Aspects of the Synthesis of Poly(styrene-block-isobutylene-block-styrene) by TiCl4-Co-initiated Cationic Polymerization in Open Conditions

Macromol

Dmitry G. Yakhvarov¹  Giyjaz E. Bekmukhamedov¹  Evgeny A. Ovcharenko²  Maria A. Rezvova²  Tatiana V. Glushkova²  Ivan A. Berezianko³  Pavel A. Nikishau³  Miraslau I. Makarevich³  Sergei V. Kostjuk³ 

[1] Alexander Butlerov Institute of Chemistry, Kazan Federal University, 420008 Kazan, Russia;Research Institute for Complex Issues of Cardiovascular Diseases, 650002 Kemerovo, Russia;Research Institute for Physical Chemical Problems of the Belarusian State University, 220006 Minsk, Belarus;

关键词: cationic polymerization;    living polymerization;    isobutylene;    styrene;    polyisobutylene;    poly(styrene-block-isobutylene-block-styrene);   

DOI  :  10.3390/macromol1040017

来源: DOAJ

【 摘 要 】

The cationic polymerization of isobutylene and its block copolymerization with styrene using DiCumCl/TiCl₄/2,6-lutidine initiating system has been studied in open conditions. It was shown that a higher concentration of proton trap is required in open conditions as compared to the glove box technique in order to have good control over molecular weight and polydispersity. Polyisobutylenes with M_n ≤ 50,000 g mol⁻¹ and low polydispersity (Đ ≤ 1.2) were prepared at [Lu] = 12 mM. The synthesis of poly(styrene-block-isobutylene-block-styrene) triblock copolymer (SIBS) in open conditions required the addition of proton trap into two steps, half at the beginning of the reaction and the second half together with styrene. Following this protocol, a series of triblock copolymers with different length of central polyisobutylene block (from M_n = 20,000 g mol⁻¹ to 50,000 g mol⁻¹) and side polystyrene blocks (M_n = 4000 g mol⁻¹–9000 g mol⁻¹) with low polydispersity (Đ ≤ 1.25) were synthesized. High molecular SIBS (M_n > 50,000 g mol⁻¹) with low polydispersity (Đ < 1.3) containing longer polystyrene blocks (M_n > 6000 g mol⁻¹) demonstrated higher tensile strength (~13.5 MPa).

【 授权许可】

Unknown