Slabstock Foam Research Articles

Waste-to-energy: Repurposing flexible polyurethane waste for triboelectric nanogenerator applications

Triboelectric Nanogenerators (TENG) is a promising approach for clean energy harvesting. Light weight, flexible, cheap and environmentally-friendly materials are being explored as potential components in the TENG device in order to increase its efficiency. This paper reports the first effort to successfully utilize rebonded flexible polyurethane (RFPU) waste as a tribopositive material in a TENG device. A batch moulding technique was used to create two different densities (60 and 70 kg/m3) of flexible polyurethane (FPU) scraps, including customer waste and slabstock foam production waste. The current study investigates the effect of density on the compression strengths of the RFPU materials, as well as the impact on the output voltage of the TENG. Additionally, the effect of various RFPU sheet thicknesses (2, 4, 6, and 8 mm) as well as the effect of different applied forces and frequencies on the TENG's output voltage were investigated. The findings showed that the compressive strength increases with higher RFPU density. The output voltage values of the TENG device were recorded both with and without pre-charging. The results, without pre-charging, revealed that the highest output voltage of the TENG was obtained using an RFPU sheet with a density of 60 kg/m3. Furthermore, output voltage was shown to decrease with increasing RFPU sheet thickness and to increase with applied frequency. Pre-charging showed a similar trend, but yielded better results compared to the RFPU samples that were not pre-charged. The power density peaked at 0.085 mW/cm2, at a load resistance of 5 MΩ and a force of 4.7 N. The RFPU-based TENG successfully powered four white LEDs connected in series. Analysis of the embodied energy associated with using PU foam waste instead of virgin PU foam was conducted and demonstrated that utilizing PU foam waste provides environmental benefits due to the significant contribution of raw materials to the overall embodied energy in PU foam that is saved when reusing foam waste. Additionally, assessing the embodied energy of the components of the TENG device was also conducted and shows that the generated energy can partially offset the embodied energy of the TENG device. As a result, the prepared RFPU material not only helps to safeguard the environment but also shows great promise for use in developing more efficient and affordable TENGs in the future.

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.

Occupational Exposure to Diisocyanates in the European Union.

ObjectivesDiisocyanates are a chemical group that are widely used at workplaces in many sectors. They are also potent skin- and respiratory sensitizers. Exposure to diisocyanates is a main cause of occupational asthma in the European Union. To reduce occupational exposure to diisocyanates and consequently the cases of diisocyanate-induced asthma, a restriction on diisocyanates was recently adopted under the REACH Regulation in the European Union.MethodsA comprehensive evaluation of the data on occupational exposure to the most important diisocyanates at workplaces was made and is reported here. The diisocyanates considered are methylene diphenyl diisocyanate (MDI), toluene diisocyanate (TDI), and hexamethylene diisocyanate (HDI), accounting for more than 95% of the market volume in the EU. The exposure assessment is based on data from Chemical Safety Reports (CSRs) of REACH Registration Dossiers, workplace air monitoring data from Germany, from the UK Health and Safety Executive (HSE), and literature data relevant for the EU, and the USA.ResultsOccupational exposure to diisocyanates is particularly relevant in: (i) C.A.S.E. applications (Coatings, Adhesives, Sealants, Elastomers), (ii) production of polyurethanes (PUs) (e.g. slab-stock foam), (iii) handling of partly uncured PU products (e.g. cutting, demoulding, spray application of foam), and (iv) when diisocyanates/PUs are heated (e.g. hot lamination, foundry applications/casting forms). Ranking of the reported data on inhalation to diisocyanate exposure at workplaces (maximum values) leads to following order: (i) HDI and its oligomers in coatings, (ii) MDI in spray foam applications, (iii) TDI in manufacture of foam, (iv) TDI in manufacture of PUs and PU composite materials, (v) TDI in adhesives, (vi) MDI in adhesives, (vii) MDI in manufacture of PUs and PU composite materials, (viii) TDI in coatings, (ix) MDI in manufacture of foam, and (x) HDI in adhesives.

