← Back to Patent Explorer
US3775392A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for polymerizing conjugated dienes

Assignee: Bridgestone Firestone Inc
•
Filing: 1971-09-07
•
Granted: 1973-11-27
•
Expires: 1991-09-07
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract CONJUGATED DIENES ARE POLYMERIZED BY A NEW CATALYST SYSTEM WHICH PERMITS CONTROL OF THE MOLECULAR WEIGHT AND GIVES A MORE EASILY PROCESSED PRODUCT. THIS CATALYST SYSTEM COMPRISES (1) A SODIUM HYDROCARBON COMPOUND HAVING 1-10 CARBON ATOMS IN WHICH THE HYDROCARBON PORTION IS A PRIMARY, SECONDARY OR TERTIARY ALKYL RADICAL, AND (2) A POTASSIUM TERTIARY ALKOXIDE OF 4-10 CARBON ATOMS. THE DIENE POLYMERS PRODUCED BY THIS PROCESS HAVE CONTROLLABLE MOLECULAR WEIGHTS IN THE RANGE OF 25,000 TO 1,000,000, PREFERABLY 100,000-500,000, BROAD MOLECULAR WEIGHT DISTRIBUTION, GLASS TRANSITION TEMPERATURES HIGHER THAN NORMALLY OBTAINED, HIGH DEGREE OF BRANCHING AND ARE MORE EASILY PROCESSED IN THE PRODUCTION OF RUBBER AND OTHER COMPOSITIONS FOR COMMERCIAL USE.

Inventors

  • 👤 Chun Cheng Tai
  • 👤 A Halasa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 12:59
CPC Classifications
C; C08; C08F; C08F36/00; C08F36/02; C08F36/04

Claims Analysis

Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.

References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-11-26 1977-05-28 1977-11-27 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-11-26 1981-05-28 1981-11-27 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-11-26 1985-05-28 1985-11-27 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag