Literature

Proceedings of the Polyurethane Foam Association Technical Program May and October, 1996

New Insights Into Flame Lamination: Greg Howard, Albright & Wilson Americas, Proceedings of the Polyurethane Foam Association, October 17 & 18, 1996.

Flame bonding has been at best an inexact science. The reason that some foams bond well while others do not has been most perplexing. Sometimes foams from the same production lot or within the same roll perform differently. This report establishes a means of more accurately predicting performance as well as providing a tool to help evaluate problems that do arise.

Using standard 1.5 PCF automotive foams, the effects of gas type, flame height, flame spread, foam burn off, fabric, and nip pressure, on bond strength were measured. Pieces or the original laboratory foams were also prepared for acid evaluation.

The results of these evaluations demonstrate a direct relationship between acid and bond strengths in laminated foam fabric pieces. Without exception the higher the acid level the stronger the bond.

It is expected that this information can be used to develop new products for improved flame lamination, serve as analytical tools to help resolve quality issues, and provide some understanding and insight into the flame lamination process.

Proposed Federal Regulation for the Flexible Polyurethane Industry: Susan Wyatt, U. S. Environmental Protection Agency, Proceedings of the Polyurethane Foam Association, October 17 & 18, 1996.

This presentation was made to the Polyurethane Foam Association to notify the industry of upcoming EPA regulatory activity. It was designed to answer questions about the regulation and process, to explain the proposed regulatory requirements, and to inform the industry of opportunities to participate.

The legislation limits or prohibits emission of 118 Hazardous Air Pollutants including methylene chloride, toluene diisocyanate (TDI), methylene diphenyl diisocyanate (MDI) and methyl chloroform (1,1,1,-trichloroethane). The regulation applies to molded, slabstock, and rebond foam producers. It is applicable nationwide, and applies only to major sources of hazardous air pollutants.

The paper discusses the segments of the polyurethane industry, which are covered by the proposed legislation and those who are exempt. The compliance date, molded foam requirements, rebond foam requirements, slabstock foam requirements, slabstock foam requirements for TDI and HAP ABA and equipment cleaning requirements are presented. A question and answer section on specific issues is also given.

Foam Hysteresis and Formulation Variables: James E. Knight, ARCO Chemical Company, Proceedings of the Polyurethane Foam Association, October 17 & 18, 1996.

Auxiliary blowing agents are essential at this time for the production of flexible slabstock foams. Today the flexible slabstock industry is faced with the possible loss of the ability to use auxiliary blowing agent because of legislative actions arising from environmental concerns of worker health concerns. This issue has prompted considerable work by foam manufacturers, chemical suppliers and machinery manufacturers to develop technologies for the production of foams without or with reduced levels of auxiliary blowing agents such as methylene chloride. To this end there are two objectives: first, to make foams with densities comparable to foams made with auxiliary blowing agents; and secondly, to make foams in the full range of softness/hardness for today’s range of foam applications.

The effects of formulation variables such as water, methylene chloride, TDI index, airflow, flame retardants, polymer polyol, and morphology modifiers (softening agents) on hysteresis were evaluated. The hysteresis of conventional foam vs. HR foam was also looked at.

It was found that formulation water content has a profound influence on the hysteresis of particular slabstock foam while methylene chloride has none. The airflow, addition of flame retardant and morphology modifiers have slight positive effects and increase hysteresis. Increasing TDI index, the addition of polymer polyols, and the addition of inorganic fillers have slight negative effects and decrease the gysteresis of a foam.

The Effect of Fogging of Common FR Additives in Flexible Foam: L. Bradford and E. Pinzoni (US) and J. Wuestenenk (Holland), Akzo Nobel Central Research, Proceedings of the Polyurethane Foam Association, October 17 & 18, 1996.

As a result of design changes in automobile wind screens, temperatures above 100 degrees centigrade have been measured in the interior of cars. Such high temperatures lead to evaporation of volatile materials used in the interior of cars. Condensation (fogging) deposits on the windows of cars.

The automotive manufacturers are asking for FR’s with good fogging properties with reference to reflectance (>60%) and gravimetric results (<1mg*.) specification may vary. This paper attempts to clarify some of the confusion in the industry regarding test data, and the contribution of flame retardants (FR’s).