Shedding new light on polyurethane degradation: Assessing foams condition in design objects

A new insight into the degradation of polyurethane (PUR) slabstock foams is suggested by studying historical design objects and PUR references submitted to natural ageing. PUR foams are segregated structures comprising hard and soft domains, as well as chemical and physical crosslinking (H-bonds). H-bonds have been commonly followed in polymerisation studies of PUR foams by monitoring carbonyl bands in the infrared. Their fundamental role in PUR physical properties has been stressed; however, their liability to natural ageing has been poorly focused, with few studies suggesting their vulnerability to high temperature and humidity. As PUR has a short lifespan, and many objects show severe degradation signs (yellowing, crumbling and brittleness), the in-depth analysis of PUR foams behaviour upon natural ageing, as well as the monitoring of H-bonds over these processes is discussed in this paper. References of PUR slabstock foams (ether-based polyols and toluene diisocyanates) were produced; and infrared micro-spectroscopy and optical microscopy (under darkfield, polarised light and UV light) were selected to assess PUR ageing. A visual (micro level) and molecular pathway for PUR natural ageing is suggested, and deterioration signs (yellowing, micro holes, pitting and cracks) on PUR cell buns were translated into specific infrared fingerprints (assigned to N–H, C–H and C=O stretching absorptions). As the C=O band at c. 1640 cm−1 (indicator of PUR hard domain ordered structure) showed considerable changes upon PUR ageing, this study confirms H-bonds as liable to natural ageing, and proposes this band as marker of ether-based PUR slabstock foam condition.

Natural Oil Polyol (NOP) Based Polyurethane Slabstock Foam for Automotive Interior Foam-Fabric/Vinyl Laminate Construction

Natural Oil Polyol (NOP) Based Polyurethane Slabstock Foam for Automotive Interior Foam-Fabric/Vinyl Laminate Construction

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.

Fate and Potential Environmental Effects of Methylenediphenyl Diisocyanate and Toluene Diisocyanate Released into the Atmosphere

Information from a variety of sources has been collected and summarized to facilitate an overview of the atmospheric fate and potential environmental effects of emissions of methylenediphenyl diisocyanate (MDI) or toluene diisocyanate (TDI) to the atmosphere. Atmospheric emissions of both MDI and TDI are low, both in terms of concentration and mass, because of their low volatility and the need for careful control over all aspects of their lifecycle from manufacture through disposal. Typical emission losses for TDI are 25 g/t of TDI used in slabstock foam production. MDI emission losses are lower, often less than 1 g/t of MDI used. Dispersion modeling predicts that concentrations at the fenceline or beyond are very low for typical releases. Laboratory studies show that TDI (and by analogy MDI) does not react with water in the gas phase at a significant rate. The primary degradation reaction of these aromatic diisocyanates in the atmosphere is expected to be oxidation by OH radicals with an estimated half-life of one day. Laboratory studies also show that this reaction is not expected to result in increased ground-level ozone accumulation.

Influence of lithium chloride on the morphology of flexible slabstock polyurethane foams and their plaque counterparts

In continuing efforts to understand urea phase connectivity in flexible polyurethane foams and its implications on physical properties, LiCl is used to alter the phase-separation behavior of slabstock foams. Comparisons are also drawn with plaque counterparts, which are prepared using the same polyol, isocyanate, and chain extender (water). LiCl is shown to alter the solid-state phase separation behavior of the foams and the plaques in a similar manner. This is confirmed using multiple characterization techniques, which provide information at different scale lengths. The foams and plaques with and without LiCl are shown to possess a microphase separated morphology with interdomain spacings of ca. 100 Å. SAXS and TEM reveal that addition of LiCl reduces the urea aggregation behavior, typical in slabstock polyurethane foams, leading to a loss in the urea phase macro connectivity. Hard segment ordering, as studied by WAXS and FTIR, is shown to be of a similar nature in the plaque and foam, which do not incorporate LiCl. Addition of LiCl leads to a loss in the segmental packing behavior, or micro level connectivity of the urea phase, in both the plaques and corresponding foams, as inferred from WAXS and FTIR. The LiCl additive interacts with the polyol soft segments in an insignificant manner as shown from FTIR and DMA. In addition, foams containing LiCl are found to possess more intact cell windows due to the influence of LiCl on reaction kinetics as well as its effect on the precipitation of the urea phase. The experimental observations are supported by quantum mechanical calculations using a density functional theory approach, where molecular interactions between LiCl and model ether, urethane, and urea compounds are investigated. Interaction geometries of most stable complexes and their stability energies are calculated. Stability energies of ether/LiCl, urethane/LiCl, and urea/LiCl were determined to be −189, −617, and −687 kJ/mol, respectively, reinforcing that LiCl interacts predominantly with urea hard segments and in a minimal manner with the polyol soft segments.

