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US4081497A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for producing a high impact polystyrene

Assignee: Idemitsu Petrochemical Co Ltd
•
Filing: 1976-07-08
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Granted: 1978-03-28
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Expires: 1996-07-08
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Abstract

Abstract In the method for producing a high impact polystyrene from a monomer of styrene or/and its derivative and a rubbery polymer as reactants, an improvement is provided which comprises passing said reactants through a tubular reactor having parts where the passage way of flow of said reactants is constricted, while keeping said reactants in a laminar flow as much as possible in the parts other than said parts, in a first stage polymerization to prepare a reacted mixture containing a prepolymer until the conversion of monomer to polymer becomes 10 to 60%, and subjecting the resulting reacted mixture to a second stage polymerization in the state where almost no shearing is exerted thereupon. The shearing during said first stage polymerization can be uniformly carried out. The resulting product has superior high impact properties.

Inventors

  • 👤 Ichiro Tokumitsu
  • 👤 Hideo Konuma
  • 👤 Shigeaki Mochizuki
  • 👤 Yoshio Okada
  • 👤 Hiroshi Yasumoto
  • 👤 Isao Yoshihiro

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 22:19
CPC Classifications
C; C08; C08F; C08F291/00; C08F291/02

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 145 words
A method for producing a high-impact polystyrene from reactants that include (I) at least one monomer selected from the group consisting of styrene, halogenated styrenes and alkyl styrenes, and (II) a rubbery polymer, the improvement which comprises (a) in a first stage passing said reactants into a tubular reaction zone, (1) constricting the flow of said reactants in at least one portion of said tubular reaction zone so as to create shearing conditions in each such portion while maintaining laminar flow as much as possible in the unconstricted remainder of said tubular reaction zone, and (2) forming a prepolymer in said first stage by converting 10 - 60% of the monomers to polymers in said tubular reaction zone, (b) in a second stage completing the polymerization of the reaction mixture resulting from said first stage in a polymerization zone wherein there is essentially no shearing.
Claim 2
Independent Claim 145 words
A method for producing a high-impact polystyrene from reactants that include (I) at least one monomer selected from the group consisting of styrene, halogenated styrenes and alkyl styrenes, and (II) a rubbery polymer, the improvement which comprises (a) in a first stage passing said reactants into a tubular reaction zone, (1) constricting the flow of said reactants in at least one portion of said tubular reaction zone so as to create shearing conditions in each such portion while maintaining laminar flow as much as possible in the unconstricted remainder of said tubular reaction zone, and (2) forming a prepolymer in said first stage by converting 10 - 60% of the monomers to polymers in said tubular reaction zone, (b) in a second stage completing the polymerization of the reaction mixture resulting from said first stage in a polymerization zone wherein there is essentially no shearing.
Claim 3
Dependent Claim 26 words
A method according to claim 1, wherein the prepolymer is formed by converting 20 - 40% of the monomers to polymers in said tubular reaction zone.
Claim 4
Dependent Claim 29 words
The method of claim 1 wherein each of said constricted portions provides a pressure drop of at least 1.5 Kg/cm 2 to the reactants passing through said first stage.
Claim 5
Dependent Claim 11 words
The method of claim 1 wherein constriction is effected with valves.
Claim 6
Dependent Claim 13 words
The method of claim 1 wherein constriction is effected by means of orifices.
Claim 7
Dependent Claim 12 words
The method of claim 1 wherein constriction is effected with static mixers.
Claim 8
Dependent Claim 14 words
The method of claim 1 wherein constriction is effected by means of packed zones.

References Cited (Backward Citations)

US3052664A Cited
US3054783A Cited
US3451986A Cited
US3595846A Cited
US3679651A Cited
US3980628A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-03-27 1981-09-26 1982-03-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-03-27 1985-09-26 1986-03-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-03-27 1989-09-26 1990-03-28 $7700.00 Window Closed / Lapsed

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