US4996101A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Processible polyimide blends
Assignee: Lockheed Martin Corp
•
Filing: 1988-08-08
•
Granted: 1991-02-26
•
Expires: 2008-08-08
Abstract
Abstract Semi-interpenetrating polymer networks having improved processibility and compatibility are prepared by combining a linear polymer comprised of a thermoplastic polyisoimide and a short chain thermosetting polymer in the form of a cross-linkable oligomer comprised of a thermosetting imide or isoimide oligomer containing unsaturated terminal groups, e.g., an acetylene-, a maleimide-, a nadimide- or a benzocyclobutene-terminated imide or isoimide oligomer. In the resulting blend at least one of the diamine and dianhydride moieties of the structural backbone unit of the polyisoimide and of the cross-linkable oligomer are the same, and preferably both of the components of the blend have the same structural backbone unit. An example of a preferred semi-interpenetrating polymer network is the combination of (1) the polyisoimide produced by reaction of benzophenonetetracarboxylic dianhydride (BTDA) with 1,3-bis (3-amino-phenoxy)benzene (APB) to form the polyamic acid precursor, followed by cyclodehydration thereof, and (2) the acetylene-terminated isoimide oligomer containing BTDA-APB backbone units and marketed as Thermid IP-600 by National Starch Company. Upon curing such semi-interpenetrating network or blend, a polymer having high toughness and high modulus is obtained.
Inventors
- 👤 Abraham L. Landis
- 👤 Kreisler S. Y. Lau
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 04:12
CPC Classifications
C; C09; C09J; C09J179/00; C09J179/04; C09J179/08; C08; C08L; C08L79/00; C08L79/04; C08L79/08; Y; Y10; Y10S; Y10S525/00; Y10S525/903; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2918; Y10T428/2933; Y10T428/2964; Y10T428/30; Y10T428/31504; Y10T428/31721; Y10T442/00; Y10T442/20; Y10T442/2738
Claims Analysis
Total Claims: 45
Claim 1
Independent Claim
52 words
In the process of making a semi-interpenetrating polyimide network wherein a linear polymer is combined and blended with ac ross-linkable oligomer and the resulting blend is cured, the improvement wherein the linear polymer comprises a thermoplastic polyisoimide and the cross-linkable oligomer comprises a thermosetting imide or isoimide oligomer having unsaturated terminal groups.
Claim 2
Dependent Claim
52 words
In the process of making a semi-interpenetrating polyimide network wherein a linear polymer is combined and blended with ac ross-linkable oligomer and the resulting blend is cured, the improvement wherein the linear polymer comprises a thermoplastic polyisoimide and the cross-linkable oligomer comprises a thermosetting imide or isoimide oligomer having unsaturated terminal groups.
Claim 3
Dependent Claim
28 words
The process of claim 1, wherein at least one of the moieties of the structural backbone unit of tho polyisoimide and of the thermosetting oligomer are the same.
Claim 4
Dependent Claim
18 words
The process of claim 1, wherein said polyisoimide and said thermosetting oligomer have the same structural backbone unit.
Claim 5
Dependent Claim
12 words
The process of claim 1, wherein said thermoplastic polyisoimide contains imide units.
Claim 6
Dependent Claim
15 words
The process of claim 4, wherein said polyisoimide has a major proportion of isoimide units.
Claim 7
Dependent Claim
16 words
The process of claim 1, wherein said thermosetting oligomer having unsaturated terminal groups is an isoimide.
Claim 8
Dependent Claim
25 words
The process of claim 1, wherein said thermosetting oligomer is selected from the group consisting of acetylene-terminated, maleimide-terminated, nadimide-terminated and benzocyclobutene-terminated imide and isoimide oligomers.
Claim 9
Dependent Claim
11 words
The process of claim 7, wherein said thermosetting is an isoimide.
Claim 10
Dependent Claim
25 words
The process of claim 1, wherein the polyisoimide has following structural formula: ##STR9## wherein n is an integer of from about 30 to about 400.
Claim 11
Dependent Claim
30 words
The process of claim 1, wherein the thermosetting oligomer is an acetylene-terminated isoimide oligomer having the following structural formula: ##STR10## where m is an integer of 1 to about 10.
Claim 12
Dependent Claim
52 words
The process of claim 1, wherein the polyisoimide has the following structural formula: ##STR11## wherein n is an integer of from about 30 to about 400, and wherein the thermosetting oligomer is an acetylene-terminated isoimide oligomer having the following structural formula: ##STR12## where m is an integer of 1 to about 4.
