Influence of Hyperbranched Polyesters on the Surface Tension of Polyols

Abstract

The influence of hyperbranched polyesters with different functional end groups on the surface tension of mixtures with an oligo(ester diol) was investigated. The temperature dependence of the surface tension of the pure components and of the mixtures was measured by a modified Wilhelmy balance technique. The results indicate that the surface tension of the pure hyperbranched polyesters strongly depends on the functionality of the end groups. The functionalization of the hydroxyl end groups by short alkyl chains (methyl, tert-butyl) reduced the surface tension depending on the degree of substitution. The surface tension of the mixtures with the hydroxyl-terminated hyperbranched polyester was slightly increased at higher concentrations of the hyperbranched polymer compared to the surface tension of the pure ester diol. On the other hand, the surface tension of mixtures could be considerably decreased using 1% of hyperbranched polyester polyols partially substituted with short alkyl chains. In that case, the modified hyperbranched polyesters act as surface active agents. On the molecular level, the enrichment of the modified hyperbranched polyester in the surface region was proven by X-ray photoelectron spectroscopy measurements.

Physical and thermal properties of UV curable waterborne polyurethane dispersions incorporating hyperbranched aliphatic polyester of varying generation number

“…Hyperbranched polymers have also been described in several applications, ranging from processing additives to thermoset system components [23,24]. Now-a-days, many studies about waterborne polyurethane have been published but there is little information about the use of hyperbranched polymers in UV curable waterborne coatings.…”

Stimulus responsive fluorescent hyperbranched polymers and their applications

“…Furthermore, the feature of convenient one-pot synthesis of HBPs makes them particularly desirable candidates for bulk-material and special applications. With the persistent efforts of the scientists, HBPs have been exploited advantages in nanoscale catalysis, supramolecular assembly, photorefractive holography, adhesive coating, rheological modifications, surface chemistry, magnetic polymeric materials [8][9][10][11][12][13][14][15], and so on.…”

Hyperbranched Conjugated Polymers: Postfunctionalization

“…Inherently, hyperbranched polymers (HBPs) offer a possibility for postfunctionalization, as in a polymer formed from n AB 2 units, n reactive B groups will remain. Described from a theoretical point of view as an intermolecular condensation of AB x monomers by Flory in 1952, HBPs have been exploited over the last several years in live-cell imaging, solar cells, drug delivery systems, and surface chemistry …”

“…Described from a theoretical point of view as an intermolecular condensation of AB x monomers by Flory in 1952, 7 HBPs have been exploited over the last several years in live-cell imaging, 8 solar cells, 9 drug delivery systems, 10 and surface chemistry. 11 Herein 12 we present polyfunctional and well-soluble conjugated HBPs prepared from the AB 2 monomers 2a and 2b. The properties of the formed HBPs (3a and 3b in Scheme 1), accessible on a multigram scale, are tuned by a subsequent Pd-catalyzed alkynylation reaction.…”