Polyarylene ethers with improved flowability

#The present invention relates to thermoplastic molding compositions comprising the following components: (A) at least one polyarylene ether, (B) at least one hyperbranched polymer selected from hyperbranched polycarbonates and hyperbranched polyesters, (C) optionally at least one fibrous or particulate filler, and (D) optionally further additives and/or processing aids.

#The present invention further relates to a process for producing the thermoplastic molding compositions of the invention, to their use for producing moldings, fibers, foams, films, or membranes, and to the resultant moldings, fibers, foams, films, and membranes.

#Polyarylene ethers are engineering thermoplastics, and the high heat resistance and high chemicals resistance of these materials leads to their use in very demanding applications. Polyarylene ethers are amorphous and therefore often have inadequate resistance to aggressive solvents. Polyarylene ethers also have high melt viscosity, and this is particularly disadvantageous for processing to give large moldings by means of injection molding. The high melt viscosity is particularly disadvantageous for producing molding compositions with high filler loading or high fiber loading.

#The moduli of elasticity, ultimate tensile strength, and tensile strain at break of the specimens were determined on dumbbells in the ISO 527 tensile test.

#The impact resistance of the products comprising glass fibers was determined on ISO specimens to ISO 179 1eU. The notched impact resistance of the unreinforced products was determined to ISO 179 1eB. In the case of the unreinforced products, tensile strength to ISO 527 was determined instead of ultimate tensile strength.

#Flowability was assessed on the basis of melt viscosity. Melt stability was determined by means of a capillary rheometer. Apparent viscosity was determined here at 350° C. as a function of shear rate in a capillary viscometer (Göttfert Rheograph 2003 capillary viscometer) with a circular capillary of length 30 mm, radius 0.5 mm, with a nozzle angle of 180°, with a diameter of 12 mm for the melt reservoir vessel, and with a preheating time of 5 minutes. The values determined at 1000 Hz are stated.