Flexible Slabstock Foam Research Articles

Birth of PU foam technology

Cannon Viking is celebrating the 30th anniversary of its CarDio sustainable liquid CO2 blowing agent technology which produces polyurethane (PU) flexible slabstock foams.

Influence of the use of recycled polyols obtained by glycolysis on the preparation and physical properties of flexible polyurethane

AbstractPolyurethanes (PUs) represent one of the most important groups of plastics, and so the increasing quantity of wastes makes their recycling an urgent task. The general purpose of PU chemical recycling is to recover constituent polyol, a valuable raw material. Among the suitable processes, glycolysis in two phases allows better quality products. The objective of this work is the evaluation of the option to apply the recovered polyols to obtain PU with identical characteristics to the starting raw material, and so several foaming tests were carried out according to the evaluation method employed in free expansion foaming of conventional flexible slabstock foams. To achieve this objective, a formulation recipe for flexible foams was selected, in which the raw polyol was totally or partially replaced for recovered polyol. The foaming formulations were modified because of the different amount of active hydrogens in the recovered polyols and the virgin polyol. Amounts up to 50% could be applied without relevant changes in rising profiles and the physical properties of the foams. The foams were characterized, and according to its appropriate characteristics they can be employed in the same applications where a commercial one made with raw polyol is used. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

Impact of Silicone Surfactants on the Flammability of Flexible Slabstock Foam – Comparison of California TB 117/draft 2002 with Established Flammability Tests

It is well known that silicone surfactants have an influence on the flammability of the manufactured foam. Generally silicone surfactants have a negative impact on flammability, e.g., higher levels of flame-retardants (FRs) are necessary to pass the required FR test. During the recent years, Degussa has put a lot of resources into the development of optimized chemical structures that have a minimal impact on flammability. The challenge is to make these changes without impacting other key properties, like stabilization potency and processing latitude. In early 2002, the State of California proposed a change to the old CAL TB 117, the industry flammability standard for furniture foam in the US since 1975. Even though it is still in draft form (no final decision on roll-out date and exactcontent has been made), the optimization of formulations with respect to FR-properties will be one of the key technical issues for all foamers supplying to the US furniture industry. This paper deals with the evaluation of universal and FR-surfactants concerning their contribution to flammability as well as other performance characteristics. The CAL TB 117/draft 2002 will be applied as well as CAL TB 117/march 2000, MVSS 302, ASTM 1692, and BS 5852 (Crib 5). It will give guidance to foamers on how to minimize the flammability of their foams with the correct choice of the silicone surfactant.

Closed Loop of Polyurethane Flexible Slabstock Foam Wastes by a Chemical Process

Presently, about 8 million metric tons of polyurethanes are produced in the world annually. During production of precursors, semi-finished products and final products about 5 to 10 % of this amount is waste, i. e. an amount of about half a million tons. To this add the products after their life cycle. This is a large source of material which should not be given to landfills or incinerators but be used as secondary materials for the production of new polyurethanes.

New Catalysts for Low VOC in Flexible Slabstock Foam

Until recently it was only the automotive industry that demanded a serious reduction of the amount of volatile organic compounds (VOC) from the (usually molded) polyurethane foam which is being used in their products. Now the end-users of bedding, furniture and carpet backing foam have joined them, and this time the pressure is on the manufacturers of flexible slabstock foam. It is for this reason that Nitroil Performance Chemicals have investigated if the solutions developed by this company for the molding area can also be applied to conventional slabstock. The main sources of VOC were additives like silicone surfactants and amine catalysts. For HR molding Nitroil evaluated a series of reactive amines in comparison to industrial standard amine catalysts such as triethylenediamine and bisdimethylaminoethylether. It appeared that by using only reactive amines the mine emission could be eliminated, and the total VOC could be reduced by 50% for TDI-based formulations and by 80% for MDI-based ones. Laboratory...

