Polyethylene wax - by polymerising in a tubular reactor with different temp zones and alkanal regulator

摘要

Low m. wt. waxy polyethylene is prepd. by continuously reacting 100 pts. wt. ethylene, which contains 0.05-50 mole - ppm (based on ethylene) radical polymsn. initiator and 0.5-10 pts. wt. polymerisation regulator selected from 3-6C alkanols at elevated temp. and 1000-3000 atm in a tubular reactor with a ratio of tubes length:tube inner diameter of 5000:1 to 30000:1, the mixt. passing through the reactor at a velocity of 3-30 m/sec. The polymsn. mixt. is introduced into the reactor at a temp. of 90-140 degrees C, is brought gradually to a temp. of 230--300 degrees C in the first 5/15 of the length of the reactor, is held at a constant temp. of 230-300 degrees C plus-or-minus 5 degrees C in the next 9/15 of the reactor length, and is cooled to 50-100 degrees C in the last 1/15 of the length of the reactor. Product has excellent softening range melt viscosity and hardness and good oil binding properties.