Polyester resins water-extended polyesters

Aropol WEP, Water-extended polyester resin, Ashland Chemical Co., Composite Polymers Div. 

Dicylopentadiene Resins. Dicyclopentadiene (DCPD) can be used as a reactive component in polyester resins in two distinct reactions with maleic anhydride (7). The addition reaction of maleic anhydride in the presence of an equivalent of water produces a dicyclopentadiene acid maleate that can condense with ethylene or diethylene glycol to form low molecular weight, highly reactive resins. These resins, introduced commercially in 1980, have largely displaced OfXv o-phthahc resins in marine apphcations because of beneficial shrinkage properties that reduce surface profile. The inherent low viscosity of these polymers also allows for the use of high levels of fillers, such as alumina tfihydrate, to extend the resin-enhancing, fiame-retardant properties for apphcation in bathtub products (Table 4). 

The applications of the unsaturated polyester resins were increased in the late 1960s by the introduction of water-extended polyesters. In these materials water is dispersed into the resin in very tiny droplets (ca 2-5 p.m diameter). Up to 90% of the system can consist of water but more commonly about equal parts of resin and water are used. The water component has two basic virtues in this system it is very cheap and because of its high specific heat it is a good heat sink for moderating cure exotherms and also giving good heat shielding properties of interest in ablation studies. 

Extenders. Materials used in chernical formulations to add bulk or volume and reduce cost.. Extenders range from materials like sawdust, glass fibers, and oils used to add bulk to phenolic resins to water held in a matnx, extending polyester resins. 

EXTENDER. A low-graxily material used in paint, ink. plastic, and rubber formulations chiefly to reduce cost per unit volume by increasing bulk, Extenders include dialomaccou.s earth, wood flock, mineral rubber, liquid asphalt, etc. Microscopic droplets of water fixed permanently in a plastic matrix are an efficient extender tor polyester resins. In the food industry, the term refers to certain extruded proteins, especially those derived from soybeans, which are used in meat products to provide equivalent nutrient values at lower cost. Made from defatted soy flour, they are often called textured proteins. 

Chem. Descrip. Calcium carbonate CAS 471-34-1 EINECS/ELINCS 207-439-9 Uses Filler/extender used in interior flat paint and exterior house paints, rubber compds. (NR, SR), polyvinyl plastisols, PE and polyester resins, putty and caulk, ceramics, adhesives, linoleum, floor tile, aril textile coatings filler in heels, soles, flooring, mats, molded and extruded goods, foam prods., footwear, sundries, SMC Properties Wh. powd. 7.0 avg. particle diam. 99.5% finer than 44 50.0% finer than 7 0.03% sol. in water sp.gr. 2.70-2.71 dens. 22.57 Ib/gal solid bulk dens. 58 Ib/ff (loose) oil absorp. 13 cc/100 g brightness (Hunter) 93 ref. index 1.6 pH 9.5 (sat.) hardness (Mohs) 3.0 Toxicology Nontoxic Camel-FINE [IMERYS]... 

Microcellular polyurethanes for shoe soling are of both the polyester and polyether types. Polyester types were developed first and owing to their generally superior mechanical properties they tend to be used in the thinner sole, high quality section of the market. Such polyester systems are usually based on quasi-prepolymers (made from part of the polyester and the MDI) and a resin blend made up of the rest of the polyester, the chain extender (usually butane diol), catalysts, surfactants and water to produce carbon dioxide to blow the foams. The use of a quasi-prepolymer enables the two... 

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