Liquid Carbon Dioxide Foaming in Flexible Slabstock Foam Production—A Challenge to be Met with New Structural Building Blocks

The introduction of liquid carbon dioxide foaming into the production of polyurethane foams a few years ago created a challenge for the whole industry. That is true for the equipment as well as for the raw material suppliers-and especially so for any additive supplier. The new foaming technology created a demand for processing conditions and ingredients that would meet the challenge of providing the additional nucleation required without sacrificing other important performance aspects. The important role of the surfactant used has been recognized even with the start of this future-shaping technology. This alone justified a higher interest in the questions "How do the different structural parts of a surfactant molecule influence its performance?" and "Which structural pattern is useful for the controlled design of surfactant performance for the new level of nucleation needs?" To keep other vital performance aspects, these structural patterns then have to be combined with the polydimethylsiloxane-polyether-copolymer structure of foam surfactants commonly utilized today which are mainly based on a combination of just three structural units: the methyl substituted siloxane backbone as well as a sophisticated combination of ethylene oxide and/or propylene oxide forming the attached polyethers. This paper will describe our work in the liquid carbon dioxide field and the resulting structure-performance relationships of flexible slabstock polyurethane foam surfactants. It will also link those structure-performance relationships to different possible applications like fr-or non-fr-foams. A number of building blocks will be introduced for the novel design of these performance additives. Especially in view of further industrial trends, these novel structural units should open up the possibility for new foam surfactants with adjusted and improved performance profiles.

Factors Influencing the FR-Performance of Polyurethane Slabstock Foams

The ever increasing amount of legislation on fire performance tests in many parts of the world indicates the decisive roll of FR-performance on the further development of the polyurethane-foam business in general. Because of this, the use of flame retardants is imperative for many applications but attempts were made to evaluate other factors which also influence the FR-performance of the polyurethane foam, as well. The focusing point of our work was the question whether there are practical ways to implement results into actual production processes. For example the influence of foam porosity on FR-performance is well known. Nevertheless, it may not be a factor to be changed under production conditions due to foam specifications. In this paper research will be shown regarding the question in which way FR-performance and production safety can affect formulation changes without changing foam porosity. Other topics of special interest to us are the melting performance and the influence of surface morphology on the burning of flexible slabstock foam. This also relates to the use of fillers in slabstock formulations and their effects on the flammability of foams. Another important aspect that has been considered is the influence of the silicone surfactant structure, especially with regard to the ethylene oxide content of the utilized polyethers in the surfactant. The dependence among silicone surfactant structure, the amount of silicone surfactant within a foam and the resulting influence on FR-performance is another very important aspect to consider for optimum FR-properties. Differences between the use of conventional, universal and FR-surfactants will be shown and explained. Based on the results of our work the parameters to design surfactants with enhanced FR-performance will be discussed.

Characterization of flexible slabstock foams containing lithium chloride

AbstractCharacterization of a series of flexible polyurethane foams that contain LiCl in their formulation is discussed. These foams were developed in order to provide an alternative method to produce foams without physical blowing agents and still attempt to maintain specific important physical properties. Three high water content foams of varying LiCl content have been characterized by utilizing several morphological techniques as well as by their viscoelastic behavior. From a morphological standpoint, it appears that by adding LiCl to the formulation, there is less formation of urea‐rich aggregates that occur when LiCl is absent. Also, the hard segments are more dispersed as single units within the network. The cellular texture of the LiCl‐containing foams also shows a greater amount of cellular window material than the same foam without LiCl. Both of these changes due to LiCl addition are believed to bring about a significant increase in the amount of viscoelastic decay. This decay has been observed in tensile stress relaxation, compression load relaxation, and compressive creep studies. Temperature also has a more significant effect on the compression load relaxation behavior of foams with LiCl in their formulation than when absent. These differences in viscoelastic behavior between foams with and without LiCl in their formulation are attributed to the greater mobility of the hard segments in the presence of the LiCl additive serving as a localized “hard segment” plasticizer that also promotes more phase mixing in the foams. © 1994 John Wiley & Sons, Inc.

