Exxon Mobil has been granted a patent for compositions containing polyolefin, hindered phenol, and phenyl phosphite as antioxidants. The concentration of hindered phenol and phenyl phosphite ranges from 10 ppm to 5000 ppm, with the hindered phenol amount being less than the phenyl phosphite. These compositions are used as antioxidants in polyolefin materials. GlobalData’s report on Exxon Mobil gives a 360-degree view of the company including its patenting strategy. Buy the report here.
According to GlobalData’s company profile on Exxon Mobil, microscale biofuel reactors was a key innovation area identified from patents. Exxon Mobil's grant share as of September 2023 was 65%. Grant share is based on the ratio of number of grants to total number of patents.
A recently granted patent (Publication Number: US11773235B2) discloses a composition comprising at least one polyolefin, a hindered phenol, and a phenyl phosphite. The concentration of the hindered phenol and the phenyl phosphite in the polyolefin ranges from 10 ppm to 5000 ppm, with the hindered phenol present in a lower amount than the phenyl phosphite. These two antioxidants are the only ones present in the composition. The polyolefin can be a polypropylene homopolymer or copolymer, including ethylene derived units or units derived from C4 to C12 a-olefins. Alternatively, it can be an impact copolymer.
The patent also describes a process for producing the composition. The process involves contacting one or more monomers selected from C2 to C12 a-olefins with a catalyst to form polyolefin granules. The granules are then purged with nitrogen at a temperature greater than 50°C and mixed with additives, including the hindered phenol and phenyl phosphite, to form a mixture. The mixture is melt blended at a temperature of at least 200°C. The overall concentration of the hindered phenol and the phenyl phosphite in the polyolefin during the process ranges from 10 ppm to 5000 ppm, with the hindered phenol present in a lower amount than the phenyl phosphite. Only these two antioxidants are used in the process.
Furthermore, the patent discloses a composition that includes a blend of a polypropylene homopolymer and an a-olefin copolymer, with the overall concentration of the hindered phenol and the phenyl phosphite ranging from 10 ppm to 5000 ppm. The a-olefin copolymer can contain ethylene derived units or units derived from C4 to C12 a-olefins, within a range of 0.1 to 30 wt %.
This patent provides a composition and a process for producing it, which includes specific concentrations of hindered phenol and phenyl phosphite antioxidants in polyolefins. The disclosed composition and process can be used in various applications where the use of antioxidants is required, such as in the production of polypropylene-based materials. The specific concentrations and combination of antioxidants described in the patent may offer improved stability and performance properties to the polyolefin compositions.