Allyl bromide → Isoprene butadiene

Temperature

20 °C

In this experiment, an isoprene-butadiene copolymer rubber was prepared using an alcohol modified neodymium catalyst system. In this procedure, a one gallon (3.78 liter) reactor was charged with 1,214 grams of hexane containing 81.3 grams of butadiene and 558.43 grams of 1.23 molar diisobutylaluminum hydride (DIBAH) in hexane, (i.e., 25% weight percent DIBAH). The reactor was maintained at 20° C. by cooling. N-butanol (11.16 grams) was added with stirring. After stirring for thirty minutes, 107.5 grams of 10.1% neodymium solution (neodymium neodecanoate) diluted with 160 grams of dry hexane, was charged to the reactor. The-solution was stirred for another thirty minutes after which time 18.2 grams of allyl bromide was added. The cooling was stopped and the solution was allowed to warm up. A delayed exothermic reaction was noted. After twenty minutes, bring the solution temperatures to about 10° C. above ambient temperature. When the temperature ultimately dropped, the catalyst solution was aged by heating at 65° C. for ninety minutes. The catalyst prepared had a butanol-DIBAH!Nd-allyl bromide-butadiene molar ratio of 2-13!-1-2-20, respectively, and a concentration of 0.025 molarity with respect to the neodymium.

1. temperatureby cooling
2. stirringAfter stirring for thirty minutes
3. additionwas charged to the reactor
4. additionwas added
5. temperatureto warm up
6. customA delayed exothermic reaction
7. waitAfter twenty minutes
8. customto about 10° C.
9. customabove ambient temperature
10. additionWhen the temperature ultimately dropped
11. temperatureby heating at 65° C. for ninety minutes
12. customThe catalyst prepared

ORD record

ord-1e777457e722465d916ebae5c8c03946

Source dataset

uspto-grants-1996_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05502126