Manufacture of olefin polymers

Details Manufacture of olefin polymers Manufacture of olefin polymers

1975-11-13

1977-08-16

Holler, Alan

Synthetic resins or natural rubbers -- part of the class 520 ser

Synthetic resins

Polymers from only ethylenic monomers or processes of...

252451, 423327, 423329, C08F 402, C08F 424, C08F 1000

Patent

active

040427706

ABSTRACT:
This invention relates to a process for the manufacture of olefin polymers by polymerization of monoolefins with the aid of a silicic xerogel/chromium trioxide catalyst obtained by (1) synthesizing a particulate silicic xerogel, (2) doping this xerogel with chromium trioxide or a chromium compound which converts to chromium trioxide under conditions of stage (3) and (3) maintaining the resulting product at an elevated temperature in a water-free oxygen-containing stream of gas. The characteristic feature of the process of the invention is that the silicic xerogel/chromium trioxide catalyst used is one obtained by (1) synthesizing the silicic xerogel in the first stage as follows: (1.1) taking an aqueous solution of a sodium silicate, (1.2) substituting substantially all of the sodium ions contained in said solution by hydrogen ions by means of an ion exchanger, (1.3) introducing a water-soluble aluminum salt into the resulting aqueous silicic acid solution, (1.4) adjusting the pH of the solution obtained in stage (1.3) to from 0.1 to 3.5, if necessary, (1.5) adjusting the solution obtained in (1.3) or (1.4) to a pH of from 4 to 12 by means of a nitrogen-base compound, (1.6) extracting the product forming the solid phase in stage (1.5) (silicic hydrogel) by means of an alkanol and/or alkanone until the organic liquid absorbs no more water and, finally, (1.7) drying the dehydrated gel saturated with organic liquid resulting from stage (1.6) (xerogel formation). This process makes it possible to obtain polymers having a satisfactory particle size distribution and a favorable melt index.

REFERENCES:
patent: 3652216 (1972-03-01), Krekeler et al.
patent: 3900457 (1975-08-01), Witt
patent: 3960826 (1976-06-01), Aboutboul et al.

Affiliated with

Also associated with

Rating

Manufacture of olefin polymers does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Manufacture of olefin polymers, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Manufacture of olefin polymers will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-362153