화학공학소재연구정보센터
Journal of Adhesion, Vol.82, No.10, 945-971, 2006
Adhesion properties of lightly crosslinked solvent-swollen polymer gels
Polymer gels are crosslinked polymer networks, highly swollen with solvent. For practical gel applications adhesion to a wide range of substrates over a broad range of temperatures is desired. In this article the adhesive properties of two types of solvent-swollen elastomers were studied, utilizing a combination of tack, contact mechanics, and peel adhesion methods. The first gel was a crosslinked polybutadiene swollen with common polymer plasticizers, while the second was a commercially available silicone with high extractables content. Nominally, these solvent-swollen materials exhibit similar adhesive characteristics to nonsolvent swollen elastomers including: (1) an increase in tack adhesion energies with increasing pull-off rates and decreasing temperatures in the rubbery region, (2) qualitative correlation between the rheological loss tangent for the gel and the gel adhesion energy, (3) fibrillation and extension during adhesion testing for gels with a shear modulus value less than 10(5)Pa in the plateau region, and (4) a decrease in the adhesion energy with increasing crosslink density. However, the presence of solvent in the elastomer can lead to solvent exclusion effects that degrade tack adhesion and must be considered for gel design in practical applications.