Lewis bases are frequently employed as polar modifiers to enhance the 1

2-selectivity of butadiene anionic polymerization. In this work

we report four novel N

O-bidentate Lewis bases bearing different alkyl substituents: 1-(2-methoxyethyl)piperidine (MOD 1)

1-(2-ethoxyethyl)piperidine (MOD 2)

1-(2-propoxyethyl)piperidine (MOD 3)

and 1-(2-butoxyethyl)piperidine (MOD 4). A comparative study was conducted between these newly synthesized polar modifiers and five commonly used

previously reported modifiers

focusing on their effects on the anionic polymerization of butadiene. Additionally

we investigated how the dosage of various modifiers and the polymerization temperature influence the polymerization behavior. The results show that the newly designed N

O-bidentate polar modifiers can achieve a high degree of 1

2-structural regulation in polybutadiene at relatively low dosage levels. Their regulatory effectiveness remains stable across different polymerization temperatures

demonstrating both high efficiency and excellent stability.