Data is presented which shows the relative fogging performance of some of the most common FR additives and two experimental additives. Testing is on foam samples not raw materials. Foams were prepared containing no flame retardant, 5 parts of FR and 15 parts of FR, at a density of 1.8 lbs./cu ft. One additional set of data compares 1.2 and 1.8 density foams to show impact of foam density on fogging.

The Fogging test conditions shown, with resulting product classification, include those required by Ford General Motors, Mercedes, and Toyota.

The conclusions from these evaluations are as follows:

A. Non reactive oligomers can be good FR’s for fogging behavior in the automotive foams, either in gravimetric or photometric methods.
B. Reactive oligomers should also give good fogging behavior in both methods.
C. TDCP (Fyrol FR-2) also gives good results in the photometric method, and slightly better results in the gravemetric methods.
D. Oligomer 2 (Fyrol 99) had slightly worse performance than TDCP (Fyrol FR-2).
E. TCPP (Fyrol PCF) gave the worst results in either gravimetric or photometric methods.
F. TCPP should not be used if fogging is a major concern in the final application. The reproducibility of the gravimetric method is good.
G. The reproducibility of the photometric method is poor
H. Density has a direct impact on fogging.

The Flexible Foam Market in Australia David Gilliver, Dunlop Foam & Fibre Group, South Dandenong, Victoria Australia, Proceedings of the Polyurethane Foam Association, October 17 & 18, 1996.

Australia is one of the largest continents on Earth by land area, but has a relatively small population of 18 million people. The nations per capita consumption of polyurethane foam is among the world’s highest, being only slightly lower than the USA.

This paper discusses the demographics of the Australian Market. Foaming Technologies, Raw Materials, Polyester Foams, Visco-Elastic (Low Resilience) Foams, Quality Changes, Molded Flexible Foams, Other End Uses, Regulatory Issues and Recycling.

A New Flame Retardant Additive for Flexible Polyurethane Foam: R. S. Rose, L. J. Likens, J. L. Elliott, Great Lakes Chemical Corporation, West Lafeyette, Indiana, Proceedings of the Polyurethane Foam Association, May 17 & 18, 1996.

This paper introduces a new bromine based flame retardant that provides the same efficiency as well as the hydrolytic and thermal stability as the diphenyl oxide based flame retardants without the regulatory threats associated with the latter.

The new flame retardant has been designated CN-2065. It is a low viscosity bromine containing liquid which can be used alone or with phosphorus compounds CN-2065 is evaluated in both 1.5 PCF automotive polyester polyurethane foam and in typical polyether polyurethane furniture foam formulations meeting California Bulletin 117 flammability requirements.

The polyester foam evaluation indicated that the new flame retardant, CN-2065, provides the stability of aromatic bromine without a diphenyl oxide base. It is an alternative for polyester polyurethane foams requiring long term hydrolysis resistance in humid environments.

This new flame retardant also performs in polyether polyurethane foam. In addition to being scorch resistant, there is an indication that its plasticizing characteristics are suited to flame lamination applications.

New Developments in Non-Halogenated Flame Retarded Flexible PUF: M. Sicken, Hoechst AG, Hurth, Germany, C. Schultz, Hoechst AG, Frankfort, Germany, Proceedings of the Polyurethane Foam Association, October 17 & 18, 1996.

Hoechst has taken the challenge to develop flame retardants which not only meet the basic requirements concerning flame retardant efficiency and polymer compatibility, but also with regard to cost effectiveness and to environmental questions such as emission properties and recyclability. Hoechst is of the opinion that flame retardants that contain only phosphorus have substantial advantages compared to the widely used halogenated phosphate esters and the brominated and / or chlorinated polyols.

The comparative burning behavior of flexible foams prepared with Hoecst’s Hostaflam TP OP 550, a reactive all phosphorus based flame retardant containing 17.5% phosphorus, compared to TCPP, TDCPP and a chlorinated diphospate ester is evaluated.

The authors conclude that Hostaflam TP OP 550 meets industry requirements for flame retardant efficiency and cost effectiveness, and also earns high marks on environmental aspects demonstrated by low emission data in terms of fogging values and smoke gas properties.

Advances in Blowing Agent Reduction with Geolite Modifier Technology: Ray Ricciardi, OSI Specialties, Proceedings of the Polyurethane Foam Association, October 17 & 18, 1996.

