Surface Hybrid Self-Assembly, Mechanism, and Crystalline Behavior of a Carboxyl-Ended Hyperbranched Polyester/Platinum Complex

摘要

The self-assembly of hyperbranched polymers has attracted muchnattention because of their wide application. In this article, we report a new facilensurface self-assembly method for a carboxyl-ended hyperbranched polyesterplatinum complex (HTD-3-Pt) and obtain ordered structural microrods with anlength of 10−20 μm and a width of 1 μm. The length and diameter of the selfassemblednmicrorods could be increased to 300−600 μm and 4−5 μm,nrespectively, by hierarchical self-assembly. The main factors affecting thenmorphology of the self-assemblies, including temperature, time, solvent andnsolubility parameter, and relative humidity were discussed by transmissionreflection polarizing optical microscopy (TRPOM), SEM, and HRSEM. Thenindications for the coordination bond (−COOPt) included the appearance of annew peak at 1606 cm−1 and its shifting to 1634 cm−1 in the FT-IR spectra, thendisappearance of the C 1s peak at about 288.6 eV, and the increase in the O 1snelectron binding energy in the XPS spectra. Furthermore, an interesting crystal property of the HTD-3-Pt self-assemblies wasndiscovered and confirmed by XRD. The study results from the surface self-assembly mechanism suggest that the coordinationninduction of the platinum ion play a key role in driving microphase separation between the intermolecular chains and end groupsnof the HTD-3-Pt to form the microrod self-assemblies. Another interesting finding was that HTD-3-Pt showed a higher catalyticnactivity for hydrosilylation than did a traditional homogeneous catalyst.