US5371111A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of reprocessing cured polysulfide and/or mercaptan elastomers
Assignee: GEA Group AG
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Filing: 1992-12-21
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Granted: 1994-12-06
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Expires: 2012-12-21
Abstract
Abstract The method of reprocessing cured polysulfide and polymercaptan elastomers includes reacting an 0.5 to 400 percent-by-weight portion of a polysulfide and/or polymercaptan elastomer with at least one liquid di- or polymercapto compound, with a plasticizer and with a filling material and with an binding agent to form a polysulfide sealing material-base component. Then a polysulfide sealing material curing agent is added to the polysulfide sealing material-base component to form the reprocessed cured polysulfide sealing material with a Shore-A-Hardeness>40 and a tensile strength>1 MPa.
Inventors
- 👤 Gerfried Unger
- 👤 Ralph-Josef Hecktor
- 👤 Reiner Theobald
- 👤 Franz Specht
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 08:36
CPC Classifications
C; C08; C08J; C08J11/00; C08J11/04; C08J11/10; C08J11/18; C08J11/28; C08J2381/00; C08J2381/04; Y; Y02; Y02W; Y02W30/00; Y02W30/50; Y02W30/62
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
125 words
A method of reprocessing cured polysulfide and polymercaptan elastomers, said method comprising the steps of: a. reacting at temperatures from 0° to 100° C. an 0.5 to 400 percent-by-weight portion of a cured solid elastomer selected from the group consisting of cured solid polysulfide elastomers, cured solid polymercaptan elastomers and mixtures thereof with at least one liquid compound having a molecular weight from 500 to 8000 g/mole and selected from the group consisting of dimercapto compounds and polymercapto compounds, a plasticizer, a filling material and a binding agent to form liquid to pasty mercapto-terminated prepolymers; and b. then adding a curing paste to said liquid-to-pasty mercapto-terminated prepolymers to form a reprocessed cured polysulfide sealing material with a Shore-A-Hardeness >40 and a tensile strength >1 MPa.
Claim 2
Independent Claim
125 words
A method of reprocessing cured polysulfide and polymercaptan elastomers, said method comprising the steps of: a. reacting at temperatures from 0° to 100° C. an 0.5 to 400 percent-by-weight portion of a cured solid elastomer selected from the group consisting of cured solid polysulfide elastomers, cured solid polymercaptan elastomers and mixtures thereof with at least one liquid compound having a molecular weight from 500 to 8000 g/mole and selected from the group consisting of dimercapto compounds and polymercapto compounds, a plasticizer, a filling material and a binding agent to form liquid to pasty mercapto-terminated prepolymers; and b. then adding a curing paste to said liquid-to-pasty mercapto-terminated prepolymers to form a reprocessed cured polysulfide sealing material with a Shore-A-Hardeness >40 and a tensile strength >1 MPa.
Claim 3
Dependent Claim
19 words
A method as defined in claim 1, wherein the reacting takes place in the presence of a basic compound.
Claim 4
Dependent Claim
71 words
A method as defined in claim 1, wherein the reacting takes place at a temperature from 70° to 80° C. in the presence of one mole of an amino compound and the cured solid elastomer reacted during the reacting is present in an amount of from 0.5 to 20% by weight and said at least one liquid compound has a prepolymer structure which is the same as said cured solid elastomer.
Claim 5
Dependent Claim
13 words
A method as defined in claim 3, wherein the amino compound is trimethylamine.
Claim 6
Dependent Claim
22 words
A method as defined in claim 1, further comprising obtaining said portion of said cured solid elastomer by collecting elastomeric waste materials.
Claim 7
Dependent Claim
16 words
A method as defined in claim 1, wherein said cured solid elastomer contains impurities and additives.
Claim 8
Dependent Claim
23 words
A method as defined in claim 2, wherein said basic compound is selected from the group consisting of alkali alcoholates, amines and amides.
Claim 9
Dependent Claim
17 words
A method as defined in claim 1, wherein said curing paste is a manganese dioxide-based curing paste.
References Cited (Backward Citations)
US4623711A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-12-05 | 1998-06-06 | 1998-12-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-12-05 | 2002-06-06 | 2002-12-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-12-05 | 2006-06-06 | 2006-12-06 | $7700.00 | Window Closed / Lapsed |