US4486575A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the manufacture of halogenated elastomers
Assignee: ExxonMobil Technology and Engineering Co
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Filing: 1983-04-01
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Granted: 1984-12-04
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Expires: 2003-04-01
Abstract
Abstract Continuous halogenation of olefinically unsaturated rubber is achieved in an extruder-reactor employing reactants, conditions and design features directed to maximizing mixing and contact of the rubber with the halogenating agent and neutralizing agent while simultaneously minimizing side reactions and polymer degradation. The rubber passes through three extruder-reactor zones under controlled conditions to achieve halogenation: feed, reaction, and neutralization; optionally a wash and exit zone can be utilized. The halogenated rubber, for example, halogenated butyl rubber can be vulcanized in the absence of sulfur, e.g., with zinc oxide and stearic acid, and is useful in all applications where commercially available chlorinated and brominated rubbers are presently employed.
Inventors
- 👤 Neil F. Newman
- 👤 Ronald C. Kowalski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:35
CPC Classifications
C; C08; C08L; C08L21/00; C08F; C08F8/00; C08F8/18; C08F8/20; C08C; C08C19/00; C08C19/12; C08F8/22; Y; Y02; Y02P; Y02P20/00; Y02P20/141; Y02P20/143
Claims Analysis
Total Claims: 44
Claim 1
Independent Claim
218 words
A process for the continuous production of halogenated rubber by reacting an olefinically unsaturated rubber and a halogenating agent in an extruder-reactor, said extruder-reactor comprising feed zone (A), reaction zone (B) and neutralization zone (C) in sequence; screw means traversing zones (A) through (C); first flow restriction means following feed zone (A); injection means for supplying halogenating agent to reaction zone (B); mixing means for subjecting rubber in reaction zone (B) to a high degree of mixing; second flow restriction means disposed between reaction zone (B) and neutralization zone (C); and injection means disposed at or adjacent the downstream end of the second flow restriction means for supplying neutralizing agent to the product mixture; further comprising subjecting rubber in the feed zone to conditions of temperature and pressure sufficient to generate a cohesive mass; conveying said mass past said first restriction means to said reaction zone; halogenating the rubber in said reaction zone by injecting halogenating agent at a position filled with said rubber and subjecting the reactants to a high degree of mixing; conveying the product mixture past said second restriction means; injecting neutralizing agent at or adjacent the downstream end of said second restriction means; neutralizing said product mixture with said neutralizing agent in said neutralizing zone; and delivering said halogenated rubber product from the extruder-reactor
Claim 2
Dependent Claim
218 words
A process for the continuous production of halogenated rubber by reacting an olefinically unsaturated rubber and a halogenating agent in an extruder-reactor, said extruder-reactor comprising feed zone (A), reaction zone (B) and neutralization zone (C) in sequence; screw means traversing zones (A) through (C); first flow restriction means following feed zone (A); injection means for supplying halogenating agent to reaction zone (B); mixing means for subjecting rubber in reaction zone (B) to a high degree of mixing; second flow restriction means disposed between reaction zone (B) and neutralization zone (C); and injection means disposed at or adjacent the downstream end of the second flow restriction means for supplying neutralizing agent to the product mixture; further comprising subjecting rubber in the feed zone to conditions of temperature and pressure sufficient to generate a cohesive mass; conveying said mass past said first restriction means to said reaction zone; halogenating the rubber in said reaction zone by injecting halogenating agent at a position filled with said rubber and subjecting the reactants to a high degree of mixing; conveying the product mixture past said second restriction means; injecting neutralizing agent at or adjacent the downstream end of said second restriction means; neutralizing said product mixture with said neutralizing agent in said neutralizing zone; and delivering said halogenated rubber product from the extruder-reactor
Claim 3
Dependent Claim
32 words
The process of claim 1 wherein said olefinically unsaturated rubber is selected from the group consisting of butyl rubber, EPDM rubber, styrene butadiene rubber, polyisoprene rubber, polybutadiene rubber, and poly(butadiene-isoprene) copolymer rubber.
Claim 4
Dependent Claim
11 words
The process of claim 2 wherein said rubber is butyl rubber.
Claim 5
Dependent Claim
11 words
The process of claim 2 wherein said rubber is EPDM rubber.
Claim 6
Dependent Claim
40 words
The process of claim 1 wherein said halogenating agent is selected from the group consisting of chlorine gas, aqueous chlorine, sulfuryl chloride, N-Chloro-succinimide, 1,3-dichloro-5,5-dimethylhydantoin iodobenzene dichloride, iodine monochloride, bromine gas, bromine liquid, bromine chloride, sodium hypobromite, sulfur bromide and N-bromosuccinimide.
Claim 7
Dependent Claim
12 words
The process of claim 3 wherein said butyl rubber is isobutylene-isoprene copolymer.
Claim 8
Dependent Claim
25 words
The process of claim 1, further comprising adding a diluent to said rubber feed before, at or near the point of addition of said feed.
Claim 9
Dependent Claim
25 words
The process of claim 7 wherein said diluent is selected from the group consisting of volatile saturated hydrocarbons chlorohydrocarbons, chlorocarbons , non-hydrocarbons, and hydrocarbon oils.
Claim 10
Dependent Claim
28 words
The process of claim 8 wherein said diluent is selected from the group consisting of pentane, hexane, methylene chloride, chloroform, carbon tetrachloride, carbon dioxide, inert gas and water.
Claim 11
Dependent Claim
23 words
The process of 9 wherein said diluent is present at less than about 50 percent by weight based on the weight of rubber.
Claim 12
Dependent Claim
23 words
The process of 9 wherein said diluent is present at less than about 50 percent by weight based on the weight of rubber.
