Réaction #45001

Équation de réaction

1,3-butadiene

nBuLi

1,1-diphenylethylene

1,1-diphenylethylene

SnCl4

styrene

SnCl4

N2

→

1,3-butadiene styrene

Solvants

hexane

hexane

hexane

Conditions de réaction

Traitement

1. 1
   workup.ADDITIONTo a 1-gallon stainless steel reactor under a N2 blanket was charged 3.0 lbs
2. 2
   SéchageAll solvents were dried to less than 5 ppm water and oxygen free
3. 3
   Autreto proceed for 5 and ⅓ hours at 123-127° F
4. 4
   Autrelive cement was terminated with isopropanol
5. 5
   workup.ADDITIONwere added to the reactor
6. 6
   Autreto react for 2.75 hours at 125° F. and a further 16 hours at ˜70° F
7. 7
   Autrepurged
8. 8
   workup.ADDITIONwere added
9. 9
   Autreto terminated
10. 10
    Autreby evaporating the hexane in a rotoevaporator
11. 11
    Autrefinishing in a vacuum oven at 50° C
12. 12
    AutreMolecular weight analysis results by Gel Permeation Chromatography (GPC)

Mode opératoire

To a 1-gallon stainless steel reactor under a N2 blanket was charged 3.0 lbs. of 21.5% 1,3-butadiene in technical grade hexane, 3.0 lbs. of technical grade hexane and 67 g of 33% styrene in hexane. All solvents were dried to less than 5 ppm water and oxygen free. 64.7 mmol of nBuLi was charged to the reactor and polymerization was allowed to proceed for 5 and ⅓ hours at 123-127° F. 308 grams of a control sample was taken and live cement was terminated with isopropanol. A second 308 gram sample was also taken. It was calculated that a maximum of 51.3 mmol of carbon-bound lithium was still present in the reactor, 50.4 mmol of 1,1-diphenylethylene and 16 mmol of the vinyl modifier 2,2-di(tetrahydrofuryl)propane were added to the reactor and allowed to react for 2.75 hours at 125° F. and a further 16 hours at ˜70° F. A sample was taken for analysis and it was determined that 23.6% of the 1,1-diphenylethylene remained unreacted. A 306 gram sample was taken in a N2 purged crown-capped bottle and 1.7 mmol SnCl4 were added to terminated and couple the polymer. (It was calculated that a maximum of 0.021 mmol carbon-bound lithium was present per gram of cement.) Both the control sample and the SnCl4 coupled sample were worked up by evaporating the hexane in a rotoevaporator and finishing in a vacuum oven at 50° C. Molecular weight analysis results by Gel Permeation Chromatography (GPC) are shown in Table 3.

Source