GB2116572A - High density flexible polyurethane foam - Google Patents
High density flexible polyurethane foam Download PDFInfo
- Publication number
- GB2116572A GB2116572A GB08206589A GB8206589A GB2116572A GB 2116572 A GB2116572 A GB 2116572A GB 08206589 A GB08206589 A GB 08206589A GB 8206589 A GB8206589 A GB 8206589A GB 2116572 A GB2116572 A GB 2116572A
- Authority
- GB
- United Kingdom
- Prior art keywords
- polyurethane foam
- foam
- high density
- flexible polyurethane
- powder
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 229920005830 Polyurethane Foam Polymers 0.000 title claims abstract description 33
- 239000011496 polyurethane foam Substances 0.000 title claims abstract description 31
- 238000000034 method Methods 0.000 claims abstract description 20
- 239000000203 mixture Substances 0.000 claims abstract description 13
- 238000002156 mixing Methods 0.000 claims abstract description 10
- 239000002699 waste material Substances 0.000 claims abstract description 10
- 239000004814 polyurethane Substances 0.000 claims abstract description 6
- 229920002635 polyurethane Polymers 0.000 claims abstract description 6
- 239000002245 particle Substances 0.000 claims abstract description 4
- 238000000465 moulding Methods 0.000 claims abstract description 3
- 239000000843 powder Substances 0.000 claims description 15
- 229920005862 polyol Polymers 0.000 claims description 7
- 150000003077 polyols Chemical class 0.000 claims description 7
- 239000004604 Blowing Agent Substances 0.000 claims description 6
- 239000003054 catalyst Substances 0.000 claims description 5
- 239000012948 isocyanate Substances 0.000 claims description 5
- 150000002513 isocyanates Chemical class 0.000 claims description 5
- 238000001035 drying Methods 0.000 claims description 4
- 238000004519 manufacturing process Methods 0.000 claims description 4
- 238000010298 pulverizing process Methods 0.000 claims description 2
- 238000012216 screening Methods 0.000 claims description 2
- 239000006260 foam Substances 0.000 abstract description 21
- 238000000227 grinding Methods 0.000 abstract 1
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 6
- 239000011541 reaction mixture Substances 0.000 description 5
- 238000006243 chemical reaction Methods 0.000 description 4
- 229920000642 polymer Polymers 0.000 description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 4
- 229910002092 carbon dioxide Inorganic materials 0.000 description 3
- 239000001569 carbon dioxide Substances 0.000 description 3
- 230000035699 permeability Effects 0.000 description 3
- 238000009826 distribution Methods 0.000 description 2
- 150000008282 halocarbons Chemical class 0.000 description 2
- 125000002887 hydroxy group Chemical group [H]O* 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 239000004721 Polyphenylene oxide Substances 0.000 description 1
- 229920013701 VORANOL™ Polymers 0.000 description 1
- 238000003915 air pollution Methods 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000007664 blowing Methods 0.000 description 1
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- IQPQWNKOIGAROB-UHFFFAOYSA-N isocyanate group Chemical group [N-]=C=O IQPQWNKOIGAROB-UHFFFAOYSA-N 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 229920000728 polyester Polymers 0.000 description 1
- 229920000570 polyether Polymers 0.000 description 1
- 229920001296 polysiloxane Polymers 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 239000004094 surface-active agent Substances 0.000 description 1
- 101150095744 tin-9.1 gene Proteins 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
- C08J9/0061—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof characterized by the use of several polymeric components
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
- B29B17/00—Recovery of plastics or other constituents of waste material containing plastics
- B29B17/0026—Recovery of plastics or other constituents of waste material containing plastics by agglomeration or compacting
- B29B17/0042—Recovery of plastics or other constituents of waste material containing plastics by agglomeration or compacting for shaping parts, e.g. multilayered parts with at least one layer containing regenerated plastic
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J3/00—Processes of treating or compounding macromolecular substances
- C08J3/12—Powdering or granulating
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J3/00—Processes of treating or compounding macromolecular substances
- C08J3/12—Powdering or granulating
- C08J3/122—Pulverisation by spraying
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2075/00—Use of PU, i.e. polyureas or polyurethanes or derivatives thereof, as moulding material
- B29K2075/02—Polyureas
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2375/00—Characterised by the use of polyureas or polyurethanes; Derivatives of such polymers
- C08J2375/04—Polyurethanes
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2475/00—Characterised by the use of polyureas or polyurethanes; Derivatives of such polymers
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/62—Plastics recycling; Rubber recycling
Landscapes
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Separation, Recovery Or Treatment Of Waste Materials Containing Plastics (AREA)
Abstract
A process of making higher density flexible polyurethane foam from waste polyurethane foam is accomplished by powdering the waste polyurethane foam and mixing it with any foamable polyurethane composition and moulding the mixture in a mould. Before mixing the powdered foam is sufficiently dried and screened to get a uniform particle size.
