Polycondensation of 1,2-cyclohexane dicarboxylic anhydride with a calculated molar excess of di-2-propanolamine led to bis(2-hydroxyalkyl)amide based hydroxy-functional hyperbranched polyesteramides in a straightforward manner. Modification reactions of these polymers with lauric esters was conducted in different synthetic approaches. The obtained polymers were characterized by mass spectrometry, using electrospray ionization (ESI) and matrix assisted laser desorption ionization/timeof-flight (MALDI-TOF) techniques, and by size exclusion chromatography in combination with on-line viscosimetry detection (SEC-DV). Comparison of the experimental results with theoretical calculations showed a satisfactory match on molecular weights and polydispersities with fully modified polyesteramides. These values were found to deviate with unmodified and, to a smaller extent, with partially modified polyesteramides. This phenomenon could be attributed to side reactions of the 2-hydroxypropylamide end groups. The lauric ester modified polyesteramides obtained from either consecutive or simultaneous polycondensation and lauric acid esterification were found to be quite similar in structure and molecular weight distribution. This observation underlined the influence of transesterification reactions under the applied conditions.
h o new difunctionalised [2]catenanes 5 b,c have been synthesised. Oligomers lOc, d containing interlocked rings in the main chain were prepared via Pd" coupling of 5 b with comonomers 9c,d and degrees of polymerization of up to 8 have been reached. These materials were characterized by 'H NMR spectroscopy, fast atom bombardment-mass spectroscopy, gel-permeation chromatography and differential scanning calorimetry.
Hyperbranched polyesteramides (DA2), prepared from hexahydrophthalic anhydride (D) and diisopropanolamine (A) have been characterized, by use of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), field desorption (FD)-MS, and electrospray ionization (ESI)-MS. MALDI of polyesteramides produces protonated molecules. The spectra show a complex chemical composition distribution and end-group distribution which are mainly composed of two series of homologous oligomers DnA(n)+1 - mH2O and DnA(n) - mH2O, where m = 1-2. Signals from protonated molecules DnAn+1 and DnAn are almost absent in the MALDI spectrum, whereas these ions are responsible for the base peak of DnA(n)+1 - mH2O and DnA(n) - mH2O (m = 1-2) clusters in the ESI spectrum. The absence of -OH end-groups signals in the MALDI spectrum is due to a metastable decay of protonated DnA(n)+1 and DnAn ions in the ion source of the MALDI mass spectrometer prior to ion extraction. In-source decay results in the formation of protonated lower DnA(n)+1 - mH2O and DnA(n) - mH2O oligomers and their corresponding neutrals, leading to wrong conclusions concerning the relative end-group distribution as a function of the degree of polymerization and the chemical composition.
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