Novel Technology for the Manufacture of All Water-Blown Flexible Slabstock Foam

Novel Technology for the Manufacture of All Water-Blown Flexible Slabstock Foam

Combustion behaviour of fabric and polyurethane flexible foam mock‐up combinations under Cone Calorimetry test conditions

AbstractThe relative contributions of fabric and foam on important fire hazard parameters as measured in the cone calorimeter were determined for various mock‐up combinations. Three commercial types of high‐resilience PU flexible slabstock foams, representing a wide range of combustion performance, were combined with three different fabrics: polyester, polypropylene and combustion‐modified cotton. Total heat release of the combinations correspond well with the value calculated from the individual components and is determined by the density and effective heat of combustion of the components, and the foam/fabric weight ratio. The foams show a smaller variation in effective heat of combustion than the fabrics. Covering of PU flexible foams with a fabric results in general in a delay of ignition and peak rate of heat release. Performance of the mock‐ups is mainly determined by the fabric but is also influenced by the quality of the foam.

New Developments in Silicone Surfactants and Amine Catalysts for Flexible Ester Slabstock Foam

New Developments in Silicone Surfactants and Amine Catalysts for Flexible Ester Slabstock Foam

Combustion Behaviour of Fabric and Polyurethane Flexible foam Mock-up Combinations under Cone Calorimetry Test Conditions

The relative contributions of fabric and foam on important fire hazard parameters as measured in the cone calorimeter were determined for various mock-up combinations. Three commercial types of high resilience PU flexible slabstock foams, representing a wide range of combustion performance, were combined with three different fabrics; viz. polyester, polypropylene and combustion modified cotton. Total heat release of the combinations correspond well with the value calculated from the individual components and is determined by the density and effective heat of combustion of the components, and the foam/fabric weight ratio. The foams show a smaller variation in effective heat of combustion than the fabrics. Covering of PU flexible foams with a fabric results in general in a delay of ignition and peak rate of heat release. Performance of the mock-ups is mainly determined by the fabric but also influenced by the quality of the foam.

Polyol Technologies to Reduce or Eliminate Use of CFCs in Flexible Slabstock Foams

The purpose of this paper is to provide an update on technology developments that demonstrate feasible alternatives to the manufacture of CFC and halogenated ABA flexible polyurethane foams. A number of approaches will be presented along with a discussion regarding how they can be used by foam producers to reduce or eliminate the need for these materials

New Developments in Silicone Surfactants and Amine Catalysts for Flexible Ester Slabstock Foam

New Developments in Silicone Surfactants and Amine Catalysts for Flexible Ester Slabstock Foam

Optimizing Amine Catalyst Levels in Flexible Slabstock Foams

Optimizing Amine Catalyst Levels in Flexible Slabstock Foams

Flexible Polyurethane Slabstock Foam: The Influence of Formulation, Climatic Conditions and Storage Conditions on Foam Properties

Flexible Polyurethane Slabstock Foam: The Influence of Formulation, Climatic Conditions and Storage Conditions on Foam Properties

The Effect of Monohydroxy Polyether Polyols On the Processing, Reactivity, and Physical Properties Performance of Flexible Slabstock Foam Systems

This article reports on work which shows that as the level of monohydroxy polyether polyol was increased from 0.01 to 0.09 meq/gram, foam physical properties are not adversely affected. At levels of monohydroxy polyether polyol greater than 0.09 meq/gram, the loadbearing values show a significant downward trend.

Improved Load Bearing in Flexible Slabstock Foams

Improved Load Bearing in Flexible Slabstock Foams

Methylene Chloride Urethane Grade As a Viable Auxiliary Blowing Agent In Flexible Slabstock Foam

Methylene Chloride Urethane Grade As a Viable Auxiliary Blowing Agent In Flexible Slabstock Foam