Maleated high acid number high molecular weight polypropylene of low color
AssigneeEastman Chemical Company
InventorsThomas David Roberts, Stephen Wayne Coe
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Abstract
A process for the manufacture of maleated polypropylenes having an acid number greater than 4.5, a yellowness index color of no greater than 76, and a number average molecular weight of at least 20,000. The process for making the maleated polypropylenes includes forming a mixture of molten polypropylene and molten maleic anhydride in a reactor, introducing a free radical initiator into the molten mixture to produce a product having maleic anhydride grafted onto the polypropylene, and recovering a high acid number, high molecular weight maleated polypropylene of low color from the reactor.
Claims18
A composition of matter comprising a maleated polypropylene having an acid number greater than 6, a yellowness index color of no greater than 76, and a number average molecular weight of at least 20,000.
A maleated polypropylene having an acid number greater than 6, a yellowness index color of no greater than 76, and a number average molecular weight of at least 20,000 prepared by the process comprising:
- a. in a reactor, forming a molten mixture comprising a polypropylene and maleic anhydride;
- b. mixing a reaction initiator into the molten mixture under condition suitable for producing a product having said maleic anhydride grafted onto said polypropylene;
- and
- c. recovering said product,
- wherein the weight ratio of polypropylene to maleic anhydride is about 10 to 200, the molar ratio of polypropylene to free radical initiator is about 200 to 4,000, and the molar ratio of maleic anhydride to free radical initiator is about 1 to 70.
Dependencies are inferred from the claim text.