Claim 13
Dependent Claim
34 words
The process of claim 1, wherein the amount of the polyisoimide ranges from about 10 to about 90%, and the amount of the thermosetting oligomer ranges from about 90 to about 10%, by weight.
Claim 14
Dependent Claim
34 words
The process of claim 11, wherein the amount of the polyisoimide ranges from about 25 to about 75%, and the amount of the thermosetting oligomer ranges from about 75 to about 25%, by weight.
Claim 15
Dependent Claim
52 words
In a semi-interpenetrating polymer network formed by curing a linear polymer combined with a cross-linkable oligomer, each of which is curable in the presence of the other, the improvement wherein the linear polymer comprises a thermoplastic polyisoimide and the cross-linkable oligomer comprises a thermosetting imide or isoimide oligomer having unsaturated terminal groups.
Claim 16
Dependent Claim
52 words
In a semi-interpenetrating polymer network formed by curing a linear polymer combined with a cross-linkable oligomer, each of which is curable in the presence of the other, the improvement wherein the linear polymer comprises a thermoplastic polyisoimide and the cross-linkable oligomer comprises a thermosetting imide or isoimide oligomer having unsaturated terminal groups.
Claim 17
Dependent Claim
29 words
The semi-interpenetrating polymer network of claim 14, wherein at least one of the moieties of the structural backbone unit of the polyisoimide and the thermosetting oligomer are the same.
Claim 18
Dependent Claim
20 words
The semi-interpenetrating polymer network of claim 14, wherein said polyisoimide and said thermosetting oligomer have the same structural backbone unit.
Claim 19
Dependent Claim
17 words
The semi-interpenetrating polymer network of claim 14, wherein said polyisoimide has a major proportion of isoimide units.
Claim 20
Dependent Claim
14 words
The semi-interpenetrating polymer network of claim 14, wherein said thermosetting oligomer is an isoimide.
Claim 21
Dependent Claim
14 words
The semi-interpenetrating polymer network of claim 17, wherein said thermosetting oligomer is an isoimide.
Claim 22
Dependent Claim
53 words
The semi-interpenetrating polymer network of claim 14, wherein the polyisoimide has the following structural formula: ##STR13## wherein n is an integer of from about 30 to about 400, and wherein the thermosetting oligomer is acetylene-terminated isoimide oligomer having the following structural formula: ##STR14## where m is an integer of 1 to about 4.
Claim 23
Dependent Claim
44 words
The semi-interpenetrating polymer network of claim 14, wherein the polyisoimide has the following structural formula: ##STR15## wherein n is an integer of from about 30 to about 400, and wherein the thermosetting oligomer is an acetylene-terminated isoimide oligomer having the following structural formula: ##STR16##
Claim 24
Dependent Claim
36 words
The semi-interpenetrating polymer network of claim 14, wherein the amount of the polyisoimide ranges from about 10 to about 90%, and the amount of the thermosetting oligomer ranges from about 90 to about 10%, by weight.
Claim 25
Dependent Claim
36 words
The semi-interpenetrating polymer network of claim 14, wherein the amount of the polyisoimide ranges from about 25 to about 75%, and the amount of the thermosetting oligomer ranges from about 75 to about 25%, by weight.
Claim 26
Dependent Claim
23 words
The interpenetrating polymer network of claim 20, employing about 50% of said polyisoimide and about 50% of said acetylene-terminated isoimide oligomer, by weight.
Claim 27
Dependent Claim
60 words
A two component resin system which upon curing forms a semi-interpenetrating polymer network having toughness and good compressive modulus, which comprises a mixture of effective amounts sufficient to form said polymer network upon curing, of a thermoplastic linear polymer having isoimide groups and a short chain thermosetting imide or isoimide oligomer having unsaturated terminal groups capable of curing by homopolymerization.
Claim 28
Dependent Claim
60 words
A two component resin system which upon curing forms a semi-interpenetrating polymer network having toughness and good compressive modulus, which comprises a mixture of effective amounts sufficient to form said polymer network upon curing, of a thermoplastic linear polymer having isoimide groups and a short chain thermosetting imide or isoimide oligomer having unsaturated terminal groups capable of curing by homopolymerization.
Claim 29
Dependent Claim
28 words
The resin system of claim 25, wherein said polyisoimide has a major proportion of isoimide units, and wherein said thermosetting oligomer having unsaturated terminal groups is an isoimide.
Claim 30
Dependent Claim
26 words
The resin system of claim 25, wherein said thermosetting oligomer is selected from the group consisting of acetylene-terminated, maleimide-terminated, nadimide-terminated and benzocyclobutene-terminated imide and isoimide oligomers.
