Epoxy water-soluble

In situ" derivatization of water soluble epoxy-alcohol... 

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). 

Two-component waterborne urethane dispersions are similar to the one-component PUD s in that a polyurethane dispersion comprises one of the two components. The second component is usually a crosslinker from the following classes of materials (a) polyisocyanates, (b) aziridines, (c) polycarbodiimides, and (d) epoxies. Many of the crosslinkers are not inherently water-soluble or water-dispersible. Therefore, they must be modified with surface active agents themselves, so as to become emulsifiable in water. 

The ability to perform the AE reaetion under eatalytie eonditions via the addition of moleeular sieves has greatly enhaneed the synthetie utility of the reaetion. For water-soluble epoxy aleohols, the eatalytie eonditions are benefieial for both enantioseleetivity and isolated yield. In addition, epoxy aleohols that are suseeptible to ring opening via nueleophilie substitution at the C-3 position also greatly benefit from eatalytie eonditions, sinee the substitution reaetion is known to be promoted by Ti(IV) speeies. 

When a polymer film is exposed to a gas or vapour at one side and to vacuum or low pressure at the other, the mechanism generally accepted for the penetrant transport is an activated solution-diffusion model. The gas dissolved in the film surface diffuses through the film by a series of activated steps and evaporates at the lower pressure side. It is clear that both solubility and diffusivity are involved and that the polymer molecular and morphological features will affect the penetrant transport behaviour. Some of the chemical and morphological modification that have been observed for some epoxy-water systems to induce changes of the solubility and diffusivity will be briefly reviewed. 

D. R. McCoy, M. Cuscurida, and G. P. Speranza. Demulsification of bitumen emulsions using water soluble epoxy-containing polyethers. Patent CA 1225004,1987. 

Carbamazepine, because of its poor water solubility has slow oral absorption. It is metabolized in the liver to an active metabolite, (10-11 epoxy carbamazepine) by oxidation as well as by hydrolysis and conjugation to inactive forms. 

When the relation between D and M is established, we can easily convert G(D) obtained by dynamic LLS into a differential molecular weight distribution, such as fw(M). We have successfully applied the above methods to various kinds of polymeric and colloidal systems, such as for Kevlar [15, 23], fluoropolymers (Tefzel Teflon) [12,30-35,52], epoxy [53-55],polyethylene [56,57], water-soluble polymers [18,50-51,58,59], copolymers [60-62], thermoplastics [63-65] and colloids [66-72]. Three of those applications are illustrated below. 

The conversion of dextran with 1,2-epoxy-3-phenoxypropane, epoxyoctane or epoxydodecane may be exploited for the preparation of amphiphilic dextran derivatives. Polymeric surfactants prepared by hydrophobic modification of polysaccharides have been widely studied, starting with the pioneering work of Landoll [261]. Neutral water-soluble polymeric surfactants can be obtained by reaction of dextran with 1,2-epoxy-3-phenoxypropane in 1 M aqueous NaOH at ambient temperature (Fig. 35, [229,233]). The number n of hydrophobic groups per 100 Glcp units varies between 7 and 22 depending on the reaction conditions. 2-Hydroxy-3-phenoxy propyl dextran ethers (DexP) behave like classical associative polymers in aqueous solution. In dilute solution, the intrinsic viscosity decreases significantly whereas... 

Amino-terminated telechelic polybutadiene was prepared by LiAlH4 reduction of amidino end-group in polybutadiene, which was polymerised by a water-soluble initiator, 2,2 -azobis(amidinopropane)dihydrochloride. The structure was analysed by 1H- and 13C-NMR, but functionality of 2.0 was obtained by a titration method [70]. Synthesis of co-epoxy-functionalised polyisoprene was carried out by the reaction of 2-bromoethyloxirane with living polymer that was initiated with sec-butyl lithium. The functionality of the resulting polyisoprene was 1.04 by 1H-NMR and 1.00 by thin layer chromatography detected with flame ionisation detection [71]. 

Due to their low dehydration temperatures and water solubilities, boric acid and sodium borates (borax pentahydrate and borax decahydrate) are mostly used as fire retardants in wood/cellulosic products such as timbers, plywood, particle board, wood fiber, paper products, and cotton products. In recent years, boric acid has also been used as fire retardant in epoxy intumescent coating, pheno-lics, urethane foam, and so on. When necessary, boric acid can be coated with silicone oil such as silicone to alleviate its water solubility in water-based coating. 

The synthesis of polymers containing diaza-crown ether groups in the main chain, i.e., poly(diaza-crown ether)s, has been recently achieved by incorporating these groups into macromolecular structures of conventional type, such as epoxy polymers 48,49,50) p0iyethers, and polyamides51>. In the former case, water soluble polymers could be obtained. 

Water is sometimes used as a solvent for water-soluble resins. Certain epoxy adhesives are available as water-based emulsion or latex formulations. In the early 1970s, during the time of the petroleum crisis, water-based adhesives were thought of as a possible replacement for solvent-based adhesives systems. However, water-based adhesives never met the lofty expectations primarily because of the time and energy required to remove water from the bond line, the corrosion that the water causes in drying ovens, and the poor moisture resistance of cured water-based adhesives. 

The resins based on glycerol and pentaerythritol are water-soluble and have low viscosity. They can have greater functionality and reactivity than conventional DGEBA resins. Resins based on polytaerythritol are claimed to have excellent adhesive properties including the ability to adhere to wet surfaces. They cure between 2 and 8 times faster than DGEBA epoxy resins and reduce the viscosity of DGEBA by 50 percent when used in concentration of 20 pph. 

Water is also sometimes used as a solvent for water-soluble resins. In the case of epoxy resins, water is generally used to disperse epoxy particles in an emulsion. These waterborne epoxy adhesives are discussed in Chaps. 4 and 14. 

Water-soluble products (e.g., 3- and 4-carbon epoxy alcohols) present obvious isolation problems which have been only partly solved. The other troublesome class of products Includes those epoxy alcohols which are unstable under the epoxidatlon and/or isolation conditions. This latter class consists of the three main types shown below ... 

The principle of miniemulsion polymerization to polyadditions of epoxyresins was successfully transferred to mixtures of different epoxides with varying diamines, dithiols, or diols which were heated to 60°C to form the respective polymers [125]. The requirement for the formulation of miniemulsions is that both components of the polyaddition reaction show a relatively low water solubility, at least one of them even below 10 5 g l1. The diepoxide bisphenol-A-diglycidylether was successfully used as epoxy component. In order to vary the obtained polymeric structure, tri- and tetra-functionalized epoxides were also used. As amino components a NH2 terminated poly(propylene oxide) with Mw=2032 g mol1, 4,4 -diaminobibenzyl, 1,12-diaminododecane, and 4,4 -di-aminodicyclohexylmethane were applied. As other addition components beside amine, 1,6-hexanedithiol and Bisphenol A were used. The hydrophobic compo-... 

Hercules Kymene 557 is the cationic, water-soluble, wet strength resin, which conservators know because of its use in the manufacture of calcium carbonate filled P/D paper. In its synthesis, a condensation polymer of adipic acid and diethylene triamine is reacted with epichloro-hydrin to introduce reactive epoxy groups. The behavior of Kymene in dispersed fiber has been investigated by Bates (6,7). 

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