Patent US1357186A successfully refreshed from Google Patents.
EP0334829A1
Expired / Lapsed
EP
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Process for the treatment of polypropylene
Assignee: Total Petrochemicals Research Feluy SA
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Filing: 1989-02-20
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Granted: —
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Expires: 2009-02-20
Abstract
Abstract Isotactic polypropylene and/or ethylene-propylene copolymers are blended with 5-65 wt % of atactic polypropylene and with a thermosensitive agent. The process is particularly adapted for the incorporation of up to 20 wt % (based on the polymers) of prodegradants used for reducing the molecular weight and its distribution.
Inventors
- 👤 Claude Palate
- 👤 Alain Michel François Prevot
- 👤 René Venneman
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 16:47
CPC Classifications
C; C08; C08K; C08K5/00; C08K5/04; C08K5/14; B; B29; B29C; B29C48/00; B29C48/25; B29C48/92; C08F; C08F8/00; C08F8/50; C08L; C08L23/00; C08L23/02; C08L23/10; B29C2948/00; B29C2948/92; B29C2948/92504; B29C2948/92704; B29C48/022; B29C48/36; B29C48/395; C08F2810/00; C08F2810/10; C08L2205/00; C08L2205/02; C08L2207/00; C08L2207/10; C08L2207/14; C08L2312/00
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
113 words
1) Process for producing isotactic polypropylene and/or ethylene-propylene copolymer, hereinafter referred to as polypropylene, having improved spinning properties by incorporating a thermosensitive agent therein, characterized in that it comprises the steps consisting of : (i) preparing by extrusion an initial homogeneous blend comprising said polypropylene together with from 5% to 65% of atactic polypropylene; (ii) introducing in the feed hopper of an extruder the blend as prepared in step (i) simultaneously with the thermosensitive agent ; (iii) extruding the blend and introducing it into the extrusion die and then into a granulator to form polypropylene pellets comprising the thermosensitive agent; (iv) recovering the polypropylene pellets thus obtained, comprising the substantially intact thermosensitive agent.
Claim 2
Dependent Claim
113 words
1) Process for producing isotactic polypropylene and/or ethylene-propylene copolymer, hereinafter referred to as polypropylene, having improved spinning properties by incorporating a thermosensitive agent therein, characterized in that it comprises the steps consisting of : (i) preparing by extrusion an initial homogeneous blend comprising said polypropylene together with from 5% to 65% of atactic polypropylene; (ii) introducing in the feed hopper of an extruder the blend as prepared in step (i) simultaneously with the thermosensitive agent ; (iii) extruding the blend and introducing it into the extrusion die and then into a granulator to form polypropylene pellets comprising the thermosensitive agent; (iv) recovering the polypropylene pellets thus obtained, comprising the substantially intact thermosensitive agent.
Claim 3
Dependent Claim
19 words
2) Process according to Claim 1, wherein the initial homogeneous blend comprises from 5 to 50% of atactic polypropylene.
Claim 4
Dependent Claim
36 words
3) Process according to either of Claims 1 or 2, wherein the thermosensitive agent is a prodegradant agent introduced in an amount of from 0.01 to 20% by weight based on the total weight of polymer.
Claim 5
Dependent Claim
39 words
4) Process according to Claim 3 which consists of introducing simultaneously the homogeneous blend of polypropylene and atactic polypropylene with an amount of prodegradant agent comprised between 10 to 20% by weight based on the total weight of polymers.
Claim 6
Dependent Claim
25 words
5) Process according to Claim 3 which consists of using a prodegradant agent having a half-life time comprised between 1 and 5 minutes at 170°C.
Claim 7
Dependent Claim
39 words
6) Process according to Claim 3 which consists of carrying out the extrusion of the polymers and the prodegradant agent at a temperature comprised between 130 and 165°C during a residence time in the extruder of about 90 seconds.
Claim 8
Dependent Claim
20 words
7) Process according to Claim 3, wherein the prodegradant agent is selected from the group comprising 2,5-dimethyl-2,5-bis-(tert-butylperoxy)-hexyne-3 and 3,6,6,9,9-pentamethyl-3-(ethyl acetate)-1,2,4,5-tetraoxycyclononane.
Claim 9
Dependent Claim
35 words
8) Polypropylene pellets obtained in accordance with the process described in any one of the preceding claims and containing an amount of thermosensitive agent greater than 10% by weight based on the weight of polymers.
Claim 10
Dependent Claim
38 words
9) Use of the polypropylene pellets according to Claim 8 wherein said pellets are extruded under conditions causing the prodegradant remaining in said pellets to substantially completely react, to produce a polypropylene suitable for film or fibre forming.
Claim 11
Dependent Claim
36 words
10) Process according to either of Claims 1 or 2, wherein the thermosensitive agent is a blowing agent introduced in an amount of from 0.01 to 20% by weight based on the total weight of polymer.
Claim 12
Dependent Claim
35 words
11) Process according to either of Claims 1 or 2, wherein the thermosensitive agent is a fire-retardant agent introduced in an amount of up to 80% by weight based on the total weight of polymer.
Claim 13
Dependent Claim
30 words
12) Use of the polypropylene pellets obtained by the process of either of Claims 10 or 11, wherein said pellets are used as master batch in the extrusion of polypropylene.
References Cited (Backward Citations)
DE2311882A1
Cited
GB2100268A
Cited
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