Abstract:
This study examines the surface-dependent formation of interpolymer complexes
(IPCs) by the layer-by-layer (LBL) deposition method. The materials used in this analysis are poly(acrylic acid) (PAA) combined with cellulose ethers, namely methyl cellulose
(MC), hydroxypropyl cellulose (HPC), and hydroxyethyl cellulose (HEC), and poloxamers
PX188 and PX407. PMMA, PS, and glass surfaces have been used to study the influence
of hydrophobicity and hydrophilicity on IPC growth and its properties. Through contact
angle measurements, PMMA and PS were found to be hydrophobic and glass hydrophilic.
It was revealed by gravimetric analysis that IPC films reveal the highest growth on PMMA
substrates, followed by PS and glass. Both the molecular weight of HEC and the hydrophobicity of the surface considerably affected the growth. Hydrogen-bonded complexation
was evident by means of FTIR spectroscopy, while changes in some characteristic absorption bands demonstrated the extent of interactions between polymers. Scanning electron
microscopy showed that variations in the microstructure of surfaces occur; PAA-MC and
poloxamer complex layers were well organized on hydrophobic substrates. Thus, the experimental results showed surface properties, especially hydrophobicity, to be important for
IPC growth and structure. These findings contribute to the understanding of IPC behavior
on different substrates, thus giving insights into applications in drug delivery, coatings,
and functional films.
