Photoinduced phase transition of N-benzylideneaniline liquid crystalline polymer and applications of photodismantlable adhesives

• Published in: Reactive & functional polymers Vol. 174; p. 105247
• Main Authors: Kondo, Mizuho, Uematsu, Takehiro, Ootsuki, Naoya, Okai, Daisuke, Adachi, Hiroki, Kawatsuki, Nobuhiro
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.05.2022; Elsevier BV
• Subjects: Adhesion; Crystal structure; Crystallinity; Glass transition; Light irradiation; Liquid crystal; Liquid crystal polymers; Liquid crystals; N-benzylideneaniline; Phase transitions; Photoinduced phase transition; Thermodynamic properties; Thermophysical properties; Transition points; Ultraviolet radiation; Light irradiation; Liquid crystal; Photoinduced phase transition; Adhesion; N-benzylideneaniline
• ISSN: 1381-5148; 1873-166X
• DOI: 10.1016/j.reactfunctpolym.2022.105247

The liquid crystalline N-benzylideneaniline (NBA) polymer acts as an adhesive, and its bonded pieces detach upon exposure to UV light due to the trans-cis photoisomerization of the NBA moieties and subsequent phase transition of NBA from a liquid crystal polymer to an isotropic polymer. We improved the photoresponsive durability of the polymer and explored the effect of light irradiation on its thermal properties and adhesion stress. We observed that the transition points of the polymer's thermophysical properties (glass transition, liquid crystal-isotropic transition, G" slope, tan δ) shifted to lower temperatures under light irradiation. [Display omitted] •Exposure of NBA to UV light produces phase transition in it.•Exposure of NBA to UV light contributes to change in its adhesive strength.•UV exposure reduces liquid crystal phase and glass transition temperatures of NBA.•Achieving adhesion with NBA can ease implementation of methods that modify it.•Dismantlable adhesives can promote energy-efficient sustainable development.