Copolymer, production process thereof, lubricating oil viscosity modifier, and lubricating oil composition
US7915358B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 13, 2009 |
| Grant date | Mar 29, 2011 |
| Priority date | — |
| Expiry date | Feb 13, 2029 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10N2030/02
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Copolymers when used as lubricating oil viscosity modifiers enable lubricating oils to show excellent low-temperature properties. Processes for producing the copolymers are disclosed. Lubricating oil viscosity modifiers and lubricating oil compositions contain the copolymers.A copolymer includes structural units derived from ethylene and structural units derived from a C3-20 α-olefin and satisfies the following requirements (1) to (8): (1) the melting point (Tm) according to DSC is in the range of 0 to 60° C.; (2) the melting point (Tm) and the density D (g/cm3) satisfy the equation: Tm≧1073×D−893; (3) Mw/Mn according to GPC is from 1.6 to 5.0; (4) the half-value width (ΔThalf) of a melting peak measured by DSC is not more than 90° C.; (5) the half-value width (ΔThalf) and the melting point (Tm) satisfy the equation: ΔThalf≦−0.71×Tm+101.4; (6) the heat of fusion (ΔH) as measured by DSC is not more than 60 J/g; (7) the crystallization temperature (Tc) measured by DSC is not more than 70° C.; (8) the heat of fusion (ΔH), the crystallization temperature (Tc), each measured by DSC and the crystallization temperature measured by a CRYSTAF method (Tcrystaf) satisfy the equation: Tc−Tcrys…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.