Claim 13
Dependent Claim
21 words
The process of claim 5 wherein said halogenating agent is selected from the group consisting of bromine, chlorine and bromine chloride.
Claim 14
Dependent Claim
13 words
The process of claim 5 wherein said halogenating agent is diluted with diluent.
Claim 15
Dependent Claim
11 words
The process of claim 12 wherein said halogenating agent is chlorine.
Claim 16
Dependent Claim
24 words
The process of claim 12 wherein said diluent is a gas selected from the group consisting of nitrogen, argon, air and CO 2 .
Claim 17
Dependent Claim
44 words
The process of claim 7 wherein said halogenating agent is diluted with a diluent and wherein the total amount of diluent added to said feed and halogenating agent diluent is less than about 50 percent by weight based on the weight of butyl rubber.
Claim 18
Dependent Claim
27 words
The process of claim 15 wherein said diluent added to said feed is selected from the group consisting of volatile saturated hydrocarbons, chlorohydrocarbons, chlorocarbons and hydrocarbon oils.
Claim 19
Dependent Claim
32 words
The process of claim 1 wherein said neutralizing agent is an aqueous base, said aqueous based selected from the group consisting of hydroxide, bicarbonates and carbonates of alkali and alkaline earth metals.
Claim 20
Dependent Claim
15 words
The process of claim 1 further comprising the step of washing said neutralized product mixture.
Claim 21
Dependent Claim
36 words
The process of claim 18 wherein the washing step is performed in an extruder wash zone (D) which follows the neutralization zone (C), prior to delivering the halogenated rubber product from the exit of the extruder.
Claim 22
Dependent Claim
12 words
The process of claim 1 further comprising a final exit zone (E).
Claim 23
Dependent Claim
40 words
The process of claim 18 wherein washing is performed by means of one or more streams of water directed countercurrent to and/or concurrent with the flow of neutralized halogenated rubber to remove therefrom fluid and non-polymer-bound materials other than water.
Claim 24
Dependent Claim
28 words
The process of claim 20 wherein the temperature of said halogenated rubber is adjusted for delivery from said exit zone at a temperature lower than about 130° C.
Claim 25
Dependent Claim
18 words
The process of claim 18 wherein a degradation, oxidation or dehydrohalogenation stabilizer is added in said wash step.
Claim 26
Dependent Claim
18 words
The process of claim 20 wherein a degradation, oxidation or dehydrohalogenation stabilizer is added to said exit zone.
Claim 27
Dependent Claim
23 words
The process of claim 19 wherein said extruder-reactor further comprises filter means to effect the separation of non-polymer-bound materials from said halogenated rubber.
Claim 28
Dependent Claim
39 words
The process of claim 1 wherein said restriction means following said feed zone is selected from the group consisting of a reverse flighted screw section, a filled screw section, a shallow flighted screw section, and an unflighted screw section.
Claim 29
Dependent Claim
19 words
The process of claim 26 wherein said restriction means is about 0.5 to about 8 screw diameters in length.
Claim 30
Dependent Claim
17 words
The process of claim 1 wherein said restriction means following said feed zone comprises said reaction zone.
Claim 31
Dependent Claim
49 words
The process of claim 1 wherein said means for producing a high degree of rubber mixing is selected from the group consisting of a reverse flighted screw section, a multiple reverse flighted screw section, a pin section, and a series of very short alternating reverse and forward screw sections.
Claim 32
Dependent Claim
43 words
The process of claim 1 wherein said restriction means separating said neutralization zone from, said reaction zone is selected from the group consisting of a reverse flighted screw section, a filled screw section, a shallow flighted screw section, and an unflighted screw section.
Claim 33
Dependent Claim
18 words
The process of claim 6 wherein the temperature in said reaction zone is less than about 170° C.
Claim 34
Dependent Claim
42 words
The process of claim 26 wherein said restriction means is an unflighted screw section with a diameter of from 5 to 25 percent larger than the root diameter of the upstream screw section, but not greater than the upstream screw flight diameter.
Claim 35
Dependent Claim
42 words
The process of claim 30 wherein said restriction means is an unflighted screw section with a diameter of from 5 to 25 percent larger than the root diameter of the upstream screw section, but not greater than the upstream screw flight diameter.
Claim 36
Dependent Claim
12 words
The process of claim 7 wherein said diluent is a hydrocarbon oil.
Claim 37
Dependent Claim
14 words
The process of claim 1 wherein said extruder screw means is a twin screw.
Claim 38
Dependent Claim
14 words
The process of claim 1 wherein said extruder screw means is a single screw.
Claim 39
Dependent Claim
11 words
The process of claim 12 wherein said halogenating agent is bromine.
Claim 40
Dependent Claim
12 words
The process of claim 12 wherein said halogenating agent is bromine chloride.
Claim 41
Dependent Claim
32 words
The process of claim 1 wherein a high degree of mixing is achieved in said reaction zone by operating the extruder screw at a rotation rate of from 100 to 600 RPM.
Claim 42
Dependent Claim
37 words
The process of claim 1 wherein the material used in the construction of one or more of said zones is selected from the group consisting of a Hastelloy alloy, steel coated with inert polymer or a ceramic.
Claim 43
Dependent Claim
23 words
The process of claim 1 wherein the rubber in the feed zone is subjected to a pressure of up to about 600 psig.
Claim 44
Dependent Claim
34 words
The process of claim 1 wherein, at the position of injection of the halogenating agent into the reaction zone, the rubber mass is at a pressure of from about 15 to about 400 psig.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-12-04 | 1988-06-04 | 1988-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-12-04 | 1992-06-04 | 1992-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-12-04 | 1996-06-04 | 1996-12-04 | $7700.00 | Window Closed / Lapsed |