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Published August 10, 2014 | public
Journal Article

Ruthenium catalyzed synthesis of functionalized polypentenamers

Abstract

Polypentenamers and their functionalized derivs. are synthesized by equil. ring-opening metathesis polymn. (ROMP) using well- defined ruthenium catalyst systems. The unique feature of the equil. polymn. opens a way for the synthesis of durable, environmentally friendly and recyclable materials. The ruthenium catalyzed polymn. and co- polymn. of cyclopentene (2.17 M) at low catalyst loading (0.01 %) in toluene soln. were investigated. The monomer- polymer equil. concn. (45 - 55 %) was achieved within one hour at room temp. (MW: 129 kDa; PDI: 1.64). The mol. wt. of the polypentenamers gradually decreased as the reaction time was prolonged up to 16h (MW: 76kDa) meanwhile the PDI values gradually increased (up to 1.84) and the isolated polymer yields remained comparable. The co- polymn. of cyclopentene with 0.5 % 2, 5- norbornadiene at 0 °C in toluene results in the formation of cross- linked polypentenamers. The gradual addn. of dild. 2, 5- norbornadiene soln. over the cyclopentene equil. ROMP resulted in significant polymer mol. wt. increase (MW: 3220 kDa; PDI: 1.5) and shorter gelation time comparing to the polymers obtained in the absence of 2, 5- norbornadiene at the same condition (MW: 408 kDa; PDI : 1.32). Highly polar polyhydroxy polypentenamers (MW: 16.6 kDa; PDI: 1.5) have been synthesized by equil. ROMP of 3- cyclopentene- 1- ol or acyclic diene metathesis polymn. (ADMET) of 1, 6- heptadien- 4- ol in THF. The thermodn. of 3- cyclopentene- 1- ol ROMP was investigated. Equil. of growing chain and monomer was obsd. and the thermodn. parameters were detd. as: ΔH = - 6.4 kcal • mol^(-1); ΔS = - 21.4 cal • mol^(-1)• K^(-1). The co- polymn. of 1, 6- heptadien- 4- ol with cyclopentene (1 : 1) resulted in a polymer contg. block-polymer (65 %) and alternating polymer (35 %) units, resp. The synthesis of cross- linked polypentenamers, polyhydroxy polypentenamers and the thermodn. investigation of their equil. polymn. are reported. Synthesis of polyhydroxy polypentenamers with ruthenium catalyzed acyclic diene metathesis polymn. (ADMET) and equilibrium ring opening metathesis polymn. (ROMP).

Additional Information

© 2014 American Chemical Society.

Additional details

Created:
August 20, 2023
Modified:
October 20, 2023