WO1995033788A1 - Non-cfc foam produced using blended surfactants - Google Patents
Non-cfc foam produced using blended surfactants Download PDFInfo
- Publication number
- WO1995033788A1 WO1995033788A1 PCT/US1995/004219 US9504219W WO9533788A1 WO 1995033788 A1 WO1995033788 A1 WO 1995033788A1 US 9504219 W US9504219 W US 9504219W WO 9533788 A1 WO9533788 A1 WO 9533788A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- process according
- foam
- blowing agent
- resol
- weight
- Prior art date
Links
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
-
- 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
- C08J9/04—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent
- C08J9/12—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent by a physical blowing agent
- C08J9/14—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent by a physical blowing agent organic
- C08J9/149—Mixtures of blowing agents covered by more than one of the groups C08J9/141 - C08J9/143
-
- 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
- C08J2361/00—Characterised by the use of condensation polymers of aldehydes or ketones; Derivatives of such polymers
- C08J2361/04—Condensation polymers of aldehydes or ketones with phenols only
- C08J2361/06—Condensation polymers of aldehydes or ketones with phenols only of aldehydes with phenols
-
- 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
- C08J2471/00—Characterised by the use of polyethers obtained by reactions forming an ether link in the main chain; Derivatives of such polymers
Definitions
- TECHNICAL FIELD This invention relates to the manufacture of phenolic resol foams from phenol formaldehyde resins and more specifically to the manufacture of closed cell resol foams using surfactant blends.
- R is an alkyl group having 1 to 20 carbon atoms and x is an integer ranging from 4 to 120.
- the copolymer has a molecular weight ranging from 10,000 to
- the alkyl phenol is ethoxylated dodecylphenol wherein x ranges from 30 to 50.
- the blended surfactant preferably has ratio by weight of copolymer to alkyl phenol ranging from 75:25 to 25:75. More preferably the blended surfactant is equal parts by weight copolymer and alkylphenol.
- the blowing agent can be selected from a number of HCFCs or hydrofluorocarbons (HFCs).
- HFCs hydrofluorocarbons
- the HCFCs or HFCs have a boiling point below 0°C.
- Specific examples of these low boiling point blowing agents include l-chloro-l,l-difluoroethane (142b), dichlorofluoro-methane (22),
- the blowing agent also may include a perfluoroalkane wherein the perfluoroalkane comprises 1 to 5 weight percent of the total blowing agent weight.
- the perfluoroalkane is represented by the formula:
- n is an integer ranging from 4 to 20
- x is zero or an integer ranging from 2 to 10
- x + y 2n + 2.
- perfluoroalkane include dodecafluoropentane, tetradecafluorohexane, hexadecafluoroheptane.
- the perfluoroalkane comprises 1 to 3 weight percent and more preferably, 1 to 2 weight percent of total blowing agent weight.
- the cured resol foam has a density ranging from 0.5 to 3.0 pounds per cubic foot (8.009 to 48.055 kg/m 3 ).
- the resol foam density ranges from 0.7 to 1.8 pounds per cubic foot (11.213 to 28.833 kg/m 3 ).
- the resol resin preferably has a viscosity ranging from 5,000 cps to 40,000 cps (5 to 40 Pa.s) at 40°C.
- the resol resin has a viscosity ranging from 8,000 cps to 20,000 cps (8 to 20 Pa.s) at 40°C.
- the foams are prepared from resols which have been made using conventional starting mole ratios of phenol to formaldehyde, in the present case in the range of 1 : 1 to 1 :4.5, preferably 1 : 1.5 to 1 :2.5.
- the high mole ratio materials are the basis for resins which are substantially free of phenol and which can be treated with a formaldehyde co-reactant or scavenger, to reduce the initially high free formaldehyde content.
- the resin is concentrated to reduce the free water content of the resin.
- a typical viscosity resin used for manufacturing resol foam has a viscosity in the order of 5,000 to 40,000 cps (5 to 40 Pa.s) and a free water content of 4 to 8%.
- the resin utilized will preferably have a viscosity in the order of 8,000 to 20,000 cps (8 to 20 Pa.s) at 40°C.