DBTDL Replacement in High Resilience Slabstock Foams

Over the last two years, serious concerns have been expressed in the press about human exposures to trace amounts of alkyl tin moieties such as tributyltin (TBT). Organostannic compounds are commonly used as catalysts in polyurethane chemistry. Whereas stannous octoate (SNOCT) exhibits a TBT content below the detection limit of most analysis equipment (< 0.01%), TBT levels as high as 0.6% have been measured in dibutyltin dilaurate (DBTDL). Although DBTDL manufacturers are currentlyoptimising their process to lower the TBT content in DBTDL, the (chemo) pressure exerted on polyurethane foamers is such that DBTDL-free formulations are being activelylooked for. High resilience (HR) foams based on various polymer polyols–particularly polyols made with pure polystyrene (POSTech*) or poly(styrene–acrylonitrile)–have been developed using DBTDL as the gel catalyst. The direct replacement of DBTDL is not straightforward, as foam block dimensional stabilityissues (often referred to as “cold flow”) are encountered when other catalyst (i.e., SNOCT) are used. This “cold flow” phenomenon is verymuch dependent on the size and the weight of the foam block produced, making all small scale laboratory experiments unsuitable for developing novel stable HR foam formulations. The present research has shown that properties derived from small scale experiments can nevertheless be related to the “cold flowability” of HR formulations. Amongst the various tests investigated, the variation in sag factor from top to bottom of the foam block was found to be the most relevant test method to assess the dimensional stability. Sag factor is here defined as the force exerted bythe foam compressed to 65% of the original thickness divided by that exerted at 25% compression during the compression load deflection (CLD) test. The test method based on this variation in sag factor through the foam block (vSag) made possible the laboratoryexamination of formulation parameters for their impact on foam block stability. It also allowed us to develop a wide density range of POSTech-based DBTDL-free HR slabstock foams that are dimensionallystable.

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...

Low Resilience Polyurethane Slabstock Foam with Microphase Separated Morphology

Low Resilience Polyurethane Slabstock Foam with Microphase Separated Morphology

Low Resilience Polyurethane Slabstock Foam with Microphase Separated Morphology

The purpose of this paper is to elucidate the nature of the low resilience foam with microphase separated morphology. Takeda has developed a unique homogeneous polyol mixture, which provides a low resilience foam with two glass transition temperatures. The existence of two tan 8 peaks, a glass transition and P glass transition around -40°C and room temperature, respectively, indicates the presence of the microphase separation. The chemical structure and the reactivity of the homogeneous polyol is well designed for the simultaneous formation of the heterogeneous morphology during the blowing process. The newly developed foam did not increase its hardness in the range of 0 to -20°C and did not become glassy even at -20°C; the storage modulus curve has a plateau region around -10°C. The a glass transition temperature was sensitive to the formulation factors, polyol ratio, water level, index and plasticizer, whereas the f glass transition temperature is less sensitive to those factors.

Surfactant level influences on structure and properties of flexible slabstock polyurethane foams

