Abstract
Mechanically interlocked polymers(MIPs)are promising candidates for the construction of elastomeric mate-rials with desirable mechanical performance on account of their abilities to undergo inherent rotational and translational mechanical movements at the molecular level.However,the investigations on their mechanical properties are lagging far behind their structural fabrication,especially for linear polyrotaxanes in bulk.Herein,we report stretchable poly[2]rotaxane elastomers(PREs)which integrate numerous mechanical bonds in the polymeric backbone to boost macroscopic mechanical properties.Specifically,we have synthesized a hydroxy-functionalized[2]rotaxane that subsequently participates in the condensation polymerization with diisocyanate to form PREs.Benefitting from the peculiar structural and dynamic characteristics of the poly[2]rotaxane,the representative PRE exhibits favorable mechanical performance in terms of stretchability(～1200％),Young's mod-ulus(24.6 MPa),and toughness(49.5 MJ/m3).Moreover,we present our poly[2]rotaxanes as model systems to understand the relationship between mechanical bonds and macroscopic mechanical properties.It is concluded that the mechanical properties of our PREs are mainly determined by the unique topological architectures which possess a consecutive energy dissipation pathway including the dissociation of host-guest interaction and con-sequential sliding motion of the wheel along the axle in the[2]rotaxane motif.
基金项目
国家自然科学基金(22122105)
国家自然科学基金(22071152)
国家自然科学基金(21901161)
上海市自然科学基金(20ZR1429200)
上海市自然科学基金(22YF1400800)
Starry Night Science Fund of Zhejiang University Shanghai Institute(SN-ZJU-SIAS-006)
NETL
NSTL
万方数据