- ramping postcure procedure according to the following: 0 to 70 minutes at 75-85°C followed by 20 to 105 minutes at 90-95°C followed by 60 to 170 minutes at 100-105°C.
- the purpose of the ramped postcure cycle is to reduce the cell wall damage that might otherwise occur to the foam if it was postcured under higher initial temperatures, while reducing the postcure time by gradually increasing the curing temperature, and therefore rate of cure, instead of maintaining the temperature at the relatively low initial.
- the low initial postcure temperature and the ramping cycle ensure that the green foam is not exposed to high temperatures when the foam cell walls are still weak and undercured.
- the ramping temperature cycle allows the foam cell walls to cure and strengthen at a more controlled rate, with a gradual elimination of the water vapour produced during the curing reaction.
- the result is a foam that can withstand the increased internal cell pressure and resist cell rupture at higher temperatures.
- a ramped postcure cycle reduces cell wall damage that would occur under more severe postcure conditions and improves the thermal performance of the foam.
- the choice of surfactant is critical in achieving a uniform closed cell structure which in turn is important in defining the thermal and mechanical properties of the foam. In addition to affecting the foam, the choice of surfactant can also impact the overall processing of the foam.
- This invention provides improved processing and producing of closed cell non-CFC resol foams using a blend of a high molecular weight ethylene oxide-propylene oxide block copolymer with an ethoxylated alkylphenol.
- Example 1- Preparation of Resol
- the resol resin used in the production of these foams used a formaldehyde:phenol (F P) mole ratio of 2.3:1, using 52% formaldehyde and 99% phenol.
- the reaction was carried out under basic conditions at elevated temperatures with 50% caustic solution. When the Ostwald viscosity of the resin reached 62 cst (0.000062 m 2 /s) (measured at 25°C), the reaction was cooled and neutralized with 50% aqueous aromatic sulphonic acid. Urea was added as a formaldehyde scavenger at a level of 77% by mole of the residual formaldehyde.
- the resin was passed through a thin film evaporator to reduce the water content from about 30% to 4-8%.
- An ethylene oxide based nonionic surfactant Pluronic F127 from BASF was then added in the molten state at 3.5% by weight of the resin and mixed into the resin to form a homogeneous mixture.
- the final viscosity of the resin was 9,000-12,000 cps (9 to 12 Pa.s) (measured at 40°C).
- Example 2 Preparation of a non-CFC Resol Foam
- the resol foam was prepared by mixing together the resol resin and surfactant with the blowing agent and acid catalyst using a high shear short residence, rotor/stator continuous mixer.
- the blowing agent was saturated with nitrogen at 200 psi (1.379 MPa) prior to introduction in the high shear mixer.
- the foaming catalyst was a blend of resorcinol, diethylene glycol, and a mixture of xylene and toluene sulphonic acids. (See U.S. Patent Nos. 4,883,824 and 4,945,077).
- the resol resin, blowing agent, and catalyst were continuously metered to the mixer by means of suitable flow metering devices in the following ratios: resin/surfactant 100
- the pressure inside the mixer be controlled to a range that prevents premature foaming, typically 170 to 250 psig (1.273 to 1.825 MPa). This pressure range depends on the vapor pressure and boiling point of the blowing agent and on the temperature in the mixer.
- a blowing agent such as HCFC141b, which has a boiling point of 32°C does not require the high operating pressures to prevent premature foaming because the vapor pressure is 35 psia (0.241 MPa) (at 60°C).
- very low boiling blowing agents like HCFC142b and particularly HCFC22 which boil at -9.8°C and -40.8°C respectively, require much higher mixer pressures to prevent premature foaming.
- the foamable mixture exited the mixer through evenly spaced tubes and nozzles to form continuous beads of froth on a moving facer. This resulted in parallel lines of foam which knitted together, as the froth expanded, to form a continuous sheet.
- the foam sheet then moved through a conveyor oven at approximately 80°C at a fixed rate to produce a board that was cured enough to handle.