A series of flexible polyurethane slabstock foam samples were prepared with varying surfactant concentration. Several samples were also prepared by quenching small pieces into liquid nitrogen during the foaming process. The morphology of these materials was characterized at many length scales via scanning electron microscopy (SEM), transmission electron microscopy (TEM), wide-angle and small-angle X-ray scattering (WAXS and SAXS), tapping-mode atomic force microscopy (AFM), and Fourier transform infrared spectroscopy (FTIR). AFM was also utilized to probe trends in the mechanical stiffness of hard domains in the polyurethane foam. Differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) were applied to examine the thermal and viscoelastic properties of these foams. It was shown in this study that collapse of the cellular structure of a foam prior to the point of urea precipitation alters the aggregation behavior of the hard domains and influences their ultimate properties. Samples without surfactant quenched in liquid nitrogen exhibited urea-rich aggregations on the order of 2–4μm with similar sized urea-poor regions. Equivalent samples with surfactant showed no such aggregations, suggesting that surfactant does play a principal role in the way that urea precipitates in these materials. DMA and DSC revealed that all samples of any surfactant concentration which spontaneously collapsed or were quenched or crushed prior to completely curing had a polyol glass transition 3–5° higher and somewhat broader than any foam sample which maintained its cellular structure until cured. This is interpreted to mean that the polyol matrix of the collapsed, crushed, or quenched materials is not as pure as the cellular samples, indicating that the presence of the cellular morphology plays a significant role in the microphase separation behavior of the solid-state at the molecular level. This hypothesis is supported by the results of WAXS, FTIR, SAXS, and AFM. The WAXS results demonstrate that at no surfactant concentration is the ordering, or hydrogen bonding, within the hard domains being significantly altered; however, in the lower range of the concentrations studied here, the FTIR results show that the surfactant level in the formulation does play a significant role on the amount of bidentate hydrogen bonded hard domains that organize locally. Further, as shown by SAXS, the surfactant concentration influences the mean chord length across the hard domains. These changes in structure and domain size distribution lead to the properties investigated via AFM, where the relative hardness of the hard domains was noted to initially increase as the surfactant concentration increases and then levels off above a certain concentration. The surfactant is thus suggested to play a secondary role in the development of the hard domains by maintaining the cellular structure in the foam as the phase separation occurs and at least until the polyurethane foam has more fully organized hard segment domains.

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.

Urea hard segment morphology in flexible polyurethane foam

A series of flexible polyurethane slabstock foam samples were prepared with varying water content and studied using transmission electron microscopy (TEM), video-enhanced optical microscopy (VEM), and small-angle X-ray scattering (SAXS). A new TEM sample preparation technique was developed in which the foam is impreg- nated with water, frozen, and microtomed, and the polyether soft segment is selectively degraded in the electron beam. Structures of two size scales were detected. A texture with grains (''urea aggregates'') 50-200 nm in size was imaged using both VEM and low-magnification TEM for foams with formulations containing more than 2 pphp wa- ter. For the first time, images of urea hard segment microdomains in polyurethane foam (approximately 5 nm in size) were obtained using high-magnification TEM. A microdomain spacing of approximately 6-8 nm was estimated from the SAXS scattering profiles. Glycerol was added to one of the formulations in order to modify the urea microphase separation and to give insight into morphology development in molded polyurethane foam systems. No structure was observed in low-magnification TEM im- ages of the glycerol-modified foam, although smaller structures (hard segments) were detected at high magnification and by SAXS. q 1998 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 36: 573-581, 1998

Antioxidant Systems for Stabilization of Flexible Polyurethane Slabstock Foams

The flexible slabstock polyurethane foam industry has been undergoing regulatory changes in recent years. The mandated reduction in halogenated blowing agents (CFCs) has profound implications for the development of adequate heat stabilization systems for the slabstock foam. Increased bun temperatures and concomitant scorching can result when CFCs are not present to assist in heat removal from the bun. Newer forced cooling processes (blown air or carbon dioxide) still incur high bun temperatures, and the possibility exists for loss of volatile stabilizer additives which could result in bun scorching and discoloration. The historical, and still prevalent stabilization approach utilizes BHT as a primary phenolic antioxidant, with an alkylated diphenylamine as co-stabilizer in some cases. However, the volatilization and loss of BHT from slabstocks during manufacture is known, resulting in inadequate bun stabilization, staining, etc. Consequently, antioxidant strategies utilizing lower volatility additives still are sought that inhibit the free radical, autocatalytic mechanisms of degradation. This paper will review and contrast traditional stabilization strategies for polyols and flexible foam polyurethanes. Emphasis on lower volatility antioxidant replacements for BHT will be discussed. Data to be presented include thermal analysis (DSC, OIT) testing of polyols and flexible foams. Since color evaluations in scorched foams have been related to the effectiveness of the stabilization system used, these data will be discussed for polyurethane foams that were prepared in the laboratory and subjected to microwave oven scorch testing.

