Formaldehyde scavenger

Traces of formaldehyde, present in neat end-capped polymer or produced by processing polymer under abusive conditions, detract from polymer stabihty. Commercial resins typically contain formaldehyde scavengers. Nitrogen compounds, especially amines and amides, epoxies, and polyhydroxy compounds, are particularly efficacious scavengers. 

Substituted Hydantoins. 5-Methylhydantoin [616-03-5] has been selected from several stmctures as a formaldehyde scavenger for color photosensitive materials and water-thinned inks and coatings (102,103). 

Foam. PhenoHc resin foam is a cured system composed of open and closed ceUs with an overall density of 16—800 g/cm. Principal appHcations are in the areas of insulation and sponge-like floral foam. The resins are aqueous resoles cataly2ed by NaOH at a formaldehyde phenol ratio of ca 2 1. Free phenol and formaldehyde content should be low, although urea may be used as a formaldehyde scavenger. 

Formaldehyde Scavenging. The formation of oxazoHdines from alkanolamines and formaldehyde is rapid at room temperature and provides a method for the elimination of excess formaldehyde from products such as urea—formaldehyde resins. AEPD and TRIS AMINO are the products of choice for this purpose because one mole of each will react with two moles of formaldehyde (22). 

Bu4N F , ethylenediamine (ethylenediamine was used as a formaldehyde scavenger), 45-98% yield. 

The lower cost of the urea-modified PF resins is a combination of PF solids extension by lower cost urea and improved adhesion and distribution capabilities. The improvements in storage stability stem from the thinning and dilution effects as well as from the formaldehyde scavenging. Liquid PF resoles with high free formaldehyde contents tend to be less stable in storage. 

Triazinanones are cleaved by aqueous HCl at room temperature or at 50 °C at pH 3-5 if a scavenger for the formaldehyde released is added. In Knapp s synthesis of Tetrahydropseudodistomin, the milder conditions were used with diethanolamine serving as the formaldehyde scavenger [Scheme 8.164].362... 

Release of larger amounts of formaldehyde Formaldehyde-free or low formaldehyde finishes, selection of products and condensation conditions (better than formaldehyde scavengers and cheaper than washing with new drying)... 

The question of the contribution of UF resin hydrolysis to board emission is not a trivial one. If resin hydrolysis contributes significantly to emission, then, in principle, the board would retain the potential to emit during its useful life, in contrast to the situation if all the emission results from free formaldehyde. In the former case, efforts to minimize emission must be directed toward resin stabilization and/or to ensuring that incorporated formaldehyde scavengers retain their effectiveness at low formaldehyde activities for the board s entire useful life. Another consequence of continued resin hydrolysis is possible limits on the durability of UF bonded products in this case improvement may be expected from more stable resins. 

Affect the equilibrium concentration in an unventilated system, C. A coating containing a formaldehyde scavenger would act by binding formaldehyde, thus reducing the equilibrium concentration. On the other hand some surface finishes will introduce extra formaldehyde, and may thus increase C. ... 

AEPD AEPD 85 AI3-03358 Aminoethyl propanediol 2-Amino-2-ethylpropanediol 2-Amino-2-ethyl-1,3-propanediol EINECS 204-101-2 2-Ethyl-2-amino-propanediol NSC 8803 1,3-Propanediol, 2-amino-2-ethyl- AEPD -85 AEPD . Pigment dispersant, neutralizing amine, corrosion inhibitor, acid-salt catalyst, pH buffer, chemical and pharmxeutical intermediate and solubilizer. Chemical intermediate, formaldehyde scavenger, acid-salt catalyst for permanent-press resins, corrosion Inhibitor. Crystals mp = 37,5° bpto = 152-153° d = 1.0990 freely soluble In H2O soluble In alcohols pH 0.1,1M aqueous solution, Whittaker Clark Daniels. 

Other AR mediators, such as divalent ion chelators, formaldehyde scavenges, such as citraconic anhydride, metal ions, or proteolytic enzymes can enhance AR in certain cases however, their applications are not universal and, in some cases, may even inhibit immunostaining. As noted above, the removal of steric barriers that restrict access of the antibody to its target epitope is a key component of aR." In this context, heating may serve to promote the extraction of diffusible proteins out of the tissue sections following cross-link reversal or proteolytic treatment, opening physical holes or channels in the tissue sections that allow better penetration of antibodies. The physical process of opening holes or channels within the tissue section also likely explains the modest success of ultrasonics as an AR method. ... 

Thermal degradation of polyoxymethylene and polyacetals results in the formation of formaldehyde, which is furthermore catalyzed by oxidation of formaldehyde to formic acid. In addition to antioxidants and acid scavengers, formaldehyde scavengers are used in polyacetal formulations. Formaldehyde scavengers of choice are nitrogen compounds, for example, melamine derivatives such as benzoguanamine, urea derivatives such as allantoin, hydrazides, imides, and polyamide. 

Surfactants are used to control cell size and structure. The most common surfactants are siloxane-oxyalkylene copolymers, polyoxyethylene sorbitan fatty acid esters, and the condensation products of ethylene oxide with castor oil and alkyl phenols. A commonly added additive is urea which is used as a formaldehyde scavenger. Very fine particle size inorganic fillers can be added to act as nucleating sites and to promote finer, more uniform cell structure, as well as increased compressive strength, but at a cost of higher density. 

Various formaldehyde scavengers are known. Some common ones are urea, ammonia, melamine, " ammonium chloride, and acetoacetamide. A linear correlation exists between the added ammonia amount and the reduction of residual formaldehyde in a nticrocapsule slurry. Furthermore, ammonia can improve the microcapsules waU impermeability/durability and thermal resistance. A similar finding was also reported by using melamine as the formaldehyde scavenger. ... 

Greene, J. T. Formaldehyde scavenging process useful in manufacturing durable press finished fabric. US 5112652, 1992. 

MAJOR APPLICATION Thermal stabilizer for polyoxymethylene, and stabilizer for polyacetal resin. Because of high amide concentration, nylon 3 shows properties of an excellent formaldehyde scavenger. 

OTHER POLYMER SHOWING THIS SPECIAL PROPERTIES Formaldehyde scavenger copolyamide composed of Nylon 6, Nylon 6,6 and Nylon 6,10. 

Chem. Descrip. 2-Amlno-1-butanol CAS 96-20-8 EINECS/ELINCS 202-488-2 Uses Pigment dispersant neutralizing/emulsi ing amine corrosion inhibitor acid-salt catalyst pH buffer chemical and pharmaceutical intermediate solubilizer raw material in polymer synthesis formaldehyde scavenger in coalings, emulsions... 

Uses Emulsifier for creams/lotions, oils, fats, waxes, cosmetics, min. oil and paraffin wax emulsions, leather dressings, textile specialties, polishes, cleaners absorbent for acidic gases medicine buffer in cosmetics solubilizer, stabilizer, buffer in pharmaceuticals formaldehyde scavenger in curing U-F resins, phenolics amine soaps (metalworking fluids) synthesis of surfactants, vulcanization accelerators, pharmaceuticals chemical intermediate for paints, etc. 

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