Tunable cross‐linked copolymer networks for improvement of physical performance

Abstract

The ability to tune the physical properties of polymeric materials through the different compositions in copolymer networks is suitable for the strategy of materials accompanied by combined high mechanical strength and stretchability simultaneously. Here, we developed a practical and straightforward strategy of a copolymer network structure via controlling the compositions of the acrylic-based urethane copolymers of diurethane acrylate (DUA) and diurethane cyclic acrylate (DUCA) with hydrogen-bonds through photo-polymerization. The copolymer networks led to the development of a physically cross-linked structure between the amide groups of DUA and/or DUCA and the hydroxyl groups of pentaerythritol ethoxylate (PEEL) by hydrogen-bonds. Based on the rheological analysis, the composition of the copolymer networks had a significant effect on the control of physical properties and development of cross-linked structure and thus led to the tunable comprehensive properties including high elastic modulus, high chain mobility and high recovery performance with a higher proportion of DUCA in the copolymer networks. Consequently, the tunable copolymer networks based on the developed physically cross-linked structure can improve the elastic properties, recovery performance, and healing ability simultaneously, providing significant progress in the fields of coating and adhesive. K E Y W O R D Scopolymers, cross-linked networks, hydrogen-bond, photo-polymerization, polyurethane acrylate | INTRODUCTIONDesigning polymer networks to tune their physical properties is essential for self-healing materials. They have recently been tremendous attention, which has been used in a wide range of fields such as high-performance coating, adhesives, paints, biomedical applications and so forth. [1][2][3][4][5][6] To further expand the applications fields, the recent approaches to achieve self-healing functions give rise to simultaneously not only excellent mechanical properties including strength, toughness, and elasticity but also self-healing behaviors. However, the concurrent combination of high modulus and high flexibility of the materials is still a great challenge because there is a trade-off between these properties. [7][8][9] To achieve the requirement for the self-healing materials, they are widely derived from the introduction of cross-linked polymer networks, which are able to link between

Self-healing polyacrylates based on dynamic disulfide and quadruple hydrogen bonds

“…The latter exhibits self-healing performance mainly through reversible non-covalent interactions or dynamic covalent bonds. The non-covalent bonds include hydrogen bonds, [11][12][13] host-guest interactions, [14][15][16] metal-ion interactions, [17][18][19] etc. The reversible covalent bonds involve dynamic borate bonds, 20,21 Diels-Alder bonds, [22][23][24] disulfide bonds, [25][26][27][28] and others.…”

Tailoring Pressure Sensitive Adhesives with H6XDI‐PEG Diacrylate for Strong Adhesive Strength and Rapid Strain Recovery

“…Urethane acrylate is widely used in stretchable elastomers, [ 19 ] flexible electrochemical devices, [ 20 ] hydrogel [ 21 ] with high flexibility. The aromatic diisocyanate groups act as the hard segment, which can increase tensile strength and stiffness, [ 22 ] while the flexibility and ductility of the polymer can be increased by the poly(ethylene glycol) (PEG) group acting as the soft segment. [ 23 ] In the case of the aromatic diisocyanate groups, they confer mechanical strength and rapid reactivity but are susceptible to oxidatively decomposed by UV light.…”