Polyelectrolyte multilayers (PEMs), thin polymer films assembled from polyelectrolytes, are used to coat bulk materials to modify surface properties, making the optimization of these properties critical. This study examined the influence of polyelectrolyte molecular weight (MW) and the resulting assembly pattern by creating PEMs with poly(acrylic acid) (PAA) and poly-l-lysine (PLL) at low, medium, and high MW to determine their effects on the surface free energy (SFE) and roughness. Mass increased with MW, as did the ratio of PAA:PLL. Medium MW PEMs were the smoothest, and had the lowest SFE; low MW PEMs were the roughest and had the highest SFE. High MW PEMs were rough while having low SFE. These results demonstrate the tunability of surface properties including SFE and roughness with MW.

• This report represents the work of one or more WPI undergraduate students submitted to the faculty as evidence of completion of a degree requirement. WPI routinely publishes these reports on its website without editorial or peer review.

Creator

• Towle, Elizabeth G

Publisher

• Worcester Polytechnic Institute

Identifier

• E-project-031518-095607

Advisor

• Peterson, Amy M.

Year

• 2018

Date created

• 2018-03-15

Resource type

• Major Qualifying Project

Major

• Chemical Engineering

Rights statement

• In Copyright