Copolymer and a method for manufacturing

Sufficient dynamic water repellency to the surface of an article, air-drying Kobachi aqueous and can be granted the friction durability, and environmental load is low copolymer, a method of manufacturing the same, water repellent composition, and dynamic water repellency, after air drying It provides an excellent article in water repellency and friction durability. And a structural unit based on the following monomer (a) based on structural units and the following monomer (b), of the total structural units (100 mass%), structural units derived from monomer (a) ratio is 5 to 95 wt%, the proportion of structural units based on monomer (b) is 5 to 60 wt%, based on structural units and monomer derived from monomer (a) (b) total water repellent composition containing a copolymer and the copolymer which is a 65 wt% or more the content of the structural unit. Monomer (a): no polyfluoroalkyl group, carbon atoms having an alkyl group of 20 to 30 (meth) acrylate. Monomer (b): halogenated olefin.