Claim 31
Dependent Claim
35 words
The resin system of claim 25, wherein the amount of the polyisoimide ranges from about 10 to about 90%, and the amount of the thermosetting oligomer ranges from about 90 to about 10%, by weight.
Claim 32
Dependent Claim
35 words
The resin system of claim 27, wherein the amount of the polyisoimide ranges from about 25 to about 75%, and the amount of the thermosetting oligomer ranges from about 75 to about 25%, by weight.
Claim 33
Dependent Claim
54 words
In a composite comprising resin-impregnated fabric, the improvement wherein said resin comprises a semi-interpenetrating polymer network, said semi-interpenetrating polymer network formed by curing a linear polymer combined with a cross-linkable oligomer, wherein said linear polymer comprises a thermoplastic polyisoimide and said cross-linkable oligomer comprises a thermosetting imide or isoimide oligomer having unsaturated terminal groups.
Claim 34
Dependent Claim
54 words
In a composite comprising resin-impregnated fabric, the improvement wherein said resin comprises a semi-interpenetrating polymer network, said semi-interpenetrating polymer network formed by curing a linear polymer combined with a cross-linkable oligomer, wherein said linear polymer comprises a thermoplastic polyisoimide and said cross-linkable oligomer comprises a thermosetting imide or isoimide oligomer having unsaturated terminal groups.
Claim 35
Dependent Claim
51 words
An adhesive comprising a solution of a semi-interpenetrating polymer network and a solvent, said semi-interpenetrating polymer network formed by curing a linear polymer combined with a cross-linkable oligomer, wherein said linear polymer comprises a thermoplastic polyisoimide and said cross-linkable oligomer comprises a thermosetting imide or isoimide oligomer having unsaturated terminal groups.
Claim 36
Dependent Claim
51 words
An adhesive comprising a solution of a semi-interpenetrating polymer network and a solvent, said semi-interpenetrating polymer network formed by curing a linear polymer combined with a cross-linkable oligomer, wherein said linear polymer comprises a thermoplastic polyisoimide and said cross-linkable oligomer comprises a thermosetting imide or isoimide oligomer having unsaturated terminal groups.
Claim 37
Dependent Claim
15 words
The process of claim 1, wherein said unsaturated terminal groups comprise ethylenic or acetylenic groups.
Claim 38
Dependent Claim
17 words
The semi-interpenetrating polymer network of claim 14, wherein said unsaturated terminal groups comprise ethylenic or acetylenic groups.
Claim 39
Dependent Claim
14 words
The composite of claim 30, wherein said cross-linkable oligomer is an acetylene-terminated isoimide oligomer.
Claim 40
Dependent Claim
14 words
The adhesive of claim 31, wherein said cross-linkable oligomer is an acetylene-terminated isoimide oligomer.
Claim 41
Dependent Claim
55 words
A process for making a semi-interpenetrating polymer network which comprises heating and curing a mixture of a thermoplastic polyisoimide and a cross-linkable thermosetting imide or isoimide oligomer having unsaturated terminal groups, and converting said polyisoimide to a polyimide and homopolymerizing said imide or isoimide oligomer having unsaturated terminal groups, to form said semi-interpenetrating polymer network.
Claim 42
Dependent Claim
55 words
A process for making a semi-interpenetrating polymer network which comprises heating and curing a mixture of a thermoplastic polyisoimide and a cross-linkable thermosetting imide or isoimide oligomer having unsaturated terminal groups, and converting said polyisoimide to a polyimide and homopolymerizing said imide or isoimide oligomer having unsaturated terminal groups, to form said semi-interpenetrating polymer network.
Claim 43
Dependent Claim
16 words
The process of claim 36, wherein said thermosetting oligomer having unsaturated terminal groups is an isoimide.
Claim 44
Dependent Claim
25 words
The process of claim 36, wherein said thermosetting oligomer is selected from the group consisting of acetylene-terminated, maleimide-terminated, nadimide-terminated and benzocyclobutene-terminated imide and isoimide oligomers.
Claim 45
Dependent Claim
34 words
The process of claim 36, wherein the amount of the polyisoimide ranges from about 10 to about 90%, and the amount of the thermosetting oligomer ranges from about 90 to about 10%, by weight.
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) | 1994-02-25 | 1994-08-27 | 1995-02-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-02-25 | 1998-08-27 | 1999-02-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-02-25 | 2002-08-27 | 2003-02-26 | $7700.00 | Window Closed / Lapsed |