The interfacial behavior of third and fourth generations of hyperbranched polyesters (HBP3 and HBP4) with 32 and 64 hydroxyl-terminal groups was studied with scanning probe microscopy. The molecular adsorption on a bare silicon surface of both hyperbranched polymers was described in the terms of the Langmuir isotherm. A higher adsorption amount under an identical adsorption condition was found for lower generation HPB3. The shape of HBP3 molecules within an adsorbed layer evolved from a pancake with a thickness less than 1 nm for very low surface coverage to densely packed wormlike bilayer structures with a thickness of about 3 nm for the highest surface coverage. The molecules of the fourth generation, HBP4, hold a stable, close-to-spherical shape with a diameter of 2.5 nm throughout the entire range of surface coverage including both dense monolayers and isolated molecules. High intramolecular flexibility of HBP3 molecules as compared with constrained mobility of bulkier branches of HBP4 is considered to be responsible for different surface behavior.

We suggest a simple, one-step procedure to prepare a homogeneous functional polymer layer grafted to a silicon oxide substrate. We demonstrate that robust and uniform nanoscale layers can be fabricated from the functionalized hyperbranched polymer with dual nature of terminal branches:  alkyl chains combined with epoxy-functionalized chains. A branched chemical architecture with multiple epoxy groups provides the grafting capability inducing surface functionality along with simultaneous hydrophobization of the surface. We suggest the monolayer structure of these grafted films. These hyperbranched monolayers are thicker than conventional alkyl-chain self-assembling monolayers (SAMs) and demonstrate elastic properties typical for cross-linked polymer layers. The surface is composed of epoxy groups randomly distributed within alkyl peripheral branches. Grafted hyperbranched polymer layers are homogeneous on a nanoscale without signs of the microphase separation and heterogeneous domain surface structures usually observed for two-component SAMs.