Does Cross-Link Density of PEO-Like Plasma Polymers Influence their Resistance to Adsorption of Fibrinogen?
2012
Abstract
hin films of PEO-like plasma polymers with different extent of cross-linking were deposited by plasma-assisted vacuum thermal depolymerization of PEO. The films underwent considerable volume changes when in contact with water, i.e., they behaved as hydrogels.
A Flory-Rehner theory of gels corrected for non-Gaussian chain distribution was applied to derive the average molar mass between cross-links. Films with up to ten monomeric units between cross-links were fabricated, this number decreasing to one at enhanced rf power.
Such changes of structure resulted in a three-orders-of-magnitude increase of Young''s modulus. Even highly cross-linked films did not adsorb fibrinogen unless the concentration of the ether groups dropped below 65%.