Method for preparing polybutene by using catalyst containing N-propanol
Disclosed a method for preparing polybutene by using a catalyst including normal propanol, wherein the polybutene has 40 to 70% of vinylidene content and 10% or more of tetra-substituted double bond content by using a complex catalyst including normal propanol as a cocatalyst and a main catalyst such as boron trifluoride. The method comprises: introducing, to a raw reaction material including 10 wt % or more of isobutene, a complex catalyst including normal propanol as a cocatalyst and boron trifluoride as a main catalyst; and polymerizing the raw reaction material at a reaction temperature of −33 to 33° C. under a reaction pressure of 3 to 50 kg/cm 2 , wherein the vinylidene content is adjusted by adjusting the reaction temperature.
1. A method for preparing polybutene having 40 to 70% of vinylidene content and 10% or more of tetra-substituted double bond content, the method comprising:
introducing, to a raw reaction material including 10 wt % or more of isobutene, a complex catalyst, including normal propanol as a cocatalyst and boron trifluoride as a main catalyst in a molar ratio of normal propanol/boron trifluoride of 1 to 1.5; and
polymerizing the raw reaction material at a reaction temperature of −33 to 33° C. under a reaction pressure of 3 to 50 kg/cm 2 , wherein the vinylidene content is adjusted by adjusting the reaction temperature;
wherein the vinylidene content is adjusted by adjusting the reaction temperature according to Formula 1:
1.2 ×|T|≤ΔV ≤3 ×|T| [Formula 1]
wherein,
T represents the reaction temperature; |T| represents variation of the reaction temperature based on a reaction temperature of 0° C.; and ΔV represents variation of the vinylidene content.
2. The method for preparing polybutene of claim 1 , wherein the boron trifluoride is 0.02 to 1 parts by weight with respect to 100 parts by weight of isobutene.
3. The method for preparing polybutene of claim 1 , wherein the polymerization is carried out for 5 to 100 minutes.
4. The method for preparing polybutene of claim 1 , wherein for adjusting terminal vinylidene, the isobutene conversion rate is 80% or more.
5. The method for preparing polybutene of claim 1 , wherein a number average molecular weight of polybutene is 300 to 5,000.