Polyurethane water-based

Some commercial durable antistatic finishes have been Hsted in Table 3 (98). Early patents suggest that amino resins (qv) can impart both antisHp and antistatic properties to nylon, acryUc, and polyester fabrics. CycHc polyurethanes, water-soluble amine salts cross-linked with styrene, and water-soluble amine salts of sulfonated polystyrene have been claimed to confer durable antistatic protection. Later patents included dibydroxyethyl sulfone [2580-77-0] hydroxyalkylated cellulose or starch, poly(vinyl alcohol) [9002-86-2] cross-linked with dimethylolethylene urea, chlorotria2ine derivatives, and epoxy-based products. Other patents claim the use of various acryUc polymers and copolymers. Essentially, durable antistats are polyelectrolytes, and the majority of usehil products involve variations of cross-linked polyamines containing polyethoxy segments (92,99—101). 

Interest in polyurethane ionomers has increased in the last decade because of their growing uses in water-based coating, adhesives, medical, and semiconductor applications. However, relatively little information has been published regarding the synthesis and... 

As with water-based latex paints, the substrate on which the solvent-based paint is applied will influence the emission rates of VOCs. Kwok et al. (2003) showed that emission rates of aromatic VOCs from a polyurethane lacquer in the first 10 hours were 65% greater when the substrate was aluminum rather than plywood. VOCs from the former were emitted in an evaporation process, while from the latter they emitted largely in a diffusion-controlled process. 

Hydrolysis temperature. The effect experienced particularly by polyester-based polyurethanes, where prolonged contact with water or water-based liquids causes breakdown and failure of the polyurethane. 

The addition of small amounts of fluorinated polyols to conventional aqueous polyurethane coatings can improve their water resistance and mechanical properties considerably 47 FEVE resins can be applied as water-based coatings and cured at 160°C (320°F) for 25 min to produce coatings with high gloss and good water and weather resistance.48 They may also be cured with water-based hardeners.49... 

Ye. P. Mamunya, V. I. Shtompel, E. V. Lebedev, P. Pissis, A. Kanapitsas, and G. Boiteux, Structure and water sorption of polyurethane nanocomposites based on organic and inorganic components, Eur. Polym. J. 40, 2323-2331 (2004). 

Latex-free gloves are often made of polyurethane, which cause fewer allergic reactions. These polyurethane materials can be used with oil- or water-based creams and ointments, and they deteriorate less in storage. 

Air sampling for occupational exposure to pesticides normally consists of measurement of pesticide concentrations in the worker s breathing zone, with a portable air-sampling pump and a sampling train which includes some type of collection device. The latter device, or sampling media, selected are based on the physical and chemical properties of the compound to be measured. Field workers may be exposed to chemical vapors, solid particulates or water-based aerosols. Examples of sampling media include membrane filters, sorbent tubes, polyurethane foam and charcoal. A discussion of pesticide exposure provides a useful review of methods for respiratory exposure measurement (Nigg etal, 1990). 

Aqueous polyurethane systems have been developed which are considered to be safe from a health and safety point of view. They do not contain harmful isocyanates. The major application of this type of system is for coatings and floor finishes. Aqueous systems are based on single-pack, clear-water-based polyurethane. Two-pack and pigmented systems are also available. 

Water-Base Mold Releases. Water-base release agents are being used more widely. Solvent-base agents evaporate too quickly in warm areas. One example is a hydro-alcoholic solution of saponified fatty acids claimed to produce a dry-fihn coating. Axel Plastics Research Laboratories in Woodside, NY has a new product. Mold Wiz H40-3U, for flexible polyurethane foam. This material is heated to evaporate the water and is then applied with high-pressure spray equipment (44). 

Mortrim [Morton], TM for a series of one and two-component solvent-based and water-based polyurethane adhesives. 

DispercoII. [Bayer Miles] Polychloro-butadiene and polyurethane latexes for formulation of water-based contact cements, laminating and mastic adhesives for the automotive, construction, furniture, footwear, and iricg. industries. 

Milloxane. [Polyurethane Spec.] Water-based, solvent-based and 100% solid polyurethanes. 

Since the 1970s a trend to use water-based coating systems and glues instead of solvent-based products has been apparent. Most water-based paints and lacquers use polyurethane or acrylate as binders. For technical reasons the systems still contain organic cosolvents as well as pigments, biocides and surfactants (Hansen et al., 1987). 

Polyurethane coatings are strong and durable. They can be found on surfaces that need to be flexible, abrasion resistant, and chemical resistant, such as dance floors and bowling alleys. Water-based coatings are often used on airplanes and other transportation equipment. Polyurethane powder coatings are also used on fluorescent lights, refrigerators, car wheels and trim, lawnmowers, patio furniture, and ornamental iron. 

Adhesive-coated expanded PS shapes have been used as an alternative to foam-inplace polyurethane systems (see Section 13.1.3). The shapes are deposited into a corrugated box, covered with a release film, the product added, another sheet of release film put in place, and the carton filled with the adhesive-coated shapes. When the water-based adhesive dries, a pair of resilient cushions surrounds the product. 

Non-insulating foam products typically utilize hydrocarbons, such as isobutane, pentane, isopentane, and hexane. The use of CO2 (either water-based or liquid) is a major identified option to reduce the emission of non-HCFC blowing agents from polyurethane foam and extruded polystyrene boardstock applications. However, the thermal insulation properties of C02-blown foam are significantly compromised when compared to halocarbon-blown foam. Halocarbons (i.e., HCFCs, HFCs) are thus expected to be used in insulation foam manufacture for several years into the future. The primary HCFC replacements in these sectors are expected to be the liquid HFCs, which may see extensive use once HCFCs can no longer be used. 

As previously noted, the primary use for this elastomer has been as solvent-based adhesives and sealants. Solvent-based products are losing market share to water-based poly-chloroprenes, to other polymer types such as acrylics and polyurethanes, and to hot melt adhesives. However, where the processing facility is able to contain the vapor emissions, a solvent-based adhesive or sealant is preferred because of better wetting of surfaces, faster drying, and higher performance of the cured or dried product. Many rubber bonding... 

Many interior fittings (e.g., instrument panel, door and sidewall panels, package trays, seat linings, boot carpetings, rear window shelves, etc.) are often manufactured by vacuum drawing and laminating the cover sheet material (leatherette, textile, leather, etc.) onto the trim panel. The use of hot-melt (also cross-linking) adhesives and water-based polyurethane adhesives (with hardener) is state of the art for this type of component production. 

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