- the boards underwent further curing using the following postcure cycle:
- Examples 3-4 The preparation of non-CFC resol foams in Examples 3 and 4 follow the procedure in Example 2 using resol resin from Example 1 with the exception of a change in surfactant.
- Formulations are shown in Table 1.
- the surfactant was a 40 mole ethoxylate of dodecylphenol, Harfoam PI.
- the surfactant was a 1/1 wt/wt blend of Harfoam PI and Pluronic F127. The surfactants were preblended in the specified ratio and then mixed, in a molten state, with the resol resin.
- Examples 5-8 The general resol resin preparation followed Example 2.
- the surfactant used and foam formulations are shown in Table 1.
- a blowing agent additive, perfluoroalkane (PFA) was used to reduce the foam cell size and improve thermal and mechanical properties of the foam.
- the specific PFA used in these examples was dodecafluoropentane (C j F 12 ) sold by 3M as PF-5050 Performance Fluid.
- C j F 12 dodecafluoropentane
- a preweighed quantity of PFA was blown, with nitrogen, into the bottom of an enclosed pressure vessel containing HCFC142b, to give a 98/2 wt/wt ratio of HCFC142b/PFA.
- This blowing agent/PFA blend was then saturated with nitrogen to 200 psi (1.379 MPa).
- Product properties for Examples 5-8 are shown in Table 2.
- premature frothing of the blowing agent can be controlled by mixer head pressure.
- the foam froth can be described as having a "dry” or fluffy appearance.
- an excessive amount of blowing agent is required to produce a foam board, to compensate for blowing agent losses during foaming. This method of compensation can be very costly.
- Another negative effect of a "dry" froth is a poor ability of the foam beads to knit together to form a continuous board.
- a "wet" laydown is caused by very high mixer pressure and can have a detrimental effect on the early stages of nucleation and cell formation. Although the knitting ability of the froth improves in a "wet” laydown, the processing of the uncured foam is more difficult, because "wet" foam has a greater tendency to adhere to hardware at various points throughout the process (for example, side guides), requiring costly production downtime for cleaning.
- F 127 is a gelling surfactant and it is believed that this surfactant gels in the presence of the water in the resin (up to 8%) and other water generated during the curing and crosslinking reactions. The gelation causes the viscosity of the foaming material to rise dramatically after mixing, reducing or preventing the drainage of polymer from the cell windows.
- Example 4 In an attempt to reduce the "wetness" of the froth, a 1/1 blend of F 127 and Harfoam PI was tried (Example 4) and resulted in a foam that was less prone to sticking to the foam oven, using less blowing agent. This foam was made with up to 10% less blowing agent than either F127 or Harfoam PI foams and had better thermal and mechanical properties.
- friability is measured according to the ASTM method C421 and is reported as weight loss as a percent of the whole. The objective is to produce a foam with a low friability.
- Table 2 shows that surfactant blend improved the friability (compare Examples 2 and 4) even at the slightly lower density of 2.5 pcf (40.046 kg/m 3 ) compared to 2.9 pcf (46.454 kg/m 3 ).
- Examples 5-7 demonstrate a similar surfactant effect but at a significantly lower foam density. A reduction in blowing agent of approximately 15% was observed for both the Harfoam PI and surfactant blend with good thermal properties and friability.
- Example 8 demonstrates the ability of this technology to produce a low density foam at 0.92 pcf (14.737 kg/m 3 ) with good initial thermal properties.
- a blend of surfactants can be used to improve the manufacturing of non-CFC resol foams. By blending two nonionic surfactants, a high molecular weight ethylene oxide-propylene oxide block copolymer and a lower molecular weight ethoxylated dodecylphenol, foam properties were maintained and an improvement in the production of the foam was observed. Because the surfactant blend modified the froth properties, less blowing agent was required, making the process more economical, and sticking of uncured or partially cured foam to hardware in the oven was substantially reduced or eliminated. TABLE 1: RESOL FOA ⁇ 4 FORMULATIONS
- blowing agent quantity measured as parts per hundred parts resin/surfactant, includes PFA.
