Structure and Characteristics of Flexible Chain Polyformaldehyde Fibers With Mechanical Performance Based on Orientation‐Induced Fibrillation

ABSTRACT The flexible chain polyoxymethylene (POM) fibers have historically faced challenges regarding their mechanical properties, issues that have been a focal point for researchers. The enhanced mechanical properties of fibers require the crystalline regions and macromolecular chains’ orientation along the axial direction within the fibers, forming fibrillation. They were affected by the regulation of melt spinning process parameters, including crystallinity and orientation, accomplished by high thermal drawing ratios. This paper successfully produced POM drawn fibers (POM D ) with high strength, high modulus, and improved creep resistance by manipulating the internal aggregation of POM fibers through thermal drawing. A thorough comparison was conducted in this paper between POM D and both flexible chain polyethylene (PE) drawn fibers and POM as‐spun fibers (POM A ), highlighting the relationship between orientation, crystallization, and fibrillation and the importance of thermal drawing in augmenting the fibers' mechanical properties.