OSI Specialties Geolite modifier additives have grown in sales as government regulations force more and more slab foamers to reduce auxiliary blowing agents from their formulations. Earlier products, Geolite modifier 91 and Geolite modifier 205, demonstrated much progress towards this objective by reducing blowing agent concentration approximately 30% and 60% respectively in an OSI grouping of typical slab formulations. The new Geolite modifier 210 product and technology reportedly reduces blowing agents by over 90% in the OSI grouping of typical slab formulations.

Geolite modifier 210 can be used in most foam grades. It offers varying levels of ABA reduction depending on the foam grade and whether mechanical cooling is used. A 100% reduction in ABA can be achieved in most foam grades without mechanical cooling. The exceptions are where foam exotherms become unsafe when excess water is used as a blowing agent. Some ABA may be required for high or low density super-soft foams. Mechanical cooling can complement this technology by cooling the low density hard foam grades.

Since more rapid foam cure can be achieved with GM-210, foams can be cooled to achieve acceptable foam physical properties before the foam blocks reach unsafe temperatures. Cooling can also minimize foam degradation or discoloration, which can occur from high foam exotherms.

OSI believes that GM-210 technology is a significant technical development that will help the slab foam industry to economically reduce chemical blowing agents.

Controlled Environmental Foaming: Scott Carson, Foam One, Dario Ramazzotti, Edge Sweets Co., Proceedings of the Polyurethane Foam Association, October 17 & 18 1996.

In May 1994, Foam One introduced for licensing the patented Controlled Environment Foaming (CEF) manufacturing process to the PFA. Foam One technology meets environmental goals by eliminating the need for auxiliary blowing agents, all cleaning solvents, and by the use of carbon scrubbers to capture all TDI emissions present during the foaming stage of production. Additional features of this technology permit the foam producers to manufacture many unique foams. As a result, foam manufacturers are now able to penetrate markets, which previously were not available to the foam industry.

The purpose of this paper is to update the industry on the current status of the Foam.

One process and outline feature of many of the unique foams currently being produced use this technology. All existing foam products including filled foams can be manufactured by the Foam One process. When using vacuum, a low density, ultra soft grade of foam can be manufactured. When convoluted, this product can be used in place of polyester wrap for furniture cushions or in any other place where polyester batting is currently being used.

The use of pressure during foaming allows the production of very high compressive strength foam. This particular foam is successfully replacing polyethylene foam in packaging applications.

Several other Foam One process capabilities are also discussed which provide the urethane foam producer with a method of manufacturing new and profitable products for their company. Foam One technicians provide the necessary procedures and training for the start up of Foam One machinery.

Versatile HR Slabstock Foam Technology: T. M. Smiecinski, D. C. Mente, S. E. Wujcik, BASF Corporation, Proceedings of the Polyurethane Foam Association, October 17 & 18, 1996.

Traditionally manufacturers of HR foam focused on up-scale furniture and bedding applications. During the early 1980’s some foamers tried to develop and market highly flame retardant foams for high risk applications such as auditoriums, hotels and prisons. These efforts had limited success due to difficulties with product quality and high manufacturing costs. This paper describes the most recent innovations in HR technology which combines BASF's Rest Easy Plus HR foam technology with mixed isocyanate technology.

Raw Materials, formulations and foam properties for producing a variety of HR foam grades including all water blown super soft foam, HR latex foam, melamine modified HR foam and HR foam produced with mixed isocyanate are described. BASF feels that this technology has many strengths that will take it well into the twenty first century.

NovaFlex-Technologies in the Slabstock Industries: R. L. Kirschner, Hennecke Machinery, Dr. J. S. Pisipati, Bayer Corp., J. T. Ferrand, Bayer Corp., H. M. Sulzbach, Machinenfabrik Hennecke GmbH, Proceedings of the Polyurethane Foam Association, October 17 & 18, 1996.

Low density foam grades account for 70% of the market in the United States and about 25% of the market in Europe. The typical flexible foam slabstock plant has used auxiliary blowing agents such as methylene chloride in order to produce foam densities less than 2.0 pcf. The Clean Air Amendment of 1990 legislates a significant reduction in methylene chloride emissions. Compliance can be achieved by using alternative technology or capturing the blowing agent before emissions reach the atmosphere. Up to now, the search for a suitable replacement to produce low density furniture grade foams has not been resolved.

This paper describes the NovaFlex process, which facilitates the use of liquid carbon dioxide as an auxiliary blowing agent in polyurethane foam production. Information on the Hennecke NovaFlex process and production experience in Europe and the United States is discussed.

