Unravelling the dynamic crosslinking mechanism in polyborosiloxane

Kurkin, Anatoli1; Lekina, Yulia2; Bradley, David G.3; Seah, Geok Leng1; Tan, Kwan Wee1; Lipik, Vitali1; Hanna, John, V3; Zhang, Xin4,5; Tok, Alfred ling Yoong1

2023-10-01

10.1016/j.mtchem.2023.101677

MATERIALS TODAY CHEMISTRY   影响因子和分区

2468-5194

This study offers a comprehensive investigation into the mechanism behind the dynamic crosslinking of polyborosiloxane (PBS). Despite this material being well known for over 70 years, the origin of PBS's unique viscoelastic properties has been a topic of debate in the literature. Through combined FTIR and solid-state 29Si and 11B MAS NMR analyses, this study provides evidence that the formation of Si-O-B dynamic covalent bonds, along with their associative exchange with neighboring hydroxyl-bearing species (free silanol, water, alcohol, etc.), drives the gelation and viscoelastic behavior of PBS. Results show no indication of hydrogen or dative bonding, instead the low energy barrier for formation and breakage of Si-O-B bonds allows for easy exchange at room temperature. Moreover, the study finds that the viscoelastic properties of PBS can be adjusted by the choice of boron B-O functionality, leading to n-functional dynamic crosslinking through Si-O-B bonds. This research provides a clear understanding of the mechanism of dynamic crosslinking in PBS, resolving long-standing controversies in the field.

Polyborosiloxane Dynamic covalent bonding Supramolecular polymers Fourier transform infrared spectroscopy Nuclear magnetic resonance

SCI ; EI

英语

通讯

EPSRC["EP/K024418/1","AM1"] ; Birmingham Science City[RG57/21] ; Ministry of Education (MOE)["AcRF Tier 1","AcRF Tier 2"] ; AcRF Tier 2[AcRF Tier 2] ; null[EP/M028186/1]

Chemistry ; Materials Science

Chemistry, Multidisciplinary ; Materials Science, Multidisciplinary

WOS:001057831100001

ELSEVIER SCI LTD

20233314546828

Crosslinking ; Fourier transform infrared spectroscopy ; Gelation ; Hydrogen bonds ; Nuclear magnetic resonance ; Nuclear magnetic resonance spectroscopy ; Viscoelasticity

Chemistry:801 ; Physical Chemistry:801.4 ; Chemical Reactions:802.2 ; Chemical Operations:802.3 ; Physical Properties of Gases, Liquids and Solids:931.2

Web of Science

1.Nanyang Technol Univ, Sch Mat Sci & Engn, 50 Nanyang Ave Block N4-1-02-23, Singapore 639798, Singapore
2.Nanyang Technol Univ, Sch Phys & Math Sci, Singapore 637371, Singapore
3.Univ Warwick, Dept Phys, Coventry CV4 7AL, England
4.Southern Univ Sci & Technol, Dept Mech & Aerosp Engn, Shenzhen 518055, Guangdong, Peoples R China
5.Coll Engn, 1088 Hueyuan Ave,8F South Tower, Shenzhen 518055, Guangdong, Peoples R China

Kurkin, Anatoli,Lekina, Yulia,Bradley, David G.,et al. Unravelling the dynamic crosslinking mechanism in polyborosiloxane[J]. MATERIALS TODAY CHEMISTRY,2023,33.

Kurkin, Anatoli.,Lekina, Yulia.,Bradley, David G..,Seah, Geok Leng.,Tan, Kwan Wee.,...&Tok, Alfred ling Yoong.(2023).Unravelling the dynamic crosslinking mechanism in polyborosiloxane.MATERIALS TODAY CHEMISTRY,33.

Kurkin, Anatoli,et al."Unravelling the dynamic crosslinking mechanism in polyborosiloxane".MATERIALS TODAY CHEMISTRY 33(2023).