US5326489A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrorheological fluids
Assignee: Nippon Shokubai Co Ltd
•
Filing: 1992-11-27
•
Granted: 1994-07-05
•
Expires: 2012-11-27
Abstract
Abstract An electrorheological fluid composition comprising a dispersion of disperse-phase particles formed of a sulfonated polymer possessing aromatic rings substituted with sulfonic acid groups in an electrically non-conducting oil which electrorheological fluid is characterized by the fact that the number of sulfonic acid groups in said sulfonated polymer forming said disperse-phase particles exceeds the number of aromatic rings present in said sulfonated polymer.
Inventors
- 👤 Yoshinobu Asako
- 👤 Satoru Ono
- 👤 Minoru Aoki
- 👤 Izuho Okada
- 👤 Minoru Kobayashi
- 👤 Ryuji Aizawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 10:38
CPC Classifications
C; C10; C10M; C10M171/00; C10M171/001; C08; C08F; C08F212/00; C08F212/02; C08F212/04; C08F212/06; C08F212/08; C08F8/00; C08F8/34; C08F8/36; C08F8/44; C08F2800/00; C08F2800/20
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
151 words
An electrorheological fluid composition comprising a dispersion of disperse-phase particles formed of a sulfonated polymer possessing aromatic rings substituted with sulfonic acid groups in an electrically non-conducting oil which electrorheological fluid is characterized by the fact that the number of sulfonic acid groups in said sulfonated polymer forming said disperse-phase particles exceeds the number of aromatic rings present in said sulfonated polymer, the ratio of said disperse-phase particles to said electrically non-conducting oil is 50-500 to 100 in parts by weight, said disperse-phase particles having an average particle diameter in the range of from 0.1 to 100 μm, the ratio between the number of sulfonic acid groups to those of the aromatic groups being 105 to 200 per 100 aromatic rings present in the sulfonated polymer and the water content in the dispersed phase is 1.0 to 10 parts by weight, based on 100 parts by weight of the sulfonated polymer.
Claim 2
Dependent Claim
151 words
An electrorheological fluid composition comprising a dispersion of disperse-phase particles formed of a sulfonated polymer possessing aromatic rings substituted with sulfonic acid groups in an electrically non-conducting oil which electrorheological fluid is characterized by the fact that the number of sulfonic acid groups in said sulfonated polymer forming said disperse-phase particles exceeds the number of aromatic rings present in said sulfonated polymer, the ratio of said disperse-phase particles to said electrically non-conducting oil is 50-500 to 100 in parts by weight, said disperse-phase particles having an average particle diameter in the range of from 0.1 to 100 μm, the ratio between the number of sulfonic acid groups to those of the aromatic groups being 105 to 200 per 100 aromatic rings present in the sulfonated polymer and the water content in the dispersed phase is 1.0 to 10 parts by weight, based on 100 parts by weight of the sulfonated polymer.
Claim 3
Dependent Claim
53 words
An electrorheological fluid composition according to claim 1, wherein said sulfonated polymer is obtained by sulfonation of the aromatic rings present in (I) a cross-linked polymer of (A) a monomer mixture having as main components thereof (a) a vinyl aromatic compound and (b) a polyvinyl compound and optionally containing (c) other vinyl compound.
Claim 4
Dependent Claim
44 words
An electrorheological fluid according to claim 2, wherein the proportions of (a) said vinyl aromatic compound and (b) said polyvinyl compound in (A) said monomer mixture are in ranges of from 50.0 to 99.9 mol % and from 50.0 to 0.1 mol %, respectively.
Claim 5
Dependent Claim
65 words
An electrorheological fluid composition according to claim 2, wherein (a) said vinyl aromatic compound comprises a vinyl aromatic compound possessing at least one electron-donating group on the aromatic ring thereof and said vinyl aromatic compound possessing at least one electron-donating group on the aromatic ring thereof accounts for a proportion of not less than 5.0 mol%, based on the amount of (A) said monomer mixture.
Claim 6
Dependent Claim
16 words
An electrorheological fluid composition according to claim 4, wherein said electron-donating group is an alkoxy group.
Claim 7
Dependent Claim
43 words
An electrorheological fluid composition according to claim 2, wherein said sulfonated polymer is obtained by sulfonation of (I) said cross-linked polymer with not less than 600 parts by weight of chlorosulfonic acid, based on 100 parts by weight of (I) said cross-linked polymer.
Claim 8
Dependent Claim
44 words
An electrorheological fluid composition according to claim 6, wherein said sulfonation is carried out by keeping (I) said cross-linked polymer in the presence of chlorosulfonic acid at a temperature of not lower than 70° C. for a period of not less than 30 minutes.
Claim 9
Dependent Claim
76 words
An electrorheological fluid composition according to claim 6, wherein said sulfonation is carried out by keeping (I) said cross-linked polymer in the presence of chlorosulfonic acid at a temperature not lower than -20° C. and lower than 70° C. for a period in the range of from 0.3 to 30 hours and further keeping the resulting reaction mixture at a temperature of not lower than 70° C. for a period of not less than 30 minutes.
