A solvent extraction method for determinating ethylene/propylene copolymer content in OCP type viscosity index improver was introduced. The analytical results indicated that the method was simple, convenient, rapid and accurate.是什么意思_A solvent extraction method for determinating ethylene/propylene copolymer content in OCP type viscosity index improver was introduced. The analytical results indicated that the method was simple, convenient, rapid and accurate.在线翻译_英语_读音_用法_例句