Description
SPECIFICATION
Method of producing high density flexible PU foam
This invention relates to a method of producing high density and resilience flexible polyurethane foam.
Polyurethane foam is generally formed by the reaction of isocyanate with a polymer having hydroxyl group or carboxyl group This polymer can be polyester or polyether, which is generally called polyol. During the reaction, the gas such as carbon dioxide generated causes the reaction mixture to swell into the form of foam. In case of polymer with hydroxyl group, to liberate carbon dioxide some free water must be contained in the reaction mixture. In some cases, halocarbon are added as a blowing agent. In these reactions, other chemicals such as catalyst surfactant are also used. It is importent that the reaction mixture must be rapidly and sufficiently mixed.
The polyurethane foam are divided into flexible foam semirigid foam and rigid foam. The flexible foam are easy to deform under load and can recover from deformation upon removal of load.
There are generally two processes for producing flexible polyurethane foam: one shot process and prepolymer process. The former process is done by mixing the properly formulated polyol, isocyanate, catalyst, blowing agent and then poured into the mold. In prepolymer process, polyol is firstly mixed with isocyanate to form a prepolymer which has terminal isocyanate group and is stable for storage. When the prepolymer reacts with blowing agent such as water in the presence of catalyst a polyurethane foam product can be obtained.
The polyurethane foams produced by the processes as described above are flexible foam and the density thereof is 1 8-30kg"m. These are low density flexible foams and have poor resilence and load characteristic so that they are mostly used as packing and rubbing materials. However, it is found that higher density polyurethane foam has better mechanical properties, resilence, comfort and air permeability and can be used in shoesole, hat liner and others where better load characteristic is required.
The higher density flexible foam can be produced under high molding pressure. This method is costly and the formed foam has a layer of skin surface that causes poor air permeability.
Although there are other high density forms made from other polymer, their comfort characteristic are not as satisfactory as polyurethane foam.
In accordance with the invention a higher density and resilence flexible polyurethane foam is made by firstly pulverizing a cured polyurethane foam and mixing the pulverized foam powder with a foamable polyurethane composition. The cured polyurethane foam may be either unused cured polyurethane foam or waste polyurethane foam or the mixture of both made by any process. As the waste polyurethane foam can be reused by this process, this is not only economical but also can save the energy supplied for treatment of waste foam.
It is preferable that the pulverized foam powder is sufficiently dried before mixing with foamable polyurethane composition so that these powder can be completely soaked in the viscous mixture.
The most preferable particle size of the powder is 0.5mm---3mm. To obtain a uniform size distribution of powder, the pulverized powder can be screened before mixing.
The foamable polyurethane composition may includes isocyanate, polyol or polyol blend, catalyst and blowing agent. Blowing agent can water or halocarbon or the mixture of both. The mixture are formulated with proper ratio and rapidly and thoroughly mixed with the pulverized foam powder of suitable weight, and then poured into the mold. The gas such as carbon dioxide liberated from the reaction acts as a blowing gas and cause foams in the mold. The cured foam is found, upon testing, that its density, resilence and load characteristic are higher than those produced by any known process as described above.
An object of the invention is to provide a method of making a higher density flexible polyurethane foam from waste polyurethane foam.
Another object of the invention is to provide a method of reusing waste polyurethane foam, thereby saving the production cost and the energy supply for treatment of waste polyurethane foam that can cause air pollution in the environment.
The following example is presented in illustration of the process of this invention and is not intended as an undue limitation on the generally broad scope thereof.
About 100 gm of waste polyurethane foam is ground into a powder form until the particle size thereof is 0.5m/m-a.0m/m. The powder is then placed in a drying apparatus for drying. After drying the powdered substance is subjected to screening to get a uniform size distribution. The screened powder is then put into a mixer into which 25gm of Voranol 3800 polyol, 12.5gm of
TDI, about 0.32gm of silicone and Tin-9 are further added.