The NovaFlex technology offers several benefits to foam manufacturers including the following:

  • An environmentally acceptable blowing agent
  • Excellent foam quality
  • Potential for improved production economics
  • Combined equipment and chemical expertise

The Use of Polymer Additives to Achieve Optimal Physical Properties of Flexible Polyurethane Foam: V. C. "Jun" Fabella, Jr., Monsanto Company, Proceedings of the Polyurethane Association, May 16 & 17, 1996.

For some time now, foam produced with auxiliary blowing agents (ABAs) has been the benchmark of foam quality demanded by furniture manufacturers and their customers. New and pending local, state and federal environmental legislation are forcing flexible slabstock foam manufacturers away from use of some ABAs, especially methylene chloride.

Current technologies utilizing mechanical and chemical methods to produce foams without ABAs often produce foam of inferior quality. To overcome some of these physical property deficiencies, Monsanto is offering a new polymer modifier called Santofoam 1000.

This report covers the effects of Santofoam 1000 in flexible polyurethane foam. In brief, Santofoam improves the bulk physical properties in conventional flexible polyurethane foam formulations. Furthermore the use of Santofoam 1000 facilitates the removal of methylene chloride, an ABA.

Santofoam 1000 does not react with the isocyanate or the polyol. Santofoam 1000 becomes an integral part of the polymer system, and does not volatilize. Santofoam 1000 facilitates the polymerization (gelling) and the gas producing (blowing) reaction while ultimately improving and/or optimizing the physical properties of the foam.

New Principle of Pulverization of Flexible PUF Waste and Production of Flexible PUF Filled with PUF Powder: F. Shutov and T. Patel, Tennessee Technological University, Proceedings of the Polyurethane Foam Association, May 16 & 17, 1996.

Recycling of polyurethane foam (PUF) is becoming a major concern in most of the developed countries. In the United States, approximately 200 million pounds of flexible carpet underlay is made in these industries. It is estimated that 1,500 million pounds of post consumer foam was discarded in 1995 as products wear out or are salvaged.

The technology of pulverization of polyurethane scrap into a fine powder seems to be a promising route to recycle polyurethane foam. There are a number of processes for pulverizing PUF. Cryogenic grinding in which a very cold refrigerant (like liquid nitrogen) is employed to embrittle the material prior to grinding, was among the earliest methods to be studied. It requires substantial capital investment, and is therefor not very cost effective. The impact disk mill and two roll milling are some of the more recent non-cryogenic size reduction methods being studied.

The novel principle of pulverization of thermoplastic and thermosetting polymers, including PUF waste, is based on simultaneous action of high pressure and share deformation between mirror-like metal surfaces (called Bridgmen’s Effect). With the application of pressure, share and temperature at optimum proportion, the solid polymer can be successfully converted into material of high dispersity.

This paper deals with two novel pulverization, processes based on the Bridgmen’s Effect. The first is known as the Solid State Share Extrusion Process (SSSE), and the second as the Pressure Solid Pulverization Process (PSP). Using both the SSSE and PSP processes, a fine powder can be produced from flexible PUF waste. Powders having a particle size of 25-850 microns or 500-20 mesh are possible.

The powder produced from the scrap PUF can be used as a filler or reinforcing agent to improve the mechanical properties of the foam. As much as 30 percent of the PU powder can be added to the foam without adversely affecting it.

The authors conclude that this novel pulverization process offers an economically viable solution to the problem of recycling polyurethane foams.

Low Odor Catalysts for Flexible Polyester Foams: Robert L. Zimmerman, Robert A. Grigsby, Huntsman Corporation, Proceedings of the Polyurethane Foam Association, May 16 & 17, 1996.

The polyols used for the manufacture of polyester foams are made from diethylene glycol, glycerin and adipic acid. This gives a polyol with primary hydroxyl groups as opposed to polyether polyols, which have mostly secondary hydroxyl groups. As a result, polyester foams require different catalysts than polyether foams.

One difference is that polyester foams use up to ten times as much amine catalyst as polyether foams, therefore, odor becomes a much more important factor with polyester foams.

In this paper polyester foam catalysts are examined using the following criteria:

  1. Amount required
  2. Vapor pressure of the catalyst
  3. Foam discoloration
  4. Rise profile
  5. Cure profile

Low odor catalysts for polyester-based flexible urethane foams have been identified. These catalysts are highly efficient which not only helps to reduce odor but also helps reduce amine emissions from the foam plant. Foam cure is also affected by the catalyst, and it has been shown that good cure can be obtained while still maintaining a relatively low odor. Reaction profile can also be varied. Using this information, catalysts can be custom designed to meet individual requirements of a foam manufacturer.

