| 摘要 |
PURPOSE: A composition for weather strip is provided to provide aesthetic effect for vehicle users in the side of interior design, to provide excellent abrasion resistance due to repeated getting in and out of vehicle uses, and to apply for the surface layer of weather strip. CONSTITUTION: A composition for weather strip comprises 0.6-1 parts by weight of a cross linking agent, 0.15-0.5 parts by weight of a cross linking aid, 0.2-0.5 parts by weight of a foaming agent, 3-5 parts by weight of a nanocrystal structured elastomer, 0.2-0.6 parts by weight of an antioxidant, 10-20 parts by weight of inorganic filler, 0.3-0.6 parts by weight of polypropylene based wax, and 60-100 parts by weight of process oil, based on 100 parts by weight of a matrix resin. The matrix resin comprises 50-80 weight% of EPDM rubber, and 20-50 weight% of long branched chain-containing polypropylene. The Mooney viscosity of the EPDM at 125°C is 80 or higher, and the content of 5-ethylidene-2-norbornene in the EPDM is 8 weight% or higher. The melt index of the long branched chain-containing polypropylene is 0.2-0.5(230°C, 2.16 kg). The cross-linking agent is 2,5-dimethyl-2,5-di-(tertiary butylperoxy)hexane. |
