title: Shifting from hydrogen bond network to π-π stacking: a key mechanism for reversible thermochromic sulfonated poly(ether ether ketone).
abstract: Sulfonated poly(ether ether ketone) (SPEEK) thin film performs reversible thermochromic property by developing the color to be yellowish at the temperature above 190 °C. The detailed analyses based on temperature-dependent techniques suggest the thermal treatment inducing the shifting of the hydrogen bond network between the sulfonated group and the hydrated water molecules to the π-π stacking among aromatic rings in SPEEK chains. Although it is general that the polymer chain packing is unfavorable at high temperature, the present work shows a good example that when the polymer chains can form specific molecular interaction, such as π-π stacking, even in harsh thermal treatment, a rearrangement will effectively occur, which leads to an external stimuli-responsive property.
authors.affiliation: The Petroleum and Petrochemical College, Chulalongkorn University, Bangkok, 10330, Thailand.
authors.forename: Chatchai
authors.initials: C
authors.lastname: Jarumaneeroj
authors.forename: Kohji
authors.initials: K
authors.lastname: Tashiro
authors.forename: Suwabun
authors.initials: S
authors.lastname: Chirachanchai
mesh_terms: D004583:Electrons; D004987:Ethers / Q000737:chemistry*; D006860:Hydrogen Bonding; D007659:Ketones / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D055672:Static Electricity; D013696:Temperature; D014867:Water / Q000737:chemistry
chemical_list: D004987:Ethers; D007659:Ketones; D011108:Polymers; D014867:Water
keywords: SPEEK thin film; aromatic π-π stacking; hydrogen bond network; thermochromic property