摘要:
An ethylene ter- or tetrapolymer useful as a viscosity modifer and a process for preparing the polymer. The polymer comprises ethylene, an alpha-olefin, a non-conjugated diene and, optionally, a cationically polymerizable monoolefin. The polymerization catalyst comprises a Ziegler catalyst in conjunction with a cationic polymerization catalyst.
摘要:
Fluid solutions, e.g. mineral oil solutions, of polydispersed polymers have improved resistance to mechanical shear when said polymers have a narrow molecular weight distribution, i.e. ##EQU1## 10 and/or a reduced compliance less than that of a linear monodisperse polymer of the same chemical repeat unit and M.sub.w and preferably said solution at a concentration such that [.eta.] c ranges from one-tenth to five where [.eta.] is the intrinsic viscosity of the polymer in the oil and c is the concentration in the same units and/or has a compliance no larger than twenty times the value exhibited by an identical solution except that said polymer was replaced by a linear monodisperse polymer of the same chemical structure and of the same (.+-.5%) weight average molecular weight (M.sub.w).
摘要:
An ethylene ter- or tetrapolymer useful as a viscosity modifier and a process for preparing the polymer. The polymer comprises ethylene, an alpha-olefin, a non-conjugated diene and, optionally, a cationically polymerizable monoolefin. The polymerization catalyst comprises a Ziegler catalyst in conjunction with a cationic polymerization catalyst.
摘要:
Ethylene-alpha-olefin copolymers are disclosed being particularly useful as improving the low temperature viscosity and pumpability properties of lubricating oil comprised of a major and minor component each of which have a defined ethylene sequence distribution with respect to the number of ethylenes in sequences of three or more and the percent of ethylene sequences of three or more ethylene units. Ethylene-propylene copolymers are the preferred embodiment.
摘要:
A method for reducing the molecular weight of olefin copolymers comprises contacting an olefin copolymer and a base oil containing less than about 0.05 wt. % sulfur in the presence of oxygen and at a temperature of at least about 60° C.
摘要:
The present invention relates to hydrogenated block copolymers of butadiene and at least one other diene, preferably isoprene. The copolymer is hydrogenated and comprises at least 10% by weight of at least one crystallizable segment and at least one low crystallinity segment.
摘要:
The present invention relates to hydrogenated block copolymers of butadiene and at least one other diene, preferably isoprene. The copolymer is hydrogenated and comprises at least 10% by weight of at least one crystallizable segment and at least one low crystallinity segment.