Processable, reversible, and reusable 100 % bio-based pressure sensitive adhesives using nanostarch

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2024-09, Vol.495, p.153392, Article 153392
• Main Authors: Pi, Bong Soo, Lee, Kyoungmun, Song, Chaeyeon, Jeon, Byeongju, Han, Youngkyu, Choi, Siyoung Q.
• Format: Article
• Language: English
• Subjects: 100 % bio-based adhesive; Amylopectin; Nanostarch; Non-crosslinked PSA; Pressure sensitive adhesive
• ISSN: 1385-8947
• DOI: 10.1016/j.cej.2024.153392

[Display omitted] •A 100 % bio-based PSA is formulated with nanostarch, CNF, glycerol, and sorbitol.•No chemical crosslinking is exploited for cohesive strength and easy processing.•Adhesion strength is comparable with conventional petrochemical-based products. We developed a 100 % bio-based pressure sensitive adhesive (PSA) possessing strong adhesion, as well as reusability, recyclability, and on-demand removability. The adhesive formulation is based on a colloidal mixture of starch (specifically amylopectin) nanoparticles and cellulose nanofibrils, combined with an aqueous solution of sorbitol and glycerol. Optimization of water supply and substitution of water with hygroscopic glycerol were implemented to address the challenges caused by the use of high water contents in hydrogels. By leveraging physical crosslinking through hydrogen bonding, we achieved high adhesion strength, reversibility, and reusability with 100 % bio-based materials. The optimal formulation demonstrates excellent rheological and adhesion properties, which are comparable to petrochemical-based adhesives in terms of tack, peel strength, and shear strength. While there are areas for further optimization, this work provides a foundational step towards a more sustainable adhesive industry.