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A lab scale continuous process solvent-based prepreg manufacturing machine (prepreg treater) is a useful tool for small-scale production runs carried out by research teams involved in various projects related to advanced composites. Such a machine can also be used in school laboratories for teaching purposes. However, industrial compact prepreg treaters available for purchase are prohibitively expensive.This document details the work done by undergraduate students at Western Washington University to design, develop, and qualify a modestly budgeted, solvent-based prepreg manufacturing machine to be used for investigation of new prepreg resin systems. The steps undertaken to manufacture the machine and qualify it are explained in detail and can be helpful to educational institutions that may have requirements of such a treater for research and/or teaching. DefinitionsPrepreg is commonly defined as a reinforced fabric that has been impregnated with a resin matrix. It is frequently used in place of a traditional hand layup for a number of reasons, including increased control over resin content, decreased scrap and mess, and generally improved reproducibility during processing.[1] Following impregnation of the pre-polymeric resin system into fibers, the prepreg is considered B-staged. At this point in processing, the resin has undergone a partial cure and begun to crosslink. As such, storage in freezers is required, to prevent further crosslinking of the material into a fully cured C-stage product. [2] Prepreg is manufactured primarily using two processes: solvent coating and hot melt coating. In the solvent coating process, fabric is threaded between metal rollers and run through a resin bath, then fed through a series of ovens to partially cure the material. Following a short cooling period, the prepreg is ultimately wound up at the other end of the machine into a roll, for ease of storage [3]. The resin in the bath is dissolved in a solvent, typically an alcohol or acetone, to reduce its viscosity and increase its ability to penetrate the fibers. The solvents are released as volatiles in large in-line ovens as a part of the process during B-staging. In contrast, to produce prepreg using hot melt coating, fabric is run through a carrier paper containing a fixed quantity of resin, followed by the application of pressure with heated compaction rollers. This simultaneously impregnates the fabric and B-stages the resin. The fabric is then cooled and the paper removed.

Community College Ms. Larson is currently an assistant professor in the engineering technology department of Western Washington University. Before this appointment, she was an instructor in the materials science technology program for Edmonds Community College. There she is developed the coursework and laboratory experiments necessary to make the new program a success. She has 6 years of industry experience implementing lean manufacturing techniques, managing development projects, and leading cross-functional teams to assess technical capability of suppliers and strategic partnerships. She also has several years experience in the composites and ceramics manufacturing arenas. Ms. Larson holds a Master of Science in Mechanical Engineering from the University of Washington and a Bachelor of Science in Mechanical Engineering from Bradley University. Eric Davishahl, Everett Community College Eric Davishahl holds an MS in Mechanical Engineering from the University of Washington with a specialization in energy and fluid mechanics. Prior to joining the faculty at Everett Community College in 2001, Eric worked for Nu Element Inc, a fuel cell technology research and development company and at Energy International Inc. an energy industry consulting company in Bellevue, WA. He was selected as the George Shuh outstanding faculty member at Everett Community College for the 02-03 academic year.

After receiving my bachelor degree in Mechanical Engineering from Bradley University, I started working for Boeing. While at Boeing I worked to receive my master's degree in Mechanical Engineering with an emphasis in Materials and Manufacturing. After leaving Boeing I spent several years in equipment research and development at Starbucks Coffee Company. From there I decided my heart lied in teaching and left Starbucks to teach Materials Science Technology at Edmonds Community College. I eventually moved to Western Washington University where I have been faculty in the Plastics and Composites Engineering Program (formerly Plastics Engineering Technology) for the past 13 years. My research interests are in composite manufacturing.