VISCOSITY MODIFIER FOR LUBRICATING OIL AND LUBRICATING OIL COMPOSITION
    7.
    发明授权
    VISCOSITY MODIFIER FOR LUBRICATING OIL AND LUBRICATING OIL COMPOSITION 有权
    用于润滑油和润滑油组合物的粘度改进剂

    公开(公告)号:EP1148115B1

    公开(公告)日:2005-06-29

    申请号:EP99959693.5

    申请日:1999-12-08

    摘要: The present invention is intended to obtain a viscosity modifier for a lubricating oil, by the use of which a lubricating oil composition of excellent low-temperature properties can be obtained, and to obtain a lubricating oil composition of excellent low-temperature properties containing the viscosity modifier. The viscosity modifier for a lubricating oil comprises an ethylene/propylene copolymer (A) having the properties: the density is in the range of 857 to 882 kg/m , Mw is in the range of 80,000 to 400,000, Mw/Mn is not more than 2.3, and the density (D (kg/m )) and the melting point (Tm ( DEG C)) satisfy the relation Tm≤1.247xD-1037; or comprises an ethylene/propylene copolymer (B) having the properties: the ethylene content is in the range of 70 to 79 wt%, Mw is not less than 80,000 and less than 250,000, Mw/Mn is not more than 2.3, Tm is in the range of 15 to 60 DEG C, and the ethylene content (E (wt%)) and the melting point (Tm ( DEG C)) satisfy the relation 3.44xE-206≥Tm; or comprises an ethylene/propylene copolymer (C) having the properties: the ethylene content is in the range of 70 to 79 wt%, Mw is in the range of 250,000 to 400,000, Mw/Mn is not more than 2.3, Tm is in the range of 15 to 60 DEG C, and the ethylene content (E (wt%)) and the melting point (Tm ( DEG C)) satisfy the relation 3.44xE-204≥Tm. The lubricating oil composition comprises the ethylene/propylene copolymer (A) (B) or (C), a lubricating oil base (D), and if necessary, a pour point depressant.