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US4057518A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for the manufacture of heat resistant multicellular materials

Assignee: Rhone Poulenc Industries SA
•
Filing: 1975-04-17
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Granted: 1977-11-08
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Expires: 1995-04-17
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Abstract

Abstract Multicellular materials having excellent heat-resistance are provided by preparing granules of 1. a prepolymer obtained from: A. a product containing an imide group, which is A. a bis-imide of the formula: ##STR1## in which D represents a radical of the formula: ##STR2## WHEREIN Y represents H, CH 3 or Cl, m is 0 or 1, and A represents a divalent organic radical containing 2 to 30 carbon atoms, or B. a mixture comprising a bis-imide of formula (I) and a mono-imide of the formula: ##STR3## in which D is as defined above and R represents a hydrogen atom or a monovalent organic radical containing 1 to 20 carbon atoms, and B. an amine product which is A. one or more polyamines containing from 2 to 5 primary or secondary amino groups, at least one of these groups being primary, or B. a mixture comprising one or more polyamines as defined under a) and one or more primary and/or secondary monoamines and/or one or more secondary polyamines, 2. a pore-forming agent and 3. a cell-forming agent, the degree of expansion (as hereinbefore defined) of which is a maximum of 90%, placing these granules in a mould, and effecting complete expansion and thermo-setting of the polymer by heating.

Inventors

  • 👤 Rene Angleraud
  • 👤 Pierre Ledru

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 19:50
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/16; C08J9/04; C08J2379/00; C08J2379/04; C08J2379/08

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 37 words
Process for the manufacture of a multicellular material which comprises preparing pre-expanded granules of: 1. a prepolymer which is a product of reaction of N,N'-4,4'-diphenylmethane-bis-maleimide and 4,4'-diaminodiphenylmethane, the ratio ##EQU3## being from about 1 to about 5;
Claim 2
Dependent Claim 37 words
Process for the manufacture of a multicellular material which comprises preparing pre-expanded granules of: 1. a prepolymer which is a product of reaction of N,N'-4,4'-diphenylmethane-bis-maleimide and 4,4'-diaminodiphenylmethane, the ratio ##EQU3## being from about 1 to about 5;
Claim 3
Dependent Claim 32 words
a flowing agent; and 3. a cell-control agent; the degree of expansion of which is a maximum of 90%, placing these granules in a mould and effecting complete expansion and thermo-setting of
Claim 4
Dependent Claim 32 words
a flowing agent; and 3. a cell-control agent; the degree of expansion of which is a maximum of 90%, placing these granules in a mould and effecting complete expansion and thermo-setting of
Claim 5
Dependent Claim 33 words
the polymer by heating. 2. Process according to claim 1 in which the flowing agent has a decomposition temperature which is at least 20° C higher than the softening point of the prepolymer.
Claim 6
Dependent Claim 24 words
Process according to claim 1 in which the flowing agent is present in an amount from 0.1 to 10% by weight of the prepolymer.
Claim 7
Dependent Claim 18 words
Process according to claim 1, in which the cell-control agent is a cationic, non-ionic or anionic surface-active agent.
Claim 8
Dependent Claim 23 words
Process according to claim 1 in which the cell-control agent is present in an amount up to 5% by weight of the prepolymer.
Claim 9
Dependent Claim 18 words
Process according to claim 1 in which the granules have a degree of expansion of 60 to 85%.
Claim 10
Dependent Claim 23 words
Process according to claim 1 in which the heating is carried out at 150° to 230° C for 5 minutes to 5 hours.

References Cited (Backward Citations)

US3249561A Cited
US3310506A Cited
US3483144A Cited
US3669930A Cited
US3878172A Cited
US3740378A Cited
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US3761430A Cited
USB317080I5 Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-11-07 1981-05-09 1981-11-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-11-07 1985-05-09 1985-11-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-11-07 1989-05-09 1989-11-08 $7700.00 Window Closed / Lapsed

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