After mixing for 30 minutes the reaction mixture is poured into the mold. At that time, the powder is completely soaked in the reaction mixture and uniformly incorporated with the formed foam which swells to a volume as large as five times. This expanded foam in the mold is then compressed mechanicaily and cooled at the room temperature for 24 hours. The cast foam is finally released from mold after cooling. This foam is a higher flexible polyurethane foam and test data for this foam are given as follows: 1. Density of PU foam 0.178g/cm3 2. Hardness (ASKER TYPE C) 37 3. Tensile strength 3.0kg/cm2 4. Elongation 65% 5. Influence of Heating No Stickiness and crack 6. Decrease in Elongation -8% 7. Decrease in tensile strength 7% 8. Air permeability 200 l/m2 sec.
9. Water vapour transmission
rate 3036 (g/m2/400C, Above
90% RH/24hrs)
Claims (8)
1. A method of making a high density and resilence flexible polyurethane foam comprising the steps of. pulverizing a cured polyurethane foam, mixing said pulverized polyurethane foam powder with a foamable polyurethane composition, and molding the mixture in a mold.
2. A method as claimed in Claim 1, wherein said cured polyurethane foam is waste polyurethane foam.
3. A method as claimed in Claim 2, wherein the foamable polyurethane composition consists essentially of, polyol, isocyanate, catalyst, blowing agent.
4. A method as claimed in Claim 3, further comprising the step of drying the pulverized powder before mixing.
5. A method as claimed in Claim 4, further comprising the step of screening the pulverized powder before mixing.
6. A method as claimed in Claim 5, wherein the particle size of pulverized powder is 0.5 mm- 3mm.
7. A method of making a high density resilient flexible polyurethane foam substantially as hereinbefore described.
8. A high density resilient flexible polyurethane foam manufactured substantially as hereinbefore described.
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8206589A GB2116572B (en) | 1982-03-05 | 1982-03-05 | High density flexible polyurethane foam |
| HK351/86A HK35186A (en) | 1982-03-05 | 1986-05-22 | Method of producing high density flexible pu foam |
| MY8600542A MY8600542A (en) | 1982-03-05 | 1986-12-30 | Method of producing high density flexible pu foam |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8206589A GB2116572B (en) | 1982-03-05 | 1982-03-05 | High density flexible polyurethane foam |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB2116572A true GB2116572A (en) | 1983-09-28 |
| GB2116572B GB2116572B (en) | 1985-10-30 |
Family
ID=10528822
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB8206589A Expired GB2116572B (en) | 1982-03-05 | 1982-03-05 | High density flexible polyurethane foam |
Country Status (3)
| Country | Link |
|---|---|
| GB (1) | GB2116572B (en) |
| HK (1) | HK35186A (en) |
| MY (1) | MY8600542A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1992002575A1 (en) * | 1990-08-08 | 1992-02-20 | Aps Welsch & Partner Gmbh | Reclaiming of foam off-cuts and/or waste foam |
| EP0555568A1 (en) * | 1992-02-14 | 1993-08-18 | Kun-Huang Chang | Process for making a foam material |
| WO1993019917A1 (en) * | 1992-03-30 | 1993-10-14 | Hecker Und Krosch Gmbh & Co. Kg | Method of recycling rigid expanded polyurethane |
| US5668189A (en) * | 1993-01-22 | 1997-09-16 | Woodbridge Foam Corporation | Foamed polymer and process for production thereof |
| WO2003008488A1 (en) * | 2001-07-16 | 2003-01-30 | Gefin S.R.L. | Recycling process for thermosetting elastomeric polyurethane waste |
| US7943676B2 (en) * | 2008-01-02 | 2011-05-17 | Kun-Huang Chang | Method of recycling waste plastic foam materials |
Citations (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB922306A (en) * | ||||
| GB805561A (en) * | 1955-03-17 | 1958-12-10 | Koepp & Co R Chem Fab Ag | Process for the production of foamed materials, using polyurethane foam waste |
| GB898272A (en) * | 1959-06-23 | 1962-06-06 | Dunlop Rubber Co | Polymeric foam articles |
| GB920272A (en) * | 1959-10-15 | 1963-03-06 | Aeropreen Ltd | Improvements in or relating to the bonding of particles of foamed material |
| GB1029961A (en) * | 1957-01-12 | 1966-05-18 | Dunlop Rubber Co | Improvements relating to cellular materials |
