Patent US4427795A successfully refreshed from Google Patents.
US4427795A
Expired / Lapsed
US
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Rigid polyvinyl chloride foam
Assignee: Stamicarbon BV
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Filing: 1982-12-14
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Granted: 1984-01-24
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Expires: 2002-12-14
Abstract
Abstract New rigid polyvinyl chloride foam having a density of between 10 and 50 kg/m 3 and having a uniform, fine-celled cell-structure consisting of a rigid vinyl chloride homopolymer containing per 100 parts by weight of polyvinyl chloride 0.1-15 parts by weight of a homo- or copolymer of an alkyl methacrylate having an alkyl group of 1-10 carbon atoms and a method for the preparation of such a rigid polyvinyl chloride foam.
Inventors
- 👤 Antoon Dorrestijn
- 👤 Pieter J. Lemstra
- 👤 Lambert H. T. van Unen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 09:16
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/0061; C08J9/04; C08J9/12; C08J9/14; C08J9/143; C08J9/147; C08J2327/00; C08J2327/02; C08J2327/04; C08J2327/06; C08J2433/00; Y; Y10; Y10S; Y10S264/00; Y10S264/13
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
84 words
New rigid polyvinyl chloride foam having a density of between 10 and 50 kg/m 3 and having a uniform, fine-celled cell-structure with closed cells of which at least 95% have a cell diameter of at most 300 μm, consisting of a rigid vinyl chloride homopolymer containing per 100 parts by weight of polyvinyl chloride 0.1-15 parts by weight of a homo- or copolymer of an alkyl methacrylate having an alkyl group of 1-10 carbon atoms and foamed by use of a physical blowing agent.
Claim 2
Dependent Claim
84 words
New rigid polyvinyl chloride foam having a density of between 10 and 50 kg/m 3 and having a uniform, fine-celled cell-structure with closed cells of which at least 95% have a cell diameter of at most 300 μm, consisting of a rigid vinyl chloride homopolymer containing per 100 parts by weight of polyvinyl chloride 0.1-15 parts by weight of a homo- or copolymer of an alkyl methacrylate having an alkyl group of 1-10 carbon atoms and foamed by use of a physical blowing agent.
Claim 3
Dependent Claim
18 words
Rigid polyvinyl chloride foam according to claim 1, characterized in that said alkyl methacrylate is a methyl methacrylate.
Claim 4
Dependent Claim
101 words
Method for the preparation of a rigid polyvinyl chloride foam having a density of between 10 and 50 kg/m 3 and having a uniform, fine-celled cell-structure with closed cells of which at least 95% have a cell-diameter of at most 300 μm characterized in that a rigid vinyl chloride homopolymer provided with 0.1-15 parts by weight per 100 parts by weight of polyvinyl chloride of a homo- or copolymer of an alkyl methacrylate having an alkyl group of 1-10 carbon atoms is foamed with 5-50 parts by weight of a physical blowing agent per 100 parts by weight of polyvinyl chloride.
Claim 5
Dependent Claim
101 words
Method for the preparation of a rigid polyvinyl chloride foam having a density of between 10 and 50 kg/m 3 and having a uniform, fine-celled cell-structure with closed cells of which at least 95% have a cell-diameter of at most 300 μm characterized in that a rigid vinyl chloride homopolymer provided with 0.1-15 parts by weight per 100 parts by weight of polyvinyl chloride of a homo- or copolymer of an alkyl methacrylate having an alkyl group of 1-10 carbon atoms is foamed with 5-50 parts by weight of a physical blowing agent per 100 parts by weight of polyvinyl chloride.
Claim 6
Dependent Claim
16 words
Method according to claim 3, characterized in that methyl methacrylate is used as said alkyl methacrylate.
Claim 7
Dependent Claim
29 words
Process according to claim 3, characterized in that as physical blowing agent one or more fluoro chloro alkanes, by preference trichloro fluoro methane and/or dichloro difluoro methane, are used.
Claim 8
Dependent Claim
65 words
Method according to claim 3, characterized in that prior to the foaming a nucleating agent, preferably a very finely dispersed powder of one or more compounds, which under the circumstances during the foaming give off gaseous products, is added to the rigid polyvinyl chloride, by preference in an amount of 0.5-2 parts by weight of nucleating agent per 100 parts by weight of polyvinyl chloride.
Claim 9
Dependent Claim
41 words
Method according to claim 3, characterized in that the rigid vinyl chloride homopolymer with said homo- or copolymer of an alkyl methacrylate is first granulated via an extruder, subsequently this granulate is impregnated with the physical blowing agent and then foamed.
Claim 10
Dependent Claim
19 words
Method according to any claim 3, characterized in that the rigid vinyl chloride homopolymer is foamed via an extruder.
Claim 11
Dependent Claim
29 words
Method according to claim 7, characterized in that the impregnated granulate is placed in a mould and subsequently the granulate is foamed by heating the mould to 350-550 K.
Claim 12
Dependent Claim
38 words
Method according to claim 3, characterized in that all ingredients of the rigid polyvinyl chloride foam are introduced into the front part of an extruder and the physical blowing agent is introduced under pressure further down the extruder.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-01-23 | 1987-07-25 | 1988-01-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-01-23 | 1991-07-25 | 1992-01-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-01-23 | 1995-07-25 | 1996-01-24 | $7700.00 | Window Closed / Lapsed |