Fire Dynamics: A Residential Perspective: Harrison Murphy, Ventex, Inc., Proceedings of the Polyurethane Foam Association, May 16 & 17, 1996.

The widening acceptability of full scale fire tests like California TB 129 for mattresses and 133 for furniture has made the determination of whether a product is open flame resistant quite scientific and clear. Either the product meets the peak rate of heat release requirement of the test or it doesn’t, and it fails.

There are barriers available which can significantly reduce the peak rate of heat release of residential mattresses and furniture. With such a barrier, a residential mattress, for example, would release only 35 KW as measure by the California TB 129 test, as compared to 2,000 KW without a fire barrier.

Fire barriers working in conjunction with unmodified and slightly combustion modified (117) foam can address the fire hazard at a minimal cost to industry and consumers. In addition, it can head off millions of dollars of liability suits that are inevitable under the current circumstances.

European Controversy Concerning Flammability Regulations for Furniture and Bedding, Dr. H. Creyf, Chairman Europur Technical Committee, Proceedings of the Polyurethane Foam Association, May 16 & 17 1996.

Europur has a number of reservations regarding some of the conclusions and recommendations of the CBUF Report, however, they feel it represents a major step forward in fire science. CBUF themselves indicate the need for further model development and for cone calorimeter proceedures to be tried by more laboratories, and to be used over a broader range of materials.

The author concludes that the PU industry is concerned about the safety of consumers as well as the benefits they receive from polyurethane products. He also feels that the CBUF research is a major contribution to our understanding of the flammability of furniture, but cannot be accepted in its present state as a basis for further legislation or the development of CEN standards. Finally he feels that the PU industry believes that a consumer demand driven increase in the use of cigarette resistant furniture coupled with an increase in the use of smoke detectors is the best way to have an impact on domestic furniture fires.

The Combustion Behavior of Upholstered Furniture (CBUF) an American Perspective: T. Hugh Tally, AFMA, Proceedings of The Polyurethane Foam Association, May 16 & 17, 1996.

The author reviews the CBUF study and comes to the following conclusions:

1. "While the CBUF program advances our understanding of fire science, and our ability to evaluate and predict the burning behavior and fire hazards of upholstered furniture, much work remains to be done to substantiate the postulates providing the foundation for the work (e.g. ignition sources and detectability limits), the test protocols, computer models, and the reported conclusions."
2. The conclusions drawn and methodologies used are certainly not ready for use in any regulatory manner.

Recent Developments in Stabilizers for Flexible Polyester Polyurethane Foam: Eddie Silman, Dr. Volker Zellmer, Hans-Heinrich Schlons and Rainer Ziegler, Goldschmidt AG, Proceedings of the Polyurethane Foam Association, May 16 & 17, 1996.

Flexible polyester polyurethane foam represents a small but important part of the flexible foam market because of outstanding properties such as high hardness, tensile strength, elongation, resistance to oxidation and solvents, die cutability, and the fact that it is flame laminable to textiles. These characteristics are essential for the automotive, textile, and household industries where, in special application, ester foam provides advantages over polyether polyurethane foam.

As in other polyurethane foam systems, the stabilizer is a key ingredient in the production of polyester foam. In addition to the required physical stabilization, ester surfactants should also provide regular cell structure without any pin holes, control cell size and foam breathability, and should not have a negative effect on foam combustibility. The stabilizer should also allow the production of die cutable foams, with or without the use of additives such as paraffin oil.

The objective of this work was to identify how each of these different foam properties correlate to the individual structural parameters of a silicone based foam stabilizer. Based on this data, a new stabilizer was developed with well defined and superior properties for the current market requirements. The performance of this new, more universal surfactant is also described. It can be used across a broad range of formulations with a large operating window of production safety.

A Novel Approach to Antioxidant Dissolution in Polyols: Robert L. Gray, E. Lee, Brent M. Sanders, Great Lakes Chemical Corporation, Proceedings of the Polyurethane Foam Association, May 16 & 17, 1996.

