TY - JOUR
T1 - Synthesis of high-vinyl isoprene and styrene triblock copolymers via anionic polymerization with difunctional t-BuLi initiator
AU - Lee, Pin Chen
AU - Wang, Cheng Chien
AU - Chen, Chuh Yung
N1 - Funding Information:
We gratefully acknowledge financial support from the Ministry of Science and Technology of the Republic of China (MOST 107-2823-8-006-007-, MOST 107-2221-E-006-002-, and MOST 107-2218-E-006-001-). We are also grateful to Ms. Bi-Yin. Lin ( National Cheng Kung University , 701 Tainan, Taiwan, R.O.C.) for her contribution to the 1 H NMR, 13 C NMR, and 2D HSQC experiments. Appendix A
Funding Information:
We gratefully acknowledge financial support from the Ministry of Science and Technology of the Republic of China (MOST 107-2823-8-006-007-, MOST 107-2221-E-006-002-, and MOST 107-2218-E-006-001-). We are also grateful to Ms. Bi-Yin. Lin (National Cheng Kung University, 701 Tainan, Taiwan, R.O.C.) for her contribution to the 1H NMR, 13C NMR, and 2D HSQC experiments.
Publisher Copyright:
© 2020 Elsevier Ltd
PY - 2020/2/5
Y1 - 2020/2/5
N2 - Triblock copolymers poly(styrene)-block-poly(isoprene)-block-poly(styrene) (PS-b-PI-b-PS, SIS) and poly(isoprene)-block-poly(styrene)-block-poly(isoprene) (PI-b-PS-b-PI, ISI) with different vinyl structure contents were successfully synthesized by anionic polymerization using a difunctional t-BuLi initiator. The difunctional t-BuLi initiator was prepared from tert-butyllithium (t-BuLi) and 1,3-diisopropenylbenzene, and characterized by 1H NMR, 13C NMR, DEPT135, 7Li NMR, and GC–MS analysis. According to the results of 1H NMR, 13C NMR, and 2D HSQC analysis, the contents of 1,2- and 3,4-addition (vinyl group) structures for PI in SIS and ISI were in the range of 3.7%–94.6%, and depended on the reaction temperature and amount of tetrahydrofuran (THF) added. The Mn and PDI of SIS and ISI obtained by GPC were in the ranges of 13,400–281,000 Da and 1.09–1.24, respectively. The presence of two glass transition temperatures (Tg) on the DSC curve indicated microphase separation of the PI and PS domains. The low Tg was attributed to the PI domain, which was correlated with the vinyl group content in the block copolymer. For vinyl group contents of 6.9% and 94.6% in the SIS triblock copolymer, and 6.6% and 94.2% in the ISI triblock copolymer, the corresponding Tg values of the PI block were −64 °C and 12 °C, and −62 °C and 17 °C, respectively.
AB - Triblock copolymers poly(styrene)-block-poly(isoprene)-block-poly(styrene) (PS-b-PI-b-PS, SIS) and poly(isoprene)-block-poly(styrene)-block-poly(isoprene) (PI-b-PS-b-PI, ISI) with different vinyl structure contents were successfully synthesized by anionic polymerization using a difunctional t-BuLi initiator. The difunctional t-BuLi initiator was prepared from tert-butyllithium (t-BuLi) and 1,3-diisopropenylbenzene, and characterized by 1H NMR, 13C NMR, DEPT135, 7Li NMR, and GC–MS analysis. According to the results of 1H NMR, 13C NMR, and 2D HSQC analysis, the contents of 1,2- and 3,4-addition (vinyl group) structures for PI in SIS and ISI were in the range of 3.7%–94.6%, and depended on the reaction temperature and amount of tetrahydrofuran (THF) added. The Mn and PDI of SIS and ISI obtained by GPC were in the ranges of 13,400–281,000 Da and 1.09–1.24, respectively. The presence of two glass transition temperatures (Tg) on the DSC curve indicated microphase separation of the PI and PS domains. The low Tg was attributed to the PI domain, which was correlated with the vinyl group content in the block copolymer. For vinyl group contents of 6.9% and 94.6% in the SIS triblock copolymer, and 6.6% and 94.2% in the ISI triblock copolymer, the corresponding Tg values of the PI block were −64 °C and 12 °C, and −62 °C and 17 °C, respectively.
UR - https://www.scopus.com/pages/publications/85077514633
UR - https://www.scopus.com/pages/publications/85077514633#tab=citedBy
U2 - 10.1016/j.eurpolymj.2020.109476
DO - 10.1016/j.eurpolymj.2020.109476
M3 - Article
AN - SCOPUS:85077514633
SN - 0014-3057
VL - 124
JO - European Polymer Journal
JF - European Polymer Journal
M1 - 109476
ER -