Polyurethane foam manufacture

More than 50% of the rigid polyurethane foams manufactured in the United States in 1994 are used in the constmction industry (Table 10). About... 

Other Octoate Uses. Metal octoates are also used as driers in printing inks. Another appHcation of octoates includes the use of the aluminum salt to gel paint. Stannous, dibutyltin, and bismuth carboxylates find appHcation as catalysts in polyurethane foam appHcations in order to obtain a reaction efficiency suitable for industrial production. In polyurethane foam manufacture the relative rate of polymeriza tion and gas foaming reactions must be controlled so that the setting of the polymer coincides with the maximum expansion of the foam. 

The unique surface characteristics of polysiloxanes mean that they are extensively used as surfactants. Silicone surfactants have been thoroughly studied and described in numerous articles. For an extensive, in-depth discussion of this subject, a recent chapter by Hill,476 and his introductory chapter in the monograph he later edited,477 are excellent references. In the latter monograph, many aspects of silicone surfactants are described in 12 chapters. In the introduction, Hill discusses the chemistry of silicone surfactants, surface activity, aggregation behavior of silicone surfactants in various media, and their key applications in polyurethane foam manufacture, in textile and fiber industry, in personal care, and in paint and coating industries. All this information (with 200 cited references) provides a broad background for the discussion of more specific issues covered in other chapters. Thus, surfactants based on silicone polyether co-polymers are surveyed.478 Novel siloxane surfactant structures,479 surface activity and aggregation phenomena,480 silicone surfactants application in the formation of polyurethane foam,481 foam control and... 

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]. 

Antiblaze 19, a phosphonate ester and flame retardant used in textiles and polyurethane foam manufactured from trimethyl phosphite, dimethyl methylphosphonate, and trimethyl phosphate. 

Hagmar L, Stromberg U, Welinder H, et al. 1993. Incidence of cancer and exposure to toluene diisocyanate and methylene diphenyldiisocyanate a cohort based case-referent study in the polyurethane foam manufacturing industry. Br J Ind Med 50(11) 1003-1007. 

Kazuyuki 0, Higashi T, Nakadate T, et al. 1992. Fom year follow-up of effects toluene diisocyanate exposure on the respiratory system in polyurethane foam manufacturing worker. Int Arch Occup Environ Health 63 565-569. 

Hagmar, L., Welinder, H. Mikoczy, Z. (1993a) Cancer incidence and mortality in the Swedish polyurethane foam manufacturing industry. Br. J. ind. Med., 50, 537-543... 

Omae, K., Nakadate, T., Higashi, T., Nakaza, M., Aizawa, Y. Sakurai, H. (1992a) Four-year follow-up of effects of toluene diisocyanate exposure on the respiratoiy system in polyurethane foam manufacturing workers I. Study design and results of the first cross-sectional observation. Int. Arch, occup. environ. Health, 63, 559-564... 

This reaction is catalyzed by a platinum catalyst such as Speier s catalyst, chloroplatinic acid. Because the catalyst also isomerizes the terminal double bond, the reaction maybe run with an excess of vinyl to make sure all the reactive sites on the silicone are reacted. SiH also reacts with ROH and, for this reason, alkoxy end-capped polyethers maybe preferred. Alkoxy end-capped polyethers are also useful when the surfactant will be used in a chemically reactive system such as polyurethane foam manufacture. 

More than 50% of the rigid polyurethane foams manufactured in the United States in 1994 are used in the construction industry (Table 10). About 60% of the total rigid foam is used in laminated boards and insulation panels about 30% is poured in place. Insulated appliances is another important use of rigid insulation foam. 

A commercially important category of polyether-modified PDMS is used in polyurethane foam manufacture. Used at a concentration of about 1%, these PDMS derivatives are essential to ensure a uniform distribution of foam properties over the cross section of the foam slab. 

The detailed descriptive information in this paper-covered book is based on U.S. patents since 1965 relating to polyurethane foam manufacture. A few very relevant earlier patents are also included. The book supplies detailed technical information and can be used as a guide to the U.S. patent literature in this field. The Table of Contents is organized in such a way that it can serve as a subject index. 

Tphe surface activity of block copolymers containing dimethylsiloxane units as one component has received considerable attention. Silicone-poly ether block copolymers (1,2,3) have found commercial application, especially as surfactants in polyurethane foam manufacture. Silicone-polycarbonate (4, 5), -polystyrene (6, 7), -polyamide (8), -polymethyl methacrylate (9), and -polyphenylene ether (10) block copolymers all have surface-modifying effects, especially as additives in other polymeric systems. The behavior of several dimethylsiloxane-bisphenol A carbonate block copolymers spread at the air—water interface was described in a previous report from this laboratory (11). Noll et al. (12) have described the characteristics of spread films of some polyether—siloxane block co-... 

W. S. Toluene diisocyanate—engineering and medical control of exposures in polyurethane foam manufacturing. Am Ind Hyg Assoc g, 1957, 18, 331-34. 

Gandevia, G. Studies ov ventilatory capacity and histamine response during exposure to isocyanate vapour in polyurethane foam manufacture. Br J Ind Med 20 204-09, 1963. 

Water is considered, in polyurethane foam manufacture, as a chemical blowing agent, because the gas generation is a consequence of a chemical reaction. 

B) For polyurethane foam manufacturers with 20 to 99 employees, within 255 days after the effective date of this section. 

As foam control agents in polyurethane foam manufacture (primary usage of these surfactants)... 

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