| 摘要 |
1,268,415. Granular polymers of propylene. BADISCHE ANILIN- & SODA-FABRIK A.G. 11 Aug., 1969 [12 Aug., 1968], No. 40067/69. Heading C3P. Easily processable granules of propylene polymer are prepared by (1) polymerizing propylene by means of a Ziegler-Natta catalyst containing titanium, in the absence of solvents or diluents so that the propylene polymer immediately obtained is in the form of a powder which contains 5-30 p.p.m. by weight of titanium, has a fraction of 10-35% by weight which is soluble in boiling n-heptane and which has an intrinsic viscosity of 6 to 10; (2) exposing the polymer, without deactivation of the catalyst, to a shear velocity of 20-1000 sec.<SP>-1</SP> at 250-350‹ C. until the intrinsic viscosity is 1.5 to 4.0 and (3) homogenizing, extruding and granulating the so treated polymer by conventional techniques. In the example, propylene is polymerized using TiCl 3 .<SP>1</SP>/ 3 AlCl 3 and Al(C 2 H 5 ) 3 to give a polymer of particle size 0.3 3 to 2.5 mm., containing 15 p.p.m. by weight of titanium, having a fraction of 27.5% which is soluble in boiling n-heptane and having an intrinsic viscosity of 7.8. 100 parts of the polymer are mixed with 0.2 parts by weight of the stearic ester of 2,6-ditert-butyl-4-methyl-6- #-hydroxyethyl phenol and 0.2 parts by weight of potassium stearate and subjected to a shear velocity of 400 sec.<SP>-1</SP> and homogenized, extruded and granulated at temperatures between 250‹ and 300‹ C. |
