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The nucleophilic ring opening addition reaction of phenol groups towards oxazoline units has been used for the preparation of hyperbranched poly(ether amide)s. For this the AB 2 monomer 2-(3,5-bishydroxyphenyl)-1,3-oxazoline was synthesized and converted in a highly branched polymer in bulk or solution at temperatures above 190 • C. The resulting hyperbranched polymers exhibit a degree of branching of 50%, as verified by high-resolution NMR spectroscopy, and are highly soluble in polar organic solvents, for example DMF and DMAc, with low solution viscosity. Their glass transition temperatures are in the region of 170 • C and degradation does not start below 300 • C. Melt rheology measurements revealed a predominantly elastic behaviour with a relatively high viscosity at low frequency. A lower melt viscosity was achieved by end group modification. Hyperbranched poly(ether amide)s with phenolic and acetate end groups are fully miscible with linear polyamide 6. When a small amount of the hyperbranched material is added to the PA6 matrix a significant reduction of the melt viscosity could be achieved without changing the mechanical properties of the matrix polymer.

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poly(2-methylpropene) (PIB) macromonomers (P3 (VB); P5) is described:In this communication a novel synthetic route to a-tert-butyl-o-[p-vinylphenyll-terminated and P5Attempts to synthesize such macromonomers in both one-and two-step syntheses are described. The one-step method using 4-chloromethylstyrene/AlR3 as initiating system for the polymerization of 2-methylpropene did not yield linear macromonomers but rather highly branched products. The alternative two-step synthesis using l-(2-bromoethyl)-4-chloromethylbenzene (BCB) or BCB/AgSbF, as initiator also failed to yield the desired products. Successful synthetic routes, optimised on the basis of model experiments with low molar mass compounds, are also described for preparing the above macromonomers. Both of these routes involve isopropenylterminated PIB, which is easily assessible by Inifer technique followed by dehydrohalogenation. Friedel-Crafts alkylation of phenol by the terminal olefin group of PIB, followed by subsequent esterification of the phenolic end-groups with 4-vinylbenzoyl chloride, affords the macromonomer P3(VB). Conversion of the terminal olefin group of PIB into a primary alcohol using 9-bora[3,3, I]-bicyclononane/H202, followed by esterification, yields the macromonomer P5. ' ) BASF,