Butanol reaction + diisocyanate

Burkus and Eckert (14) have studied the kinetics of the triethylamine catalyzed reaction of 2,6-tolylene diisocyanate with 1-butanol in toluene... 

The ratio of the rate constants for the reaction of p-menthane diisocyanate with 1- and with 2-butanol at 25° was 3.5 with copper naphthenate as the catalyst but rose to 26 with lead naphthenate. By following the reaction to high conversion with 1-butanol, the ratio of the reactivities of the two isocyanate groups was found to depend on the catalyst used as shown by the values... 

In the absence of catalysts the reactivity follows the order urea > water > butanol. In the presence of catalysts the order of reactivity is reversed and the alcohol exhibits the highest reactivity. It is interesting to note that the preferential acceleration of the alcohol reaction by diaza-bicyelooctane is more pronounced than that by iV-methylmorpholine or triethylamine. The high ratios of relative rates for the alcohol and water reactions observed with certain catalysts make these useful in the so-called one-shot foaming process in which for good foam stability a rapid polymerization process involving a reaction between diisocyanate and bifunctional hydroxy compounds and a slower CO2 evolution are desirable. 

Effect of Hydrolyzable Chlorine on Activity of Tin Catalysts. The effect of small amounts of hydrolyzable chlorine on the catalytic activity of DBTDL was studied on the model aliphatic system—isocy-anatoethyl methacrylate and n-butanol. The presence of the hydrolyzable chlorine in isocyanate usually decreases the reactivity of isocyanates in the urethane reaction. The results of measurements of the chlorine effect on the change of the rate constant is summarized in Figure 8. It was determined that the very small amounts of the hydrolyzable chlorine, especially in the form of carbamoyl chloride, increased at the beginning the rate constant for the urethane reaction catalyzed by DBTDL and after achieving the maximum at 500 ppm of chlorine the reactivity decreased. This effect was not observed when benzoyl chloride was used in place of carbamoyl chloride. It was assumed that the activation effect of the chlorine was due to the interaction of the carbamoyl chloride with the DBTDL catalyst. In order to understand this effect, the interaction of DBTDL with carbamoyl chloride of hexamethylene diisocyanate (with and without the presence of n-butanol) was studied using the IR technique. Results are summarized in Figure 9. 

The chemo-enzymatic synthesis of polyurethanes has been reported through the inter-esterification of castor oil and linseed oil at ambient temperature, using lipase as a catalyst and foUowed by treatment of the inter-esterified product with TDI. In the first step, partial esters are prepared by transesterification of soybean and linseed oils with n-butanol in the presence of lipozyme (a lipase) as the catalyst. The partial esters are then reacted with different diisocyanates to obtain a series of polyurethanes. The reaction of polyhydroxy compounds (transesterification reaction between different compositions of castor oil and glycolysed poly(ethylene terephthalate)) with diisocyanates offers a polyurethane network for new insulating coating applications. ... 

The relative reactivity of 1-butanol with lEM and other commercial isocyanates was studied by Frisch, Kresta and Wongkamolsech (2). As seen in Table 2, lEM reacts at a rate that is almost twice as fast as hexamethylene diisocyanate under these conditions. The presence of a low level (200-400 ppm) hydrolyzable chloride impurity in the lEM appears to accelerate this reaction. 

Addition copolymers containing IBM retain much of this reactivity with primary alcohols. As seen in Table 3, the reaction rate constant of 1-butanol with polymerized IBM is about half that of monomeric IBM under the same conditions (3). Thus the reactivity of IBM-containing polymers is similar to that of other primary aliphatic isocyanates such as hexamethylene diisocyanate. This very good retention of NCO reactivity allows the use of IBM to incorporate NCO functionality into a variety of vinyl copolymers. In general, IBM-containing copolymers retain >90% of the theoretical isocyanate functionality. 

In a second series of investigations [44-46], Caraculacu et al., studied the reactivity of the functional groups 4,4 -DBDI. The rate constants of the reactions of diisocyanates with n-butanol were determined by using the IR spectophotometric method of Bailey [99]. The rate constants of the consecutive reactions were determined by the time ratio method developed by Frost and Pearson [100]. 

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