Claim 10
Dependent Claim
44 words
An electrorheological fluid composition according to claim 2, wherein said sulfonated polymer is obtained by sulfonation of (I) said cross-linked polymer with not less than 150 parts by weight of fuming sulfuric acid, based on 100 parts by weight of (I) said cross-linked polymer.
Claim 11
Dependent Claim
45 words
An electrotheological fluid composition according to claim 9, wherein said sulfonation is carried out by keeping (I) said cross-linked polymer in the presence of fuming sulfuric acid at a temperature of not lower than 70° C. for a period of not less than 30 minutes.
Claim 12
Dependent Claim
78 words
An electrorheological fluid composition according to claim 9, wherein said sulfonation is carried out by keeping (I) said cross-linked polymer in the presence of fuming sulfuric acid at a temperature of not lower than -20° C. and lower than 70° C. for a period in the range of from 0.3 to 30 hours and further keeping the resulting reaction mixture at a temperature of not lower than 70° C. for a period of not less than 30 minutes.
Claim 13
Dependent Claim
33 words
An electrorheological fluid composition according to claim 2, wherein said sulfonated polymer is obtained by sulfonation of (I) said cross-linked polymer in the presence of a sulfonating agent and a transition metal salt.
Claim 14
Dependent Claim
47 words
An electrorheological fluid composition according to claim 12, wherein said sulfonation is carried out in the presence of a transition metal salt of an amount in the range of from 0.01 to 10 parts by weight, based on 100 parts by weight of (I) said cross-linked polymer.
Claim 15
Dependent Claim
50 words
An electrorheological fluid composition according to claim 13, wherein said sulfonation is carried out by keeping (I) said cross-linked polymer in the presence of a sulfonating agent and a transition metal salt at a tempeature of not lower than 60° C. for a period of not less than 30 minutes.
Claim 16
Dependent Claim
83 words
An electrorheological fluid composition according to claim 13, wherein said sulfonation is carried out by keeping (I) said cross-linked polymer in the presence of a sulfonating agent and a transition metal salt at a tempeature of not lower than -20° C. and lower than 60° C. for a period in the range of from 0.3 to 30 hours and further keeping the resulting reaction mixture at a temperature of not lower than 60° C. for a period of not less than 30 minutes.
Claim 17
Dependent Claim
33 words
An electrorheological fluid composition according to claim 2, wherein said sulfonated polymer is obtained by sulfonation of (I) said cross-linked polymer in the presence of a sulfonating agent and a pentavalent phosphorus compound.
Claim 18
Dependent Claim
44 words
An electrorheological fluid composition according to claim 16, wherein said sulfonation is carried out in the presence of a pentavalent phosphorus compound of an amount of not less than 1.0 part by weight based on 100 parts by weight of (I) said cross-linked polymer.
Claim 19
Dependent Claim
50 words
An electrorheological fluid composition according to claim 17, wherein said sulfonation is carried out by keeping (I) said cross-linked polymer in the presence of a sulfonating agent and a pentavalent phosphorus compound at a temperature of not lower than 60° C. for a period of not less than 30 minutes.
Claim 20
Dependent Claim
83 words
An electrorheological fluid composition according to claim 17, wherein said sulfonation is carried out by keeping (I) said cross-linked polymer in the presence of a sulfonating agent and a pentavalent phosphorus compound at a temperature of not lower than -20° C. and lower than 60° C. for a period in the range of from 0.3 to 30 hours and further keeping the resulting reaction mixture at a temperature of not lower than 60° C. for a period of not less than 30 minutes.
Claim 21
Dependent Claim
36 words
An electrorheological fluid composition according to claim 1, wherein said sulfonated polymer is obtained by mixing particles of a dry sulfonated polymer intermediate with a sulfonating agent and then subjecting the resultant mixture to additional sulfonation.
Claim 22
Dependent Claim
57 words
An electrorheological fluid composition according to claim 20, wherein said sulfonated polymer is obtained by subjecting said dry sulfonated polymer intermediate to additional sulfonation with chlorosulfonic acid and/or fuming sulfuric acid of an amount of not less than 100 parts by weight, based on 100 parts by weight of the particles of said dry sulfonated polymer intermediate.
Claim 23
Dependent Claim
76 words
An electrorheological fluid composition according to claim 20 or claim 21, wherein the particles of said dry sulfonated polymer intermediate are obtained by sulfonating the particles of (I) a cross-linked polymer of (A) a monomer mixture having as main components thereof (a) a vinyl aromatic compound and (b) a polyvinyl compound and optionally containing (c) other vinyl compound with a sulfonating agent, and separating the produced particles from the reaction mixture and drying the separated particles.
Claim 24
Dependent Claim
45 words
An electrorheological fluid composition according to claim 22, wherein the proportions of (a) said vinyl aromatic compound and (b) said polyvinyl compound is (A) said monomer mixture are in ranges of from 50.0 to 99.9 mol % and from 50.0 to 0.1 mol %, respectively.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-07-04 | 1998-01-03 | 1998-07-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-07-04 | 2002-01-03 | 2002-07-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-07-04 | 2006-01-03 | 2006-07-05 | $7700.00 | Window Closed / Lapsed |