Structure-property relationships of flexible polyurethane foams

In this study the viscoelastic and compression set properties were studied as a function of temperature and humidity for a series of moulded foams based on toluene diisocyanate (TDI) and glycerol initiated ethylene-oxide-capped propylene-oxide. The results were compared to those obtained on conventional slabstock foams based on TDI and glycerol initiated propylene-oxide. These comparisons were made to delineate and clarify distinct differences between these two different but very important systems. It was found that high temperatures and humidities ‘plasticized’ the moulded foams to a greater extent than the slabstock foams. Moulded foams displayed a higher compression set value and higher load decay value in the viscoelastic measurements than slabstock foams. In an attempt to understand these dramatic differences, the two types of ‘cross-links’ (covalent cross-links and urea-based phase separated hard segment domains) were more directly compared. It was found that the hard segment domains in the slabstock foam had a much higher level of short range ordering and cohesiveness. This was first confirmed by comparing the wide-angle X-ray scattering (WAXS) patterns where the amorphous character was much more pronounced in the moulded systems of equal water/TDI content. The WAXS behaviour of the slabstock system distinctly displayed short range ordering of the TDI based units. Second, Fourier transform infrared ( FTi.r.) data from the carbonyl region showed that the slabstock foam had a much higher level of bidentate urea (strong hydrogen bonding) within the hard segments. Conversely, the moulded foam displayed no bidentate urea but only monodentate urea or weaker hydrogen bonding within the hard segments. This is not to imply that microphase separation did not occur since small angle X-ray scattering (SAXS) clearly showed evidence of a phase separated morphology for both types of foam systems. It is thus concluded that the dramatic differences between the mechanical properties of moulded and slabstock foams are due in part to differences in the covalent network but mostly due to the lower and weaker ordering of the hard segments in moulded systems making these physical cross-links more labile at higher temperatures and humidities. These morphological differences are believed to be due primarily to two differences in the formulation components and processing between the two studied systems. First, the ethylene-oxide capping used in the polyol of moulded foams to increase the reactivity is known to also increase the compatibility between the hard and soft segments. Second, the addition of diethanolamine (DEOA) added in the moulded foam formulation to decrease demould times by enhancing more rapid cross-linking has been shown to prevent the full local packing development of the hard-segment domains (physical cross-links).

A New Era for MDI: Flexible Polyurethane Slabstock Foam

In the past few years, much effort was put into developing new technologies for high resilience (HR) slabstock foam applications involving the use of MDI-based prepolymers. The main advantages claimed were better feel of the foam and enhanced physical properties over standard HR foams. However, those HR technologies have been developed to be used in the high quality HR market segment at densities generally ranging from 2 to 4 lb/ft3. Little work has been reported so far in the area of conventional slabstock foams produced with MDI, i.e., using high potency surfactants and polyols with secondary hydroxyls. By carefully selecting the MDI component, it has been possible to manufacture slabstock foams at densities ranging from 3 to 1.5 lb/ft3 with acceptable processing latitude. The main advantage of those foams over TDI based ones are: (1) the possibility to make very firm foams without the need for any filler, (2) the use of low vapor pressure MDI, (3) very fine cell structure and resulting good feel of the foam, (4) very fast skin curing and final curing and (5) the possibility to manufacture non-shrinking low breathability foams. The challenges for these MDI-based foams include the lower NCO% of MDI, poorer blowing efficiency relative to TDI, compromised mechanical properties and narrow processing latitude, which may be a concern at the lowest densities especially on trough-like machines. This paper will discuss the influence of the nature of the isocyanate upon the formulation parameters and the final properties of the foam. A more fundamental look towards key parameters such as compatibility of the ternary (polyol/water/isocyanate) system, reactivity and viscosity, build-up of the reactive mixture, as well as polymer structure-foam properties relation characterized by means of DSC, DMS and FTIR will be presented.