Unsaturated polyester oligomer synthesis

Synthesis of Unsaturated Polyester A. The unsaturated polyester oligomer A was prepared in a 500 milliliter 4-neck flask fitted with a variable speed stirrer, a heating mantle, a gas inlet tube, a thermometer, a Dean-Starke trap and a condenser. The flask was charged with 147.0 g (1.5 mol) of maleic anhydride (Amoco), 195 g (1.88 mol) of 1,5-pentane diol (BASF), about 35 ml of xylene and 0.3 g of Fascat 4100. Then heated slowly under a nitrogen blanket to 175° C while the water of condensation was removed... 

Although low-molar-mass aliphatic polyesters and unsaturated polyesters can be synthesized without added catalyst (see Sections 2.4.1.1.1 and 2.4.2.1), the presence of a catalyst is generally required for the preparation of high-molar-mass polyesters. Strong acids are very efficient polyesterification catalysts but also catalyze a number of side reactions at elevated temperature (>160°C), leading to polymers of inferior quality. Acid catalysts are, therefore, not much used. An exception is the bulk synthesis of hyperbranched polyesters reported in Section 2.4.5.1, which is carried out at moderate temperature (140°C) under vacuum in the presence of p-toluene sulfonic acid catalyst. The use of strongly acidic oil-soluble catalysts has also been reported for the low-temperature synthesis of polyester oligomers in water-in-oil emulsions.216... 

The Effect of Amine Structure In order to evaluate the effects of eunine functionality and substitution on the crosslinking reaction/ several amine terminated urethane oligomers were synthesized by the same procedure as used in the synthesis of the LPUR. The oligomers were prepared in Urethane Grade MEX. These amines were evaluated with the allyl terminated unsaturated polyester as the unsaturation source. The composition and the properties of the oligomers are shown in Table IV. 

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