Ammonium heteropolyacid catalized polymerization of olefins

Details Ammonium heteropolyacid catalized polymerization of olefins Ammonium heteropolyacid catalized polymerization of olefins

1999-06-24

2002-02-12

Wu, David W. (Department: 1713)

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

Synthetic resins

Polymers from only ethylenic monomers or processes of...

C526S172000, C526S233000, C526S348700, C502S210000, C502S211000

Reexamination Certificate

active

06346585

ABSTRACT:

BACKGROUND OF THE INVENTION
The present invention provides a method for preparing high vinylidene polyisobutylene by polymerizing isobutylene with a solid catalyst of a calcined ammonium salt of a heteropolyacid.
It is well known to polymerize olefins using boron trifluoride (BF
3
). The polymers so produced are highly reactive due to a large percentage of their terminal groups having vinylidene structure. The reactivity of polyolefins has been related to double bond content and the location thereof in the polymer.
U.S. Pat. No. 4,152,499, Boerzel et al., May 1, 1979, discloses the synthesis of polyisobutylene polymers having a degree of polymerization of 10 to 100 units and a high proportion of reactive double bonds. The isobutene is polymerized with boron trifluoride as the initiator at −50° C. to +30° C. The polymer contains a proportion of double bonds capable of reacting with maleic anhydride of 60 to 90% of theory. The adducts from the polyisobutylene/maleic anhydride are reacted with polyamines to form products useful as lubricating oil additives.
Polyolefins have also been prepared by polymerization catalyzed with heteropolyacids. U.S. Pat. No. 5,710,225, Johnson et al., Jan. 20, 1998, discloses a method for producing polymers by polymerization of olefins, by contacting a C
2
-C
30
olefin or derivative thereof with a heteropolyacid. The heteropolyacid catalyst can be a partially or fully exchanged with cations from the elements in groups IA, IIA and IIIA of the periodic chart, Group IB-VIIB elements and Group VIII metals, including manganese, iron, cobalt, nickel, copper, silver, zinc, boron, aluminum, bismuth, or ammonium or hydrocarbyl-substituted ammonium salt. The heteropolyacids can be used in their initial hydrated form or they can be treated (calcined) to remove some or all of the water of hydration. The calcining is preferably conducted in air at a temperature of, for instance, up to 375° C.; temperatures much over 350° C. do not generally provide much advantage. In the resulting polymers, the combined terminal vinylidene and &bgr;-isomer content is preferably at least 30%.
U.S. Pat. No. 2,982,799 (Klinkenberg, May 2, 1961) reports that at about 20-200° C. isobutylene can be polymerized by use of a specially prepared heteropolyacid catalyst. The catalyst consisted of a heteropolyacid deposited on a solid carrier. The solid carrier had an alkali (including ammonium) content of less than one milliequivalent per 100 grams of carrier and a silico-tungstic acid concentration of 0.5-8% by weight of the total catalyst. The system resulted in oligomers up to C
16
from isobutylene, or a degree of polymerization of four. The temperature used was above 20° C.
It is believed to be desirable to use highly reactive polyolefins to prepare hydrocarbyl-substituted acylating agents (e.g., anhydrides) by way of a thermal route rather than a chlorine catalyzed route. The thermal route avoids products containing chlorine. The reactivity of the polyolefin is believed to be related to the end group in the polymer with terminal olefins (terminal vinylidene) and terminal groups capable of being isomerized thereto being identified as the reactive species. The groups capable of being isomerized to the terminal vinylidene (I) group are the &bgr;-isomers (II) of Table 1.
As used herein, the term “hydrocarbyl substituent” or “hydrocarbyl group” is used in its ordinary sense, which is well-known to those skilled in the art. Specifically, it refers to a group having a carbon atom directly attached to the remainder of the molecule and having predominantly hydrocarbon character. Examples of hydrocarbyl groups include hydrocarbon substituents, substituted hydrocarbon substituents, and hetero substituents, that is, substituents which, while having a predominantly hydrocarbon character, contain other than carbon in a ring or chain otherwise composed of carbon atoms. In general, no more than two, preferably no more than one, non-hydrocarbon substituents will be present for every ten carbon atoms in the hydrocarbyl group; typically, there will be no non-hydrocarbon substituents in the hydrocarbyl group.
Conventional polyolefin synthesis involves Friedel-Crafts type catalysts reacting with terminal olefins such as isobutene or mixtures of compounds such as a C
4
raffinate from a cat cracker or an ethylene plant butane/butene stream. The polyolefins so synthesized are not noted for having high terminal vinylidene contents and are thus not the reagents of choice to use the thermal route to forming polyolefin substituted succinic anhydrides. Conventional polyisobutylene (“PIB”) when used in thermal condensation procedures with maleic anhydride give low yields and high tar contents and low succination ratios. The thermal route to substituted succinic anhydrides using highly reactive PIB's has been discussed in detail in U.S. Pat. Nos. 5,071,919, 5,137,978, 5,137,980 and 5,241,003, all issued to Ethyl Petroleum Additives, Inc.
The isomer content of a conventional (AlCl
3
) and high terminal vinylidene PIB's are shown in Table 1. Conventional PIB has terminal vinylidene content of roughly 5%. The terminal isomer groups of conventional PIB and high vinylidene PIB are given below in Table 1 and those published in EPO 0355 895. However, in this invention polyisobutylene containing relatively high content of vinylidene and &bgr;-isomers can be formed. Such materials can contain at least 30 percent terminal vinylidene (I) and &bgr;-isomer (II) groups, as shown below. In preferred cases the polyisobutylene can contain at least 30 percent terminal vinylidene (I) groups, and more preferably at least 60 percent terminal vinylidene groups.
TABLE 1
PIB Terminal Groups
Percent in Conventional PIB

