The GB/T 20186.2-2008 standard focuses on modified polypropylene (PP) in secondary coating materials for optical fibers. It specifies various technical requirements for modified polypropylene (PP) as secondary coating materials for optical fibers, including material performance, test methods, inspection rules, etc. This standard helps to ensure the mass of modified polypropylene (PP) in optical fiber protection applications, provides an important basis for optical fiber manufacturers to select suitable materials and ensure the Stability and Reliability of optical fiber products, and promotes the development of material standardization in the optical fiber communication industry.