Influence on molecular geometry and chain conformation on properties of polyelectrolyte multilayers

The layer-by-layer (LbL) method of self-assembly is a versatile technique for fabricating thin polymer films. This thesis compares the properties of LbLfilms composed of different weak polycations. Slight perturbations in film assembly conditions can lead to large differences in film properties. Polyion bacisity and architecture are less understood variables. The polycations used are of similar chemical composition but different molecular geometries and basicity. Films studied were composed of poly(acrylic acid) (PAA) in combination with linear poly(ethylene imine) (LPEI), poly(allyl amine hydrochloride) (PAH), branched poly(ethylene imine) (BPEI), or poly(amidoamine) (PAMAM) dendrimer, generation four, amine surface. Various properties of these films are compared; including film thickness, chemical functional group availability, and film composition. Carboxylic acid group ionization is found to increase with assembly pH, and PAA content is found to decrease. PAH, the most basic of the polycations, forms films that are the thinnest and the most ionized while PAMAM films have the most free free acid groups and form the thickest films.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Materials Science and Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2007

Author dc:creator

• Zacharia, Nicole Suzan

Advisor dc:contributor.advisor

• Paula T. Hammond.

• Materials Science and Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/39324

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/39324