Advisor : Professor Guey-Sheng Liou Reporter : Tzu-Tien Huang 103 學年度台灣大學高分子科學與工程學系 高分子合成特論 Living Anionic Polymerization of 1,4-Divinylbenzene and Its Isomers Shunsuke Tanaka, Masayoshi Matsumoto, Raita Goseki, Takashi Ishizone, and Akira Hirao, Macromolecules, 2013, 46, 146 Advisor : Professor Guey-Sheng Liou Reporter : Tzu-Tien Huang Date : 2014 / 12 / 26

Advisor : Professor Guey-Sheng Liou Reporter : Tzu-Tien Huang 103 學年度台灣大學高分子科學與工程學系 高分子合成特論 Advisor : Professor Guey-Sheng Liou Reporter : Tzu-Tien Huang Date : 2014 / 12 / 26

Polymerization of Divinylbenzene Cross-linked or Star-branched Polymer Outline Introduction Motivation Experiment Result and Discussion Summary Polymerization of Divinylbenzene Cross-linked or Star-branched Polymer Soluble Polymer Stable Living Polymer

Introduction

Polymerization of Divinylbenzene Isomers Crosslinked Polymer Insoluble Polymer Ion exchange resin Column – Packing agents Pendent vinyl group

Cross-linked Polymer 当溶胶相的反应程度（交联分数）P达到某一临值pc则出现凝胶化。单体平均官能度f Flory-Huggins Theory Gel Point 6 D. J. Worsfold, Macromolecules, 1970, 3, 514 当溶胶相的反应程度（交联分数）P达到某一临值pc则出现凝胶化。单体平均官能度f 决定了临界值pc, 且有•pc=1/(f－1

Star-branched Polymer Poly(isoprenyl) – lithium + m-divinylbenzene L. J. Fetters, Macromolecules, 1978 11, 899

Lithium diisopropylamide (LDA) Soluble Polymer Lithium diisopropylamide (LDA) Growing carbanion ↑ → life time ↓ (Chain transfer by DPA) Reactivity Pendent vinyl groups ＜ DVB monomer Growing carbanion ↑ → Reactivity ↓ (Stabilized 10 π -conjugation.) Teiji Tsuruta, J. MACROMOL. SCI.-CHEM., 1989, A26(8), 1043

Pendent vinyl groupContent Charge Transfer (DPA)

Akira Hirao, Macromolecules, 2011, 44, 4579 Stable Living Polymer In THF at -78 ℃ for 1 min Initiator – Oligo ( α-methylstyryl ) lithium ( sec-BuLi / α-MeSt ) Additive - KOBut Akira Hirao, Macromolecules, 2011, 44, 4579

Anionic Polymerization of 1 in THF at 78 C for 1 min SEC profiles of polymers DVB-1 DVB-3 DVB-4 DVB-5 Initiator sec-BuLi sec-BuLi/α-MeSt /KOBut 12 eq 5 eq

Motivation Soluble Polymer Polymerization of Divinylbenzene Avoid Crossliked or gel (Pendent vinyl group reation) Soluble Polymer High yield High molecular weight Small PDI Stable Living Polymer Expected Polymerization Pendent vinyl group reactivity Time vs Temperature

Experiment

Synthesis of 1,4-Divinylbenzene Scheme Procedure

Preparation of Additives Solution A Solution B Phenol or Alochol THF at −78 ℃ Colorimetric titration 0.5 ~ 0.8 M THF 0.3 M THF 0.05 ~ 0.1 M Potassium Alkoxides and Phenoxides

Polymerization N2 Surrounding - THF -78℃ THF -95 ℃ Initiator - Oligo ( α-methylstyryl ) lithium ( sec-BuLi / α-MeSt ) Additive - Potassium Alkoxides and Phenoxides Monomer - 1,4 – Divinylbenzene 1,3 – Divinylbenzene 1,2 - Divinylbenzene Terminator - Methanol N2

Result and Discussion

Akira Hirao, Macromolecules, 2011, 44, 4579 Previous - KOBut Atom size : K+ ＞Li+ Salt effect > Solvation (Abound of K+ ) ( ion-pair > ion-dissociated ) Steric bulkiness (tert-Butyl) Main Chain ↑ → Pendant vinyl group reativity ↓ (The vinyl group of main chain is electron donating) DVB-5 DVB-4 DVB-3 DVB-1 Akira Hirao, Macromolecules, 2011, 44, 4579

Effect of Metal Alkoxides - Metal [Initiator] = 2~3 ×10-3 M ; [Monomer] = 0.2~0.9 M x LiOBut NaOBut KOBut

Effect of Potassium Alkoxides Reacting alcohol with potassium naphthalenide in THF at −78 ℃ (10 eq) Acetal Oxygen Atom

Effect of Potassium Alkoxides Reacting alcohol with potassium naphthalenide in THF at −78 ℃ (10 eq) pKa small → The ion is stable → Ion-dissociated > Ion-pair Less of steric hindrance

Effect of Potassium Phenoxides and Potassium Pivalate Pivalic acid pKa= 5 → 70% PDI = 1.04 Phenol pKa=10 < Alcohol pKa=16~18

Effect of 18-Crown-6, and P4-tBu Strongly coordinate with K+ Steric bulkiness Soluble polymer but PDI large

Summary of Additive Not Absolutely Steric bulkiness Increase the distance between chain end anion and pendent vinyl group. Basicity Effect the ion stability (Compare the Interaction between Ion-dissociated and ion-pair Soluble Polmer Small PDI Potassium Alkoxides Potassium Phenoxides Potassium Salt (Pivalic acid) Reacting in THF at −78 ℃ Not Absolutely

Effect of Temperature and Polymerization Time In THF at −78 ℃ for 5 min In THF at −95 ℃ for 10~30 min Mn ↑ PDI↑ 30 min 10 min 15 min

Anionic Polymerization of 1,2- and 1,3-Divinylbenzenes Bulky group protect ↓

Anionic Polymerization of Divinylbenzenes Isomers 10 π, 5 resonace 10 π, 5 resonace 8 π, 4 resonace 1,4 and 1,2 - Divinylbenzene is more stable than 1,3 - Divinylbenzene

Stabilization of Chain-End Anion tert-butyl methacrylate -78 ℃ for 3hr (enolate anion) -78 ℃ for 5hr (diphenyl) 1,1-diphenylethylene

Summary

Reaction Time and Temperature Additive Potassium Alkoxides Potassium Phenoxides Potassium Salt (Pivalic acid) Reaction Time and Temperature In THF at −78 ℃ for 1 min In THF at −95 ℃ for 10~30 min Divinylbenzenes Isomers 1,4 and 1,2 - Divinylbenzene is more stable than 1,3 - Divinylbenzene Stabilization of Chain-End Anion tert-butyl methacrylate 1,1-diphenylethylene Soluble Polymer Small PDI High Yield Stable Living Polymer

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