4-5%

I
Vinylidene (&agr;-olefin)


II
&bgr;-Isomer (of vinylidene)

63-67%

III
Tri-substituted

22-28%

IV
Tetra-substituted


IVA

5-8%

V
Other
 0-10%
As can be seen from the structures in Table 1, conventional PIB is characterized by very low terminal vinylidene groups (I) and species capable of isomerization therewith (II). Conventional PIB further comprises a distinct tri-substituted terminal olefin group (III) which is nearly absent or present in only a low level in high vinylidene PIB. The distinct terminal group III is a 2-butene in which the 2-carbon is tri-substituted.
Structure IVA of Table 1 is an acid-catalyzed rearrangement product of IV while V is an internal vinylidene group. The terminal group content of conventional and high vinylidene PIBs have been determined by NMR analysis. Conventional PIBs are commercially available under various tradenames including Parapol® from Exxon, Lubrizol® 3104, 3108 from Lubrizol and Indopol® from Amoco and Hyvis® from BP. Conventional PIBs have number average molecular weight in the range of 300-5000, but the preferred number average molecular weight is in the range of 500-2000.
SUMMARY OF THE INVENTION
The present invention provides a method for producing polymers by polymerization of at least one olefin, the method comprising:
contacting (a) at least one C
2
-C
30
olefin or polymerizable derivatives thereof with (b) a catalyst comprising a partially or fully neutralized ammonium salt of a heteropolyacid,
wherein said catalyst has been calcined at above 350° C. to 500° C.;
whereby the efficiency of polymerization is increased compared to the efficiency in the absence of such calcining.
The present invention further provides polymers of isobutylene having a {overscore (M)}
n
of at least 1500, {overscore (M)}
w
/{overscore (M)}
n
of greater than 4, preferably 7.5 to 20, and preferably at least 30% terminal vinylidene (I) groups.
DETAILED DESCRIPTION OF THE INVENTION
Heteropolyacid catalysts can exist as the free acid or as a salt of a heteropolyanion. Heteropolyanions are polymeric oxoanions formed by a condensation reaction of two or more different oxoanions, e.g.,
12WO
4
2−
+HPO
4
2−
+23H
+
→(PW
12
O
40
)
3−
+12H
2
O
A variety of structures are known for these materials; they can have,

Affiliated with

Also associated with

Rating

Ammonium heteropolyacid catalized polymerization of olefins does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Ammonium heteropolyacid catalized polymerization of olefins, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ammonium heteropolyacid catalized polymerization of olefins will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2951821