Polyurethane foams formulations

The urethane forming ingredients in a polyurethane foam formulation are the isocyanate (1) and the polyol (2) as shown in equation 3. 

A second new dispensable rigid polyurethane foam formulation was acquired that did not contain the phosphate adducts. Critical design requirements were the same as In the first formulation. The respec-... 

Two different dispensable rigid polyurethane foam formulations were found inadequate... 

BARK-DIISOCYANATE - POLYURETHANE FOAM FORMULATIONS USED FOR INFRA-RED (IR) AND FOR THERMOGRAVIMETRIC ANALYSIS (TGA)... 

Buszard, D.L. and Dellar, A.J., "The Performance of Flame Retardants in Rigid Polyurethane Foam Formulations," in Fire and Cellular Polymers, Eds., Buist, J.M., Grayson, J.J., and Wooley, W.D., Elsevier Applied Science Publishers, New York (1986). 

Kendrick T.C., Kingston B.M., Lloyd N.C., and Owen M.J., "Surface Chemistry of Polyurethane Foam Formulation, Part I", Journal of Colloid and Interface Science, Volume 24, pg. 135, 1967 ... 

The above cited diol, when incorporated into a flexible polyurethane foam formulation at a 5.6% level (10 phr based on the polyol) produced a self-extinguishing urethane foam, based on the Motor Vehicles Safety Standard 302 Flammability Test. 

SPI, soy fibre, and corn starch together with 0 0 per cent polyetho- polyol were also incorporated into a flexible polyurethane foam formulation. Stress-strain curves of the control foam and foams containing 10-20 per cent biomass material exhibited a considerable plateau stress region, but not for foams extended with 30—40 per cent of them. An increase in the hiomass content produced an increase in the foam density, whereas an increase in the initial water content produced the opposite effect. Foams extended with 30 per cent SPI, as well as those extended with 30 per cent soy fibre, displayed considerably higher resilience values than all other extended foams. The comfort factor increased by increasing the biomass content, and foams containing 10—40 per cent biomass showed significantly lower values in compression-set than the control foam [86]. 

Surfactants are added to a thermoset resin system to promote the dispersion of fillers in the resin matrix. Recently, surfactants have been used to disperse carbon nanotubes in polymer matrices [48-50]. Surfactants are of two types neutral and ionic. Surfactants have many applications in coating industries for the development of a water-based resin system [51]. Surfactants are added to phenolic or polyurethane foam formulation in which they facilitate formation of small bubbles. The size and uniformity of bubble formation results in a fine cell structure. A surfactant reduces the surface tension of resin formulations and provides an interface between the highly polar resin and the non-polar blowing agent. The surfactant for a particular resin system must be selected carefully so that it is compatible with the resin and resistant... 

TDA-derived polyols are made by alkoxylation. Polypropylene oxide adducts of I DA (14) and TDA-initiated polyether polyols (13,15) are used in rigid polyurethane foams and continue to be included in new formulations (62) as well as older appHcations. 

Flame retardants (qv) are incorporated into the formulations in amounts necessary to satisfy existing requirements. Reactive-type diols, such as A/ A/-bis(2-hydroxyethyl)aminomethylphosphonate (Fyrol 6), are preferred, but nonreactive phosphates (Fyrol CEF, Fyrol PCF) are also used. Often, the necessary results are achieved using mineral fillers, such as alumina trihydrate or melamine. Melamine melts away from the flame and forms both a nonflammable gaseous environment and a molten barrier that helps to isolate the combustible polyurethane foam from the flame. Alumina trihydrate releases water of hydration to cool the flame, forming a noncombustible inorganic protective char at the flame front. Flame-resistant upholstery fabric or liners are also used (27). 

The polyurethane industry is dominated by the multinational isocyanate producers. Several of the principal isocyanate producers, including BASF, Bayer, Dow, ICI, and Olin, also manufacture polyols, the other significant building block for polyurethanes. Annual production capacities of the global aromatic isocyanate producers are Hsted in Table 11. Polyols, mainly used for flexible foam production, account for 65 wt % in a flexible foam formulation, 35% in rigid polyurethane foams, and even less in PUIR foams. 

The one-shot polyethers now form the bulk of the flexible polyurethane foam now being manufactured. This is a result of the favourable economics of polyethers, particularly when reacted in a one-shot process, and because the polyethers generally produce foams of better cushioning characteristics. A typical formulation for producing a one-shot polyether foam will comprise... 

After 8 h of reaction, the reactor was allowed to cool. A two-layer liquid formed. The top layer was found to contain mostly polypropylene ether triols with about 20% by weight diethylene glycol and 5% by weight toluene diamines. The top layer was purified by vacuum distillation at 2 mm Hg and 200° C to produce 320 g of a light brown liquid residue. This residue (polyols) was used as a replacement for 5% by weight of the Pluracol 535 polyol in the formulation of a flexible polyurethane foam. A flexible foam which had good resiliency and a density of 2.2 Ib/ft3 was obtained. At higher replacement levels, lesser quality foams were obtained. 

Polyurethane elastomeric fibers, 205 Polyurethane elastomers, 201 Polyurethane foams, 20, 29, 202 preparation of, 251-252 Polyurethane formulations, one- and two-component system, 238-241... 

Flame retardants in polyurethane foams were determined by SFE-SFC [117]. Off-line SFE-SFC-FID was used for the analysis of additives in polyurethanes [52], and on-line SFE-SFC for extraction of additives from isocyanate formulations [107]. 

Surfactants used as lubricants are added to polymer resins to improve the flow characteristics of the plastic during processing they also stabilise the cells of polyurethane foams during the foaming process. Surfactants are either nonionic (e.g. fatty amides and alcohols), cationic, anionic (dominating class e.g. alkylbenzene sulfonates), zwitterionic, hetero-element or polymeric (e.g. EO-PO block copolymers). Fluorinated anionic surfactants or super surfactants enable a variety of surfaces normally regarded as difficult to wet. These include PE and PP any product required to wet the surface of these polymers will benefit from inclusion of fluorosurfactants. Surfactants are frequently multicomponent formulations, based on petro- or oleochemicals. 

Experimental Materials. All the data to be presented for these illustrations was obtained from a series of polyurethane foam samples. It is not relevant for this presentation to go into too much detail regarding the exact nature of the samples. It is merely sufficient to state they were from six different formulations, prepared and physically tested for us at an industrial laboratory. After which, our laboratory compiled extensive morphological datu on these materials. The major variable in the composition of this series of foam saaqples is the aaK>unt of water added to the stoichiometric mixture. The reaction of the isocyanate with water is critical in determining the final physical properties of the bulk sample) properties that correlate with the characteristic cellular morphology. The concentration of the tin catalyst was an additional variable in the formulation, the effect of which was to influence the polymerization reaction rate. Representative data from portions of this study will illustrate our experiences of incorporating a computer with the operation of the optical microscope. 

Industrially, silicone surfactants are used in a variety of processes including foam, textile, concrete and thermoplastic production, and applications include use as foam stabilisers, defoamers, emulsifiers, dispersants, wetters, adhesives, lubricants and release agents [1]. The ability of silicone surfactants to also function in organic media creates a unique niche for their use, such as in polyurethane foam manufacture and as additives to paints and oil-based formulations, whilst the ability to lower surface tension in aqueous solutions provides useful superwetting properties. The low biological risk associated with these compounds has also led to their use in cosmetics and personal care products [2]. 

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