Researcher(s)
- Nat Nagy, Mechanical Engineering, University of Delaware
Faculty Mentor(s)
- Sourav Paul, Mechanical Engineering, University of Delaware
Abstract
Contact angle goniometry is a fundamental technique used to estimate the surface free energy of materials. It is a widely used method for characterizing wettability and is highly relevant to the ongoing research at the Polymer Interfacial Mechanics (PIM) Lab. The lab is conducting experiments regarding the properties of polymers. Of these properties, surface energy is particularly important because it can provide insight into the surface chemistry of polymers. A wide range of commercial systems are available, offering different analysis modes, levels of precision, and software integration. In addition to basic functionality, the PIM lab will need to modify the goniometer to incorporate additional systems, such as testing rigs and specialized stages. However, many of these systems are proprietary and cannot be modified easily or in a way that would comply with usage policies. Additionally, the cost of these instruments often exceeds $5,000, which may be an inefficient use of resources if the lab intends to perform extensive modifications. Fortunately, the core components already existed within the lab and could be used to develop a purpose-built goniometer for specialized experimental setups. To do this, a Chemyx 200X precision syringe pump and an AmScope SM-1T microscope equipped with an MU303B digital camera were integrated into one system using standard hardware and 3D-printed parts designed with SolidWorks. The design allowed for precise control of both needle and microscope positions. A Newport tip-tilt stage was also added to the system to provide a level surface for measurements. The software development kits (SDKs) were linked through a Python script, which allowed for a dedicated GUI to be used to control both systems in a single application. Angle analysis could be performed using publicly available software meant for commercial systems. This combination of hardware and software created an instrument capable of collecting contact angle measurements.