Work continues to be done to provide effective stabilization of polyols used for flexible bun stock production as a result of the increased exotherm resulting from the reduction of chlorofluorocarbon (CFC) blowing agents and the associated increase in water content of these formulations. BHT shows outstanding performance in scorch inhibition. However, its high volatility can lead to problems with fogging and the formation of highly colored by-products. This paper describes several lower volatility alternatives, which can be used in place of BHT.

Several lower volatility alternatives to BHT were evaluated using a microwave scorch test, which has been used in the laboratory to reproduce the thermodynamics of large production foams. The importance that antioxidant solubility in polyol has on scorch resistance has already been demonstrated in the laboratory. Two antioxidants, AO2 and AO3 show good performance and are liquids and miscible in polyol. The least volatile and more effective phenolic antioxidant is AO5. The amorphous form of AO5 dissolved in standard polyol is 20 degrees centigrade lower than the crystal form. This represents a significant advantage in energy savings and worker safety.

It is important to keep in mind that the results reported in this study were developed in a laboratory setting where the actual conditions of industrial scale production may not be accurately represented.

Assessment of Potential Health Risks Resulting from Chemical Emissions from New Bedding Sets: Sponsored by The Sleep Products Safety Council, Proceedings of the Polyurethane Foam Association, May 16 & 17, 1996.

In response to adverse television publicity about alleged health effects from newly purchased mattresses, the Sleep Products Safety Council (SPSC) sponsored research to evaluate the potential health effects from chemical emissions from newly manufactured bedding sets.

Bedding sets representative of a high percentage of those commonly sold in the U. S. were evaluated for chemical emissions in a series of controlled laboratory test performed by Research Triangle (RTI). Individual components from each of the bedding sets were also tested by TRI. A hazard and risk assessment of the RTI emissions measurements by Versar Inc. showed no acute inhalation, dermal or odor health risks associated with the short-term exposure to mattress emissions, at the rates measured by RTI, for normal or convalescing individuals. This study was performed with the counsel and review of an independent Scientific Review Board composed of eminently recognized environmental and health scientists.

The Beamech CO-2 Process for the Continuous Manufacture of Flexible Slabstock Foam: J. Brian Blackwell, Beamech Group Ltd., Proceedings of the Polyurethane Foam Association, May 16 & 17, 1996.

Recently liquid CO-2 has been promoted and used successfully to completely eliminate CFC’s and regulated VOCs from the production of flexible slabstock foam. In recent months, more manufacturers have announced the availability of equipment for the production of flexible slabstock foams using liquid CO-2 technology. The Beamech group have just entered the market with equipment for metering and mixing liquid CO-2 under high pressure to produce a stable froth which can be used to produce low density flexible slabstock foam. This paper describes their equipment and process.

Silicone Surfactant Effects on Cell Structure in Liquid CO-2 Blown Slabstock Foams: Rob Borgogelli, Frank Carey, and Dr. Volker Zellmer, Goldschmidt Chemical Corp., Proceedings of the Polyurethane Foam Association, May 16 & 17, 1996.

Since the introduction of liquid CO-2 blown slabstock foams to the flexible polyurethane industry, Goldschmidt has been actively engaged in the production of foams by these new processes. Early development stage research continues to create new products designed specifically for liquid CO-2 blown flexible foam surfactants. It focuses primarily on observations from trials of existing and experimental products on U. S. foam production equipment. Data from laboratory techniques developed by Goldschmidt that seem to correlate well to industrial experience is also reported.

The results of this study indicate that Goldschmidt’s BF 2370 still appears to be the product of choice to achieve fine regular cell structure with a minimum of pinholes and voids. EP-H-101 provides higher stabilization than BF 2370, and may be useful for achieving finer cell size in certain formulations.

With respect to universal surfactants, EP-H-100 appears to provide a finer cell structure than B 8228 in most CO-2 systems. In comparison to BF 2370, the higher potency and improved flammability performance of EP-H-100 makes it an ideal candidate for the U. S. market. Research continues to develop experimental surfactants that provide improved performance for this technology.

Two Years of Industrial Experience with liquid CO-2 Blown Slabstock Foam: Heinz Meloth, Cannon USA, Proceedings of the Polyurethane Foam Association, May 16 & 17, 1996.

This paper presents the results of two years of industrial use of CarDio (TM), Cannon Group’s proprietary technology for producing liquid CO-2 blown flexible slabstock foam The range of foam densities obtainable using this technology along with foam quality, processing aspects and its economies are illustrated.