US4395306A
Expired / Lapsed
US
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Method for preparing fibrous mats from a fibrous suspension
Assignee: Dow Chemical Co
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Filing: 1982-01-08
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Granted: 1983-07-26
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Expires: 2002-01-08
Abstract
Abstract Nonwoven mats or sheets having improved tensile strengths are prepared from a fibrous suspension of synthetic fibers thickened with a synthetic, addition polymer bearing pendant carboxamide groups and a cross-linking agent for the polymeric thickener. For example, a fibrous suspension comprising glass fibers, a polymer of acrylamide and a water-soluble hypohalite can be employed to prepare strong, glass fiber mats useful as effective reinforcement for roofing shingles.
Inventors
- 👤 George R. Killat
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 11:37
CPC Classifications
D; D21; D21H; D21H13/00; D21H13/36; D21H13/38; D21H13/40; C; C04; C04B; C04B26/00; C04B26/02; C04B26/04; D21F; D21F11/00; D21F11/004; D21H17/00; D21H17/20; D21H17/33; D21H17/34; D21H17/37; D21H17/375; H; H01; H01M; H01M50/00; H01M50/10; H01M50/116; H01M50/117; H01M50/121; H01M50/122; H01M50/131; Y; Y02; Y02E; Y02E60/00; Y02E60/10; Y10; Y10T; Y10T442/00; Y10T442/20; Y10T442/2926; Y10T442/2992
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
97 words
An improved method for preparing a fibrous mat or sheet by depositing a layer of a thickened fibrous suspension of synthetic fibers and an aqueous suspending medium thickened by a carboxamide synthetic addition polymer on a support, removing substantially all of said suspending medium to leave a fibrous mat with a residuum of a minor amount of said carboxamide polymer on the fibers, the improvement wherein said carboxamide polymer is reacted with a hypohalite to form a reaction product in said suspending medium, which as said residuum will cross-link to provide a fibrous mat of improved strength.
Claim 2
Dependent Claim
97 words
An improved method for preparing a fibrous mat or sheet by depositing a layer of a thickened fibrous suspension of synthetic fibers and an aqueous suspending medium thickened by a carboxamide synthetic addition polymer on a support, removing substantially all of said suspending medium to leave a fibrous mat with a residuum of a minor amount of said carboxamide polymer on the fibers, the improvement wherein said carboxamide polymer is reacted with a hypohalite to form a reaction product in said suspending medium, which as said residuum will cross-link to provide a fibrous mat of improved strength.
Claim 3
Dependent Claim
26 words
The improved method of claim 1 wherein the synthetic addition polymer is a water-soluble polymer of an ethylenically unsaturated carboxamide or an N-substituted ethylenically unsaturated carboxamide.
Claim 4
Dependent Claim
29 words
The improved method of claim 1 wherein the synthetic, addition polymer is derived from an ethylenically unsaturated carboxamide and the cross-linking agent is an ammonium or alkali metal hypohalite.
Claim 5
Dependent Claim
29 words
The improved method of claim 1 wherein the cross-linking agent is employed in an amount of from about 0.01 to about 0.5 equivalent per equivalent of the polymeric thickener.
Claim 6
Dependent Claim
17 words
The improved method of claim 2 wherein the N-substituted ethylenically unsaturated carboxamide is an N-substituted (N', N'-dialkylaminoalkyl)acrylamide.
Claim 7
Dependent Claim
48 words
The improved method of claim 5 wherein at least about 50 mole percent of the polymerized monomer units comprising the polymeric thickener bear pendant groups which are N-substituted carboxamides of the formula: ##STR3## wherein R is individually hydrogen, alkyl, aminoalkyl or dialkylaminomethyl provided both R's are not hydrogen.
Claim 8
Dependent Claim
13 words
The improved method of claim 6 wherein each R is a dialkylaminomethyl group.
Claim 9
Dependent Claim
11 words
The improved method of claim 7 wherein each R is dimethylaminomethyl.
Claim 10
Dependent Claim
37 words
The improved method of claim 8 wherein the cross-linking agent is an ammonium or alkali metal hypochlorite and is employed in an amount of from about 0.01 to about 0.5 equivalent per equivalent of the polymeric thickener.
Claim 11
Dependent Claim
12 words
The method of claim 9 wherein the cross-linking agent is sodium hypochlorite.
Claim 12
Dependent Claim
58 words
The improved method of claim 1 wherein the fibrous mat or sheet is prepared from a thickened, fibrous suspension comprising synthetic fibers and an aqueous suspending medium thickened by a carboxamide polymer which suspension further comprises a cross-linking agent for the polymeric thickener, the cross-linking agent being in an amount which does not cause precipitation of the polymer.
Claim 13
Dependent Claim
40 words
The improved method of claim 1 wherein the fibers are contacted with the cross-linking agent for the polymeric thickener by spraying an aqueous solution of the cross-linking agent on the fibrous mat or sheet prepared from the thickened, fibrous suspension.
Claim 14
Dependent Claim
18 words
The improved method of claim 12 which further comprises applying a binder to the fibrous mat or sheet.
Claim 15
Dependent Claim
13 words
The improved method of claim 1 wherein said synthetic fibers are glass fibers.
Claim 16
Dependent Claim
47 words
A thickened, fibrous suspension comprising an aqueous suspension of synthetic fibers thickened with a synthetic carboxamide polymer and an amount of a water-soluble hypohalite cross-linking agent for the polymeric thickener such that a fibrous mat or sheet prepared from the thickened, fibrous suspension exhibit increased tensile strength.
Claim 17
Dependent Claim
47 words
A thickened, fibrous suspension comprising an aqueous suspension of synthetic fibers thickened with a synthetic carboxamide polymer and an amount of a water-soluble hypohalite cross-linking agent for the polymeric thickener such that a fibrous mat or sheet prepared from the thickened, fibrous suspension exhibit increased tensile strength.
Claim 18
Dependent Claim
11 words
The suspension of claim 15 wherein said fibers are glass fibers.
References Cited (Backward Citations)
US3391057A
Cited
US3630831A
Cited
US3752733A
Cited
US3772142A
Cited
US3988503A
Cited
US3976824A
Cited
US4049491A
Cited
US4081319A
Cited
US4199643A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-07-25 | 1987-01-24 | 1987-07-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-07-25 | 1991-01-24 | 1991-07-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-07-25 | 1995-01-24 | 1995-07-26 | $7700.00 | Window Closed / Lapsed |