| GB1134751A (en) * | 1965-01-22 | 1968-11-27 | Gen Foam Products | Improvements relating to foamed materials |
| GB1138836A (en) * | 1965-02-12 | 1969-01-01 | Gen Foam Products | Improvements relating to foamed materials |
| GB1189996A (en) * | 1966-09-23 | 1970-04-29 | Gen Foam Products | Reconstituted Foam Material |
| GB1208544A (en) * | 1968-05-30 | 1970-10-14 | Semperit Ag | Improvements in or relating to laminated materials |
| GB1328171A (en) * | 1970-02-27 | 1973-08-30 | Schwarz I L | Method of and apparatus for the production of foam sheet material |
| GB1435210A (en) * | 1972-08-07 | 1976-05-12 | Balling Engelsen K | Method of manufacturing foamed polyurethane containing polyurethane scrap |
| GB1502777A (en) * | 1974-09-12 | 1978-03-01 | Ici Ltd | Polyurethane foams |
| GB2053944A (en) * | 1979-07-13 | 1981-02-11 | Hairlok Ltd | Utilisation of expanded polymer scrap |
| GB1595223A (en) * | 1977-02-02 | 1981-08-12 | Gen Foam Products | Flexible polyurethane sheet material |
-
1982
- 1982-03-05 GB GB8206589A patent/GB2116572B/en not_active Expired
-
1986
- 1986-05-22 HK HK351/86A patent/HK35186A/en not_active IP Right Cessation
- 1986-12-30 MY MY8600542A patent/MY8600542A/en unknown
Patent Citations (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB922306A (en) * | ||||
| GB805561A (en) * | 1955-03-17 | 1958-12-10 | Koepp & Co R Chem Fab Ag | Process for the production of foamed materials, using polyurethane foam waste |
| GB1029961A (en) * | 1957-01-12 | 1966-05-18 | Dunlop Rubber Co | Improvements relating to cellular materials |
| GB898272A (en) * | 1959-06-23 | 1962-06-06 | Dunlop Rubber Co | Polymeric foam articles |
| GB938868A (en) * | 1959-06-23 | 1963-10-09 | Dunlop Rubber Co | Material suitable for use in upholstery |
| GB920272A (en) * | 1959-10-15 | 1963-03-06 | Aeropreen Ltd | Improvements in or relating to the bonding of particles of foamed material |
| GB1134751A (en) * | 1965-01-22 | 1968-11-27 | Gen Foam Products | Improvements relating to foamed materials |
| GB1138836A (en) * | 1965-02-12 | 1969-01-01 | Gen Foam Products | Improvements relating to foamed materials |
| GB1189996A (en) * | 1966-09-23 | 1970-04-29 | Gen Foam Products | Reconstituted Foam Material |
| GB1208544A (en) * | 1968-05-30 | 1970-10-14 | Semperit Ag | Improvements in or relating to laminated materials |
| GB1328171A (en) * | 1970-02-27 | 1973-08-30 | Schwarz I L | Method of and apparatus for the production of foam sheet material |
| GB1435210A (en) * | 1972-08-07 | 1976-05-12 | Balling Engelsen K | Method of manufacturing foamed polyurethane containing polyurethane scrap |
| GB1502777A (en) * | 1974-09-12 | 1978-03-01 | Ici Ltd | Polyurethane foams |
| GB1595223A (en) * | 1977-02-02 | 1981-08-12 | Gen Foam Products | Flexible polyurethane sheet material |
| GB2053944A (en) * | 1979-07-13 | 1981-02-11 | Hairlok Ltd | Utilisation of expanded polymer scrap |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1992002575A1 (en) * | 1990-08-08 | 1992-02-20 | Aps Welsch & Partner Gmbh | Reclaiming of foam off-cuts and/or waste foam |
| EP0555568A1 (en) * | 1992-02-14 | 1993-08-18 | Kun-Huang Chang | Process for making a foam material |
| WO1993019917A1 (en) * | 1992-03-30 | 1993-10-14 | Hecker Und Krosch Gmbh & Co. Kg | Method of recycling rigid expanded polyurethane |
| US5525278A (en) * | 1992-03-30 | 1996-06-11 | Hecker Und Krosch Gmbh & Co. Kg | Recycling process and apparatus for rigid polyurethane foam |
| US5668189A (en) * | 1993-01-22 | 1997-09-16 | Woodbridge Foam Corporation | Foamed polymer and process for production thereof |
| WO2003008488A1 (en) * | 2001-07-16 | 2003-01-30 | Gefin S.R.L. | Recycling process for thermosetting elastomeric polyurethane waste |
| US7943676B2 (en) * | 2008-01-02 | 2011-05-17 | Kun-Huang Chang | Method of recycling waste plastic foam materials |
| TWI403547B (en) * | 2008-01-02 | 2013-08-01 |
Also Published As
| Publication number | Publication date |
|---|---|
| HK35186A (en) | 1986-05-30 |
| GB2116572B (en) | 1985-10-30 |
| MY8600542A (en) | 1986-12-31 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PE20 | Patent expired after termination of 20 years |
Effective date: 20020304 |