Tough and ionically conductive polymer electrolyte composites based on random copolymers with crystallizable side chain architecture.

Polymer electrolyte composites (PECs) with ionic liquids (ILs), which are also known as ion gels, are fabricated using random copolymers with crystallizable side chain architecture, and the effects of the side chain interactions that establish the physically crosslinked network structure in the PECs are studied. The free radical copolymerization of docosyl acrylates (A22) and tert -butyl acrylates (t BA) leads to the synthesis of poly(tert -butyl acrylate- r -docosyl acrylate) [poly(t BA- r -A22)] copolymers with a random sequence distribution. The previous studies on semicrystalline copolymer/IL composites have mostly focused on a limited composition range. The poly(t BA- r -A22) random copolymers over a wider range of compositions readily form mechanically tough and ionically conductive PECs upon incorporation of small amounts of IL (approximately 20 wt%). Thin-film transistors with these PECs as an electrolyte gate dielectric exhibit comparable performance to previously reported transistors using PECs with high IL loading. The composition dependence of the side chain crystallization behavior of the random copolymers and the PECs, markedly distinct from that of main chain crystallization, provides a simple and versatile means to design and tune the electrolyte properties for various device applications. Image 1 • Polymer electrolyte composite comprising semicrystalline copolymers and ionic liquids. • Network formation by random copolymers with crystallizable side chain architecture. • Mechanically tough and ionically conductive electrolyte composite. • Mechanical and electrical properties adjusted by crystallization behavior. • Thin film transistors with polymer electrolyte composites as gate dielectrics. [ABSTRACT FROM AUTHOR]