Polyarylethers properties

Table II contains the mechanical properties and the glass-transition temperatures of the styrenic interpolymers, the various polyarylethers, and their 50/50 blends.

The composition dependence of the flexural strength of the aMS/AN-copolymer blend with polyarylether K appears in Figure 13. As the composition of the copolymer increases, the strength first increases, reaches a maximum, and then decreases. It actually exhibits a minimum at about 80% < MS/AN. This behavior can only substantiate earlier suggestions regarding the possible immiscibility of these systems. All of the other mechanical properties indicate that mixtures with polyarylether K may not be miscible but are mechanically compatible. Finally, it is interesting to note that at least one of the pendant chemical groups present on K exists on either of the a-methyl styrene interpolymers. It... 

A study by Yuan and co-workers [26] discusses the influence of molecular weight on the thermal and rheological behaviour of polyarylether ketone. Melt temperature, crystallisation phenomena and rheological properties were compared for polymers with different molecular weights. 

Wires coated with BN-filled polyarylether-polyketone insulation show particularly good recoil properties [88, 89]. Aromatic polysulfones contain dispersed a-BN for improved mold-release properties [90]. 

Detailed properties of the commercial polyarylethers introduced by Union Carbide are beyond the scope of this paper but can be found in the accompanying paper by M. E. