Alpha crystalline modification of 2,2',2'-nitrilo(triethyl-tris-(3,3',5,5'-tetra-tert-butyl-1, 1'-biphenyl-2,2'-diyl)phosphite)

摘要

The alpha crystalline modification of 2,2',2''-nitrilo[triethyl-tris-(3,3',5,5'-tetra-tert-butyl-1,1'-biphenyl-2,2'-diyl)phosphite] is obtained by crystallizing said compound from selected solvents, preferably from a mixture of an aromatic hydrocarbon solvent and a lower alkanol. The alpha crystalline form is an effective process stabilizer for polyolefins, particularly polypropylene.