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
- Compositions Of Macromolecular Compounds (AREA)
Abstract
Description
Claims
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1019950703335A KR0160242B1 (en) | 1994-06-09 | 1995-04-04 | Non-cfc foam produced using mixed surfactants |
DE69510939T DE69510939T2 (en) | 1994-06-09 | 1995-04-04 | FCK-FREE FOAM MADE WITH MIXED SURFACE-ACTIVE SUBSTANCES |
AU22409/95A AU2240995A (en) | 1994-06-09 | 1995-04-04 | Non-cfc foam produced using blended surfactants |
EP95915566A EP0764184B1 (en) | 1994-06-09 | 1995-04-04 | Non-cfc foam produced using blended surfactants |
CA002191598A CA2191598C (en) | 1994-06-09 | 1995-04-04 | Non-cfc foam produced using blended surfactants |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US08/257,407 US5407963A (en) | 1994-06-09 | 1994-06-09 | Non-CFC foam produced using blended surfactants |
US08/257,407 | 1994-06-09 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO1995033788A1 true WO1995033788A1 (en) | 1995-12-14 |
Family
ID=22976196
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US1995/004219 WO1995033788A1 (en) | 1994-06-09 | 1995-04-04 | Non-cfc foam produced using blended surfactants |
Country Status (9)
Country | Link |
---|---|
US (1) | US5407963A (en) |
EP (1) | EP0764184B1 (en) |
JP (1) | JP2750005B2 (en) |
KR (1) | KR0160242B1 (en) |
AU (1) | AU2240995A (en) |
CA (1) | CA2191598C (en) |
DE (1) | DE69510939T2 (en) |
TW (1) | TW354315B (en) |
WO (1) | WO1995033788A1 (en) |
Families Citing this family (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5973018A (en) * | 1995-10-04 | 1999-10-26 | Owens-Corning Fiberglas Technology, Inc. | Process for producing shaped phenolic foams |
KR100501989B1 (en) * | 1996-10-22 | 2005-07-18 | 오웬스 코닝 | The manufacture of non-cfc cellular resol foams using perfluorinated ethers |
CA2286751A1 (en) * | 1997-05-02 | 1998-11-12 | Jiffy Foam, Inc. | Method for making a closed-cell phenolic resin foam |
US5817706A (en) * | 1997-08-27 | 1998-10-06 | Owens Corning Fiberglas Technology, Inc. | Manufacture of non-CFC cellular resol foams using perflurinated ethers |
US6492432B1 (en) * | 1999-11-09 | 2002-12-10 | American Foam Technologies, Inc. | Novolac-epoxy resin foam, foamable composition for making novolac-epoxy resin foam and method of making novolac-epoxy resin foam |
WO2010053093A1 (en) | 2008-11-07 | 2010-05-14 | 旭化成建材株式会社 | Expandable phenolic resin composition, phenolic resin foam, and process for producing the phenolic resin foam |
KR102190552B1 (en) * | 2015-03-24 | 2020-12-14 | 아사히 가세이 겐자이 가부시키가이샤 | Phenol resin foam and method for producing same |
EP3176206A1 (en) * | 2015-12-01 | 2017-06-07 | Evonik Degussa GmbH | Method for the preparation of fine cell foams using a cell aging inhibitor |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2933461A (en) * | 1954-08-31 | 1960-04-19 | Westinghouse Electric Corp | Method for producing a cured expanded phenolic-aldehyde resin |
US4530939A (en) * | 1982-02-11 | 1985-07-23 | The Dow Chemical Company | Low K-factor closed cell phenol-aldehyde foam and process for preparation thereof |
EP0242620A2 (en) * | 1986-04-18 | 1987-10-28 | FIBERGLAS CANADA Inc. | Modified phenolic foam catalysts and method |
EP0305084A2 (en) * | 1987-08-28 | 1989-03-01 | FIBERGLAS CANADA Inc. | Process for manufacturing closed cell phenolic foams |
EP0439283A1 (en) * | 1990-01-20 | 1991-07-31 | BP Chemicals Limited | Process for producing phenolic resins using blowing agents |
Family Cites Families (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3389094A (en) * | 1963-10-10 | 1968-06-18 | Union Carbide Corp | Foaming phenol-formaldehyde resins with fluorocarbons |
US4412014A (en) * | 1980-01-21 | 1983-10-25 | The Celotex Corporation | Extraction of polyoxyalkylene surfactants for phenolic foam stabilization |
US4423163A (en) * | 1980-10-09 | 1983-12-27 | Koppers Company, Inc. | Method of producing phenolic foam using pressure and foam produced by the method |
US4900759A (en) * | 1981-05-20 | 1990-02-13 | Monsanto Company | Phenolic foams |
US4444912A (en) * | 1981-07-10 | 1984-04-24 | Koppers Company, Inc. | Phenolic foam and composition and method for preparing the same |
US4539338A (en) * | 1982-07-09 | 1985-09-03 | Koppers Company, Inc. | Phenol formaldehyde resoles for making phenolic foam |
US4546119A (en) * | 1984-11-29 | 1985-10-08 | Fiberglas Canada, Inc. | Closed cell phenolic foam |
JPS61283631A (en) * | 1985-06-10 | 1986-12-13 | Sumitomo Deyurezu Kk | Production of phenolic resin foam |
US4883824A (en) * | 1986-04-18 | 1989-11-28 | Fiberglas Canada, Inc. | Modified phenolic foam catalysts and method |
US4956394A (en) * | 1989-12-12 | 1990-09-11 | Thermal Products International | Closed cell phenolic foam containing alkyl glucosides |
BE1006021A3 (en) * | 1992-07-13 | 1994-04-19 | Recticel | METHOD FOR PRODUCING AN ESSENTIALLY closed cell phenolic foam. |
-
1994
- 1994-06-09 US US08/257,407 patent/US5407963A/en not_active Expired - Lifetime
-
1995
- 1995-04-04 WO PCT/US1995/004219 patent/WO1995033788A1/en active IP Right Grant
- 1995-04-04 JP JP8500832A patent/JP2750005B2/en not_active Expired - Lifetime
- 1995-04-04 DE DE69510939T patent/DE69510939T2/en not_active Expired - Lifetime
- 1995-04-04 KR KR1019950703335A patent/KR0160242B1/en not_active IP Right Cessation
- 1995-04-04 AU AU22409/95A patent/AU2240995A/en not_active Abandoned
- 1995-04-04 CA CA002191598A patent/CA2191598C/en not_active Expired - Fee Related
- 1995-04-04 EP EP95915566A patent/EP0764184B1/en not_active Expired - Lifetime
- 1995-04-07 TW TW084103315A patent/TW354315B/en not_active IP Right Cessation
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2933461A (en) * | 1954-08-31 | 1960-04-19 | Westinghouse Electric Corp | Method for producing a cured expanded phenolic-aldehyde resin |
US4530939A (en) * | 1982-02-11 | 1985-07-23 | The Dow Chemical Company | Low K-factor closed cell phenol-aldehyde foam and process for preparation thereof |
EP0242620A2 (en) * | 1986-04-18 | 1987-10-28 | FIBERGLAS CANADA Inc. | Modified phenolic foam catalysts and method |
EP0305084A2 (en) * | 1987-08-28 | 1989-03-01 | FIBERGLAS CANADA Inc. | Process for manufacturing closed cell phenolic foams |
EP0439283A1 (en) * | 1990-01-20 | 1991-07-31 | BP Chemicals Limited | Process for producing phenolic resins using blowing agents |
Also Published As
Publication number | Publication date |
---|---|
EP0764184B1 (en) | 1999-07-21 |
US5407963A (en) | 1995-04-18 |
EP0764184A1 (en) | 1997-03-26 |
JPH09503547A (en) | 1997-04-08 |
DE69510939T2 (en) | 2000-03-16 |
CA2191598C (en) | 2007-01-09 |
CA2191598A1 (en) | 1995-12-14 |
KR0160242B1 (en) | 1999-01-15 |
TW354315B (en) | 1999-03-11 |
JP2750005B2 (en) | 1998-05-13 |
DE69510939D1 (en) | 1999-08-26 |
AU2240995A (en) | 1996-01-04 |
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