EP0308286A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Reinforced thermoplastic sheet of high moldability
Assignee: ExxonMobil Chemical Patents Inc
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Filing: 1988-08-25
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Granted: —
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Expires: 2008-08-25
Abstract
Abstract This semifinished product is a non-densified flexible sheet containing, as an intimate mixture, reinforcing fibers dispersed in the unit state, particles of polyolefinic resin and at least one organic peroxide whose decomposition, during hot conversion of the sheet, gives the mixture a high moldability. The articles obtained by compression exhibit a homogeneous distribution of the reinforcing fibers.
Inventors
- 👤 Michel Goguelin
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 07:02
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/18; C08K; C08K5/00; C08K5/04; C08K5/14
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
56 words
A method of preparation of a flexible sheet comprising a thermoplastic resin and reinforcing fibers and intended for conversion by heating and molding, characterised in that it comprises incorporating in said sheet at least one organic peroxide, in the active state, whose decomposition temperature is compatible with the melting point and conversion temperature of the sheet.
Claim 2
Independent Claim
56 words
A method of preparation of a flexible sheet comprising a thermoplastic resin and reinforcing fibers and intended for conversion by heating and molding, characterised in that it comprises incorporating in said sheet at least one organic peroxide, in the active state, whose decomposition temperature is compatible with the melting point and conversion temperature of the sheet.
Claim 3
Dependent Claim
18 words
The method according to claim 1, wherein the resin is in the form of powder, fibers or fibrils.
Claim 4
Dependent Claim
15 words
The method according to claim 1 or claim 2, wherein the resin is a polyolefin.
Claim 5
Dependent Claim
13 words
The method according to claim 3, wherein the resin is a polypropylene homopolymer.
Claim 6
Independent Claim
33 words
The method according to any one of claims 1 to 4, wherein the peroxide is selected from monofunctional or polyfunctional peroxides whose temperature at which the half-life is 1 minute is above 170°.
Claim 7
Independent Claim
41 words
The method according to any one of claims 1 to 5, wherein the peroxide is selected from : - dicumyl peroxide - tert-butyl cumyl peroxide - 2,5-dimethyl-2,5-bis(tert-butylperoxy) hexane - 1,3-bis (tert-butyperoxyisopropyl) benzene - ditert-butyl peroxide - 2,5-dimethyl-2,5-bis (tert-butylperoxy) hexyne - 3,3,6,6,9,9-hexamethyl-1,2,4,5-textraoxacylononane
Claim 8
Independent Claim
35 words
The method according to any one of claims 1 to 6, wherein the peroxide is present in the sheet in a proportion of from 0.05 to 1% of the total dry weight of the sheet.
Claim 9
Independent Claim
36 words
The method according to any one of claims 1 to 7, wherein the reinforcing fibers are present in a proportion of 15 to 60%, preferably 20 to 40%, of the total dry weight of the sheet.
Claim 10
Independent Claim
33 words
The method according to any one of claims 1 to 8 wherein the reinforcing fibers are glass fibers preferably from 6 to 25mm long and/or preferably from 9 to 15 microns in diameter.
Claim 11
Independent Claim
22 words
The method according to any one of claims 1 to 9, which is a flexible sheet made by the wet paper-making process.
Claim 12
Dependent Claim
29 words
The method according to claim 10 wherein the peroxide under suspended form in an aqueous solution, is added to a slurry comprising polymer particles, reinforcing fibers and process aids.
Claim 13
Independent Claim
78 words
A method of forming a molding from a sheet obtained by the method according to any one of claims 1 to 10 which comprises heating the sheet to a temperature sufficient to melt the resin and decompose the peroxide, thereby degrading the resin and increasing its melt flow value, and coating and compressing the heated sheet in a mold of desired shape to form a molding of a continuous plastic matrix having discrete reinforcing fibers homogeneously dispersed therein.
References Cited (Backward Citations)
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