 nm/s–20 µm/s) and at constant peel angles (45°–135°) was developed. A mathematical framework accounting for competition between the delamination from rigid substrate as well as bending and extension of the peel arm during the peel test was employed for modeling the viscoelastic response of the soft polymeric strips attached to a rigid substrate. The efficacy of the novel miniaturized peel-testing setup was evaluated for linear elastic and viscoelastic peel arms attached to rigid substrates. The adhesion measurements for the linear elastic peel arms were found to be insensitive to peel angles and the values were in great agreement with standardized macroscale adhesion measurements for the same interface. The peel tests revealed that the interfacial adhesion measurements for the viscoelastic PDMS peel arms were highly sensitive to the nominal peel rates. An elaborate specimen fabrication process was developed to evaluate the interfacial adhesion between large area 2D materials and soft polymer substrates. A series of peel-testing experiments were performed to ensure that the developed fabrication process does not adverse effects on the interfacial adhesion measurements. The peel-testing methodology was then employed to quantify the interfacial adhesion between graphene monolayers and PDMS substrates. Due to the weak van der Waals interactions associated with the graphene/PDMS interface, the interfacial adhesion measurements for this interface was significantly lower than the adhesion values for a PDMS/PDMS interface.

摘要

在这项工作中，一种小型化剥离测试装置能够以不同的剥离速率 (20 nm/s–20 µm/s) 和恒定的剥离角度 (45°–135°) 对附着在刚性基材上的粘弹性聚合物条进行剥离测试已开发。在剥离测试期间，考虑到从刚性基底的分层以及剥离臂的弯曲和延伸之间的竞争的数学框架被用于模拟附着在刚性基底上的软聚合物条带的粘弹性响应。对连接到刚性基材的线弹性和粘弹性剥离臂的新型微型剥离测试装置的功效进行了评估。发现线性弹性剥离臂的粘附测量对剥离角度不敏感，并且这些值与同一界面的标准化宏观粘附测量非常一致。剥离测试表明，粘弹性 PDMS 剥离臂的界面粘附测量对标称剥离速率高度敏感。开发了一种精细的样品制造工艺来评估大面积 2D 材料和软聚合物基材之间的界面粘附力。进行了一系列剥离测试实验，以确保开发的制造工艺不会对界面粘附测量产生不利影响。然后采用剥离测试方法来量化石墨烯单层和 PDMS 基材之间的界面粘合力。