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US3725370A Expired / Lapsed US ⏱️ 0.0 years remaining

Process and product of treating live polymers with divinyl benzene and an active halogen compound

Assignee: Bridgestone Firestone Inc
•
Filing: 1971-01-06
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Granted: 1973-04-03
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Expires: 1991-01-06
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Abstract

Abstract The process described herein involves a method of converting relatively low molecular weight polymers of conjugated dienes prepared by alkali metal-catalyzed polymerizations, such as alkyllithium catalyzed polymerizations, and still containing active lithium or other alkali metal therein, by post-reaction with a mixture of divinyl benzene and a halocompound having highly active halogen, such as bis(chloromethyl) ether, to give higher molecular weight polymers having improved cold flow resistance, processability, green strength, oil extendability, etc. The improvements are much greater than can be effected by postreaction with either the divinyl benzene or the highly active halocompound individually, or by having divinyl benzene present during the polymerization. The highly active halocompounds include chloro, bromo and iodo compounds in which the halogen is attached to a carbon atom alpha to an activating group such as a polar or unsaturated group. The postreacted products are highly branched elastomers having a broad molecular weight distribution and possessing less cold flow than the polymers from which they are produced. Surprisingly, even though the molecular weight of the polymer is increased many times, the reaction product displays little or no tendency for cold flow even after extension with oil.

Inventors

  • 👤 A Halasa
  • 👤 E Schroeder

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 22:33
CPC Classifications
C; C08; C08C; C08C19/00; C08C19/30; C08C19/42; C08C19/44

Claims Analysis

Total Claims: 17
Claim 1
Independent Claim 16 words
The process of claim 1 in which said reaction is conducted for at least one hour.
Claim 2
Dependent Claim 23 words
The process of claim 1 in which said reaction is conducted until there has been at least 50 percent increase in molecular weight.
Claim 3
Dependent Claim 12 words
The process of claim 1 in which said temperature is 20*-120* C.
Claim 4
Dependent Claim 12 words
The process of claim 1 in which said alkali metal is lithium.
Claim 5
Dependent Claim 29 words
The process of claim 1 in which said alkali metal is present in said polymer in a proportion of 0.4-0.8 millimole per 100 parts by weight of said polymer.
Claim 6
Dependent Claim 25 words
The process of claim 1 in which said active-halogen compound is used in a proportion of 0.1-25 millimoles per 100 parts by weight of polymer.
Claim 7
Dependent Claim 19 words
The process of claim 1 in which divinyl benzene is used in an amount approximately equimolar with the halogen.
Claim 8
Dependent Claim 11 words
The process of claim 1 in which said polymer is polybutadiene.
Claim 9
Dependent Claim 25 words
The process of claim 1 in which said polymer is a copolymer of butadiene and styrene containing 5-50 percent by weight of styrene copolymerized therein.
Claim 10
Dependent Claim 13 words
The process of claim 1 in which said active-halogen compound is bis(chloromethyl) etHer.
Claim 11
Dependent Claim 19 words
The process of claim 1 in which said alkali metal is lithium and said polymer is a polymeric butadiene.
Claim 12
Dependent Claim 13 words
The process of claim 12 in which said active-halogen compound is 1,4-bis(chloromethyl) benzene.
Claim 13
Dependent Claim 13 words
The process of claim 12 in which said active-halogen compound is bis(chloromethyl) ether.
Claim 14
Dependent Claim 22 words
The process of claim 12 in which said polymeric butadiene is a butadiene-styrene copolymer having 5-50 percent by weight styrene copolymerized therein.
Claim 15
Dependent Claim 12 words
The process of claim 12 in which said polymeric butadiene is polybutadiene.
Claim 16
Dependent Claim 11 words
The process of claim 1 in which said polymer is polyisoprene.
Claim 17
Dependent Claim 10 words
A polymer produced according to the process of claim 1.

References Cited (Backward Citations)

US3078254A Cited
US3280084A Cited
GB1025295A Cited
US3231635A Cited
US3435011A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-04-02 1976-10-02 1977-04-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-04-02 1980-10-02 1981-04-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-04-02 1984-10-02 1985-04-03 $7700.00 Window Closed / Lapsed

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