Wettability and Surface Roughness of Parylene C on Three-Dimensional-Printed Photopolymers

The use of poly-(para-chloro-xylylene) (Parylene C) in microelectromechanical systems and medical devices has increased rapidly. However, little research has been conducted on the wettability and surface roughness of Parylene C after being soaked in solutions. In this study, the contact angle and surface roughness (arithmetic average of roughness) of Parylene C on three-dimensional (3D)-printed photopolymer in 10% sodium hydroxide, 10% ammonium hydroxide, and 100% phosphate-buffered saline (PBS) solutions were investigated using a commercial contact angle measurement system and laser confocal microscope, respectively. The collected data indicated that 10% ammonium hydroxide had no major effect on the contact angle of Parylene C on a substrate, with a Shore A hardness of 50. However, 10% sodium hydroxide, 10% ammonium hydroxide, and 100% PBS considerably affected the contact angle of Parylene C on a substrate with a Shore A hardness of 85. Substrates with Parylene C coating exhibited lower surface roughness than uncoated substrates. The substrates coated with Parylene C that were soaked in 10% ammonium hydroxide exhibited high surface roughness. The aforementioned results indicate that 3D-printed photopolymers coated with Parylene C can offer potential benefits when used in biocompatible devices.