EP0196476A2
Expired / Lapsed
EP
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Method for preparing a random-fiber reinforced thermoset polymer composite
Assignee: Dow Chemical Co
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Filing: 1986-03-04
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Granted: —
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Expires: 2006-03-04
Abstract
Abstract A wet-laid processes for the preparation of random-fiber reinforced/thermoset polymer composite mats which include a latent curing agent and/or a coreactant. The mats are subsequently densified and cured into articles of manufacture.
Inventors
- 👤 Larry D. Yats
- 👤 Ritchie A. Wessling
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 09:30
CPC Classifications
D; D21; D21H; D21H13/00; D21H13/10; D21H13/12; D21H13/14; C; C08; C08J; C08J5/00; C08J5/04; C08J5/24; C08J5/241; C08J5/244; C08J5/249; C08L; C08L63/00; D21H13/36; D21H13/38; D21H13/40; D21H17/00; D21H17/20; D21H17/33; D21H17/46; D21H17/47; D21H17/48; D21H17/49; D21H17/52; C08J2363/00
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
148 words
A process for preparing a random-fiber reinforced/thermoset polymer composite comprising the steps of: (a) preparing an aqueous slurry comprising reinforcing fibers, a binder, and a thermoset polymer formulation selected from (i) a solid thermoset polymer; (ii) a solid thermoset polymer and a latent curing agent; and (iii) an aqueous dispersion of the solid thermoset polymer; (b) destabilizing the solids in the slurry with a polymeric flocculant having a charge which is opposite to the charge of said binder, and dewatering the aqueous slurry; (c) collecting the solids in the form of a mat; (d) drying the mat under conditions such that said thermoset polymer remains in a heat formable state; (e) saturating the mat prepared from (a)i and (a)iii with a liquid coreactant; and (f) subjecting said mat to an elevated temper- . ature and pressure sufficient to curb said polymer to form said mat into said composite.
Claim 2
Dependent Claim
148 words
A process for preparing a random-fiber reinforced/thermoset polymer composite comprising the steps of: (a) preparing an aqueous slurry comprising reinforcing fibers, a binder, and a thermoset polymer formulation selected from (i) a solid thermoset polymer; (ii) a solid thermoset polymer and a latent curing agent; and (iii) an aqueous dispersion of the solid thermoset polymer; (b) destabilizing the solids in the slurry with a polymeric flocculant having a charge which is opposite to the charge of said binder, and dewatering the aqueous slurry; (c) collecting the solids in the form of a mat; (d) drying the mat under conditions such that said thermoset polymer remains in a heat formable state; (e) saturating the mat prepared from (a)i and (a)iii with a liquid coreactant; and (f) subjecting said mat to an elevated temper- . ature and pressure sufficient to curb said polymer to form said mat into said composite.
Claim 3
Dependent Claim
54 words
The process of Claim 1, wherein said reinforcing fibers are selected from glass fibers, ceramic fibers, polyamide fibers, graphite fibers, metal fibers and metal coated glass or graphite fibers, or mixtures thereof, wherein said fibers have an average length of from 3.2 mm to 25.4 mm and an aspect ratio of greater than 40.
Claim 4
Dependent Claim
22 words
The process of Claim 2, wherein said reinforcing fibers are glass fibers having an average length of from 3.2 to 19 mm.
Claim 5
Dependent Claim
65 words
The process of Claims 1, 2 or 3, wherein said binder is a water insoluble organic polymer particle having anionic or cationic bound charges and a - 00 particle size of from 500 A to 5000 A, and said binder being present in the amount of from 1 to 10 weight percent, based on the total weight, on a dry solids basis, of the composite.
Claim 6
Dependent Claim
29 words
- The process of any one of the preceding claims, wherein the thermoset resin is a vinyl terminated epoxy resin and the curing agent is a vinyl polymerizable monomer.
Claim 7
Dependent Claim
12 words
The process of Claim 5, wherein said vinyl polymerizable monomer is styrene.
Claim 8
Dependent Claim
35 words
The process of any one of Claims 1 to 4, wherein said thermoset resin is a phenol formaldehyde type resin and said latent curing agent is selected from hexamethylenetetraamine, urea formaldehyde, melamine formaldehyde and polyamines.
Claim 9
Dependent Claim
18 words
The process of any one of the preceding claims, wherein said curing agent is a free radical initiator.
Claim 10
Dependent Claim
18 words
The process of Claim 8, wherein said initiator is selected from peroxides capable of initiating free radical polymerization.
Claim 11
Dependent Claim
43 words
The process of any one of the preceding claims, wherein said composite includes from 1 to 10 percent by weight, based on the total dry weight of solids in the composite, of an additive selected from polymeric fibers, polyolefin paste and polyolefin pulp.
Claim 12
Dependent Claim
47 words
The process of any one of the preceding claims, wherein said composite includes up to 33 percent by weight, based on the total dry weight of solids in the composite, of a filler selected from silica compounds, CaCO 3 , MgO, Mg(OH) 2' CaSiO 3 and mica.
Claim 13
Dependent Claim
24 words
The process of any one of the preceding claims, wherein said flocculant is selected from partially hydrolyzed polyacrylamide, modified cationic polyacrylamide, and diallyldiethylammonium chloride.
Claim 14
Dependent Claim
19 words
The process of Claim 1 including the step of lofting said dried mat prior to said curing step (f).
References Cited (Backward Citations)
No citation records indexed.
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