The Establishment of a High-throughput Characterization Platform and Database for Film Blowing Processing-Structure-Performance

M.N. Zhang¹, E.J. Yang¹, J.Y. Zhao¹, W. Chen^1*, P.C. Yin², L.B. Li^1*

¹University of Science and Technology of China, Hefei, 100083

²South China University of Technology, Guangzhou, 510641

ABSTRACT: Film blowing is an important material processing technology for preparing film materials such as packing film. The process of film blowing is affected by the external force field, the temperature field, polymer structure evolution, which is a multi-physical field coupling process and hard to predict the structure and performance of the film accurately. Therefore, the solution to many problems in the film blowing process (such as multi-layer co-extrusion, polymer structure evolution, etc.) will bring broader research and application prospects for film blowing. In this work, we take advantage of the synchrotron radiation X-ray technology and develop a set of A/B/A three-layer co-extrusion film blowing device used with it. Equipped with elevator, infrared temperature measurement, and other support devices, the in-situ detection for the multi-layer co-extrusion blowing process is realized, in which we can obtain the bubble structure (precursor, lamella, etc.) and evolution information (long period, orientation, crystallinity, etc.) of the film blowing process. Based on this, we develop the X-ray analysis software smart X, which can perform X-ray two-dimensional image correction, WAXS crystallinity calculation, SAXS orientation calculation, and other functions. The in-situ research device of film processing has been designed and manufactured. Through the connection with the film blowing device, the mechanical and optical properties of the polymer film can be carried out. Integrating the edge-detection algorithm based on RCF (Richer Convolutional Features) neural network, the supporting software Blown is tested and developed, which can be used to track the shape of the bubble in the process of film blowing. Based on that, we then calculate the frost line and stability of the bubble. Afterward, combined with the in-situ research device, automatic operation, data collection, analysis, and real-time storage can be realized. The work in this part has realized the rapid quantitative characterization of polymer materials from the film manufacturing to the mechanical and optical properties, which has provided the foundation for the realization of intelligent processing of polymer equipment. A new idea for the establishment of the relationship map between processing conditions - structure - properties of polymer materials is provided in this work.

 Fig.1 Schematic of in-situ research facility for film processing

Keywords: Film blowing; Synchrotron radiation characterization; High-throughput characterization platform; Neural network recognition algorithm