Stiff Gel Adhesives for Underwater Use


Project ID: D2014-08


Underwater adhesion has several potential medical, household and industrial applications. Generally, underwater adhesives have been prepared using methods that rely on in situ polymerization, covalent crosslinking, or the use of highly specialized biological or biomimetic polymers. Despite current strategies, many challenges have limited the yield and application of biomimetic adhesives including cost, inefficient recombinant protein production, complicated syntheses, the use of potentially harmful oxidants and the need for highly specialized polymer structures. Older strategies have also suffered from deficiencies such as reliance on chemical reactions to set the adhesive, formation of permanent underwater bonds or the requirement for in situ polymerization. There is, thus, a need for more improved underwater adhesives.

Invention Description

Researchers at the University of Toledo, led by Dr. Yakov Lapitsky, have developed a new class of self-assembled adhesive gels that may be prepared from inexpensive and readily available ingredients that may be used for underwater adhesion and controlled release.


•       The invention can be used for the controlled release of fragrances

•       The polymer also be used as an underwater adhesive or adhesive vehicle for other underwater applications

•       The polymer may be used as a bio-adhesive drug carrier

•       The gels form via self-assembly and, thus, require no chemical crosslinking, which minimizes any risk of harmful side effects or reactions

•       The gels are very stiff, which helps immobilize the bonded surfaces

•       The gel adhesives demonstrate excellent adherence to hydrophilic and hydrophobic substrates

•       The gels can be re-dissolved on demand by changing ambient solution conditions

•       Application of the gel adhesive creates an effective barrier for molecular diffusion, suggesting effectiveness as a vehicle for controlled release


•       The polymer, poly(allylamine) (PAH) is FDA approved

•       The ionic crosslinkers, pyrophosphate (PPi) and tripolyphosphate (TPP), are both on FDA’s generally recognized as safe (GRAS) list

•       Preparation of the gel adhesives require common, commercially available polymers and salts that are already approved for use in food and drug delivery technologies

Patent Issued (US 9814778)

Publications:       Huang Y et al., Self-assembly of stiff, adhesive and self-healing gels from polyelectrolytes.  Langmuir, 2014, 7771-7777

Patent Information:
Drug Delivery
For Information, Contact:
Kwaku Opoku
Licensing Associate
The University of Toledo
Yakov Lapitsky
Yan Huang
Controlled Release