Patent EP0300909A1 successfully refreshed from Google Patents.
EP0300909A1
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Reinforced thermoplastics sheet and its manufacturing process
Assignee: ExxonMobil Chemical Patents Inc
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Filing: 1988-07-21
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Granted: —
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Expires: 2008-07-21
Abstract
Abstract Fiber reinforced thermoplastics sheet is produced by a wet method from (a) an aqueous dispersion of reinforcing fibers and dispersing agent; and (b) an aqueous dispersion of thermoplastics polymer powder and an ionic polymer additive of opposite charge to the fiber dispersion. The dispersions are mixed, a high molecular weight ionic polymer flocculating agent is added, of charge opposite to that of the mixture, and the resulting suspension is drained and dried to form the sheet.
Inventors
- 👤 Michel Goguelin
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 07:26
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/18; D; D21; D21H; D21H17/00; D21H17/20; D21H17/33; D21H17/34; D21H17/41; D21H17/42; D21H17/43; D21H17/35; D21H17/37; D21H17/375; D21H23/00; D21H23/76; D21H23/765; D21H13/00; D21H13/10; D21H13/12; D21H13/14; D21H13/36; D21H13/38; D21H13/40; D21H17/44; D21H17/45; D21H21/00; D21H21/06; D21H21/08; D21H21/14; D21H21/28
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
109 words
Process for preparing by the wet method a reinforced thermoplastics semi-finished product in sheet form, which process comprises the following steps: a) providing a first aqueous dispersion of a dispersing agent with reinforcing fibers, b) providing a second aqueous dispersion containing at least one thermoplastics polymer powder and at least one ionic polymer additive of opposite charge to that of the first dispersion, c) mixing the two dispersions to form a mixture, d) incorporating into the mixture a flocculating agent in ionic polymer form, of high molecular weight and of charge opposite to that of said mixture, and e) draining the resulting suspension and drying the resulting semi-finished product.
Claim 2
Dependent Claim
109 words
Process for preparing by the wet method a reinforced thermoplastics semi-finished product in sheet form, which process comprises the following steps: a) providing a first aqueous dispersion of a dispersing agent with reinforcing fibers, b) providing a second aqueous dispersion containing at least one thermoplastics polymer powder and at least one ionic polymer additive of opposite charge to that of the first dispersion, c) mixing the two dispersions to form a mixture, d) incorporating into the mixture a flocculating agent in ionic polymer form, of high molecular weight and of charge opposite to that of said mixture, and e) draining the resulting suspension and drying the resulting semi-finished product.
Claim 3
Dependent Claim
33 words
Process according to claim 1, wherein the thermoplastics components and the reinforcements constituted of the fibers and optional fillers represent from 98 to 99.5% of the total dry weight of the semi-finished product.
Claim 4
Dependent Claim
14 words
Process according to claim 1 or 2, wherein the powder is a polyolefin resin.
Claim 5
Dependent Claim
30 words
Process according to claim 1, 2 or 3 wherein the reinforcing fibers comprise cylindrical fibers, the powder/cylindrical fibers ratio being between 1.5 and 5.7, and preferably between 2 and 3.
Claim 6
Dependent Claim
15 words
Process according to any one of the preceding claims wherein the reinforcing fibers comprise glassfibers.
Claim 7
Dependent Claim
30 words
Process according to any one of the preceding claims wherein the reinforcing fibers comprise from 15 to 60% and preferably 20 to 40% by dry weight of the semi-finished product.
Claim 8
Dependent Claim
29 words
Process according to any one of the preceding claims wherein the length of the reinforcing fibers is from 5 to 30 mm, and preferably from 6 to 25 mm.
Claim 9
Dependent Claim
23 words
Process according to any one of the preceding claims wherein the reinforcing fibers have a unit diameter in the range of 10-20 microns.
Claim 10
Dependent Claim
21 words
Process according to any one of the preceding claims wherein the mean granulometry of the powder is less than 800 microns.
Claim 11
Dependent Claim
26 words
Process according to any one of the preceding claims wherein the first dispersion includes a cationic dispersing agent preferably one comprising one or more fatty acids.
Claim 12
Dependent Claim
32 words
Process according to any one of the preceding claims wherein the dispersing agent is used in the proportion of from 5 to 15% with respect to the weight of the reinforcing fibers.
Claim 13
Dependent Claim
20 words
Process according to any one of the preceding claims wherein the first dispersion further includes cellulosic fibers and/or polyolefin pulp.
Claim 14
Dependent Claim
29 words
Process according to any one of the preceding claims wherein the second dispersion further includes one or more additives selected from dyes, thermal stabilizers, antistatic agents and age-protecting agents.
Claim 15
Dependent Claim
34 words
Process according to any one of the preceding claims wherein the second dispersion comprises from 0.1 to 0.5% of the ionic polymer additive with respect to the dry weight of powdered material contained therein.
Claim 16
Dependent Claim
34 words
Process according to any one of the preceding claims wherein the ionic polymer additive component of said second dispersion comprises an anionic polycarboxylic polymer, preferably an ethylene/acrylic acid copolymer or a partially hydrolysed polyacrylamide.
Claim 17
Dependent Claim
39 words
Process according to any one of the preceding claims wherein the ionic polymer flocculating agent is incorporated into the mixture in the proportion of from 0.5 to 1.5% with respect to the dry weight content of the aqueous suspension.
Claim 18
Dependent Claim
19 words
Process according to any one of the preceding claims wherein the ionic polymer flocculating agent comprises a cationic polyacrylamide.
Claim 19
Dependent Claim
69 words
Process according to any one of the preceding claims wherein simultaneously with or subsequent to the drying stage, at least the surface region of the semi-finished product is brought to a temperature at least equal to the softening temperature of the (or the lowest melting of the) thermoplastic polymer(s) so as to at least partially melt and coalesce said polymer thereby bonding the reinforcing fibres within the semifinished product.
Claim 20
Dependent Claim
63 words
A semi-finished reinforced thermoplastics product in sheet form, comprising from 96 to 99.5%, preferably from 98 to 99.5% by weight of well dispersed and uniformly distributed thermoplastics component, reinforcing fibers and optionally reinforcing filler(s), the balance including the residues of dispersing agents, ionic polymer additives and flocculating agents derived from the process by which said product is formed, but preferably excluding latex binders.
Claim 21
Dependent Claim
63 words
A semi-finished reinforced thermoplastics product in sheet form, comprising from 96 to 99.5%, preferably from 98 to 99.5% by weight of well dispersed and uniformly distributed thermoplastics component, reinforcing fibers and optionally reinforcing filler(s), the balance including the residues of dispersing agents, ionic polymer additives and flocculating agents derived from the process by which said product is formed, but preferably excluding latex binders.
Claim 22
Dependent Claim
50 words
A moulded article comprising a semi-finished product according to claim 19 or produced by the process according to any one of claims 1 to 18, which has been subjected to a shaping operation under applied pressure and at a temperature sufficient to melt the thermoplastics component of said semi-finished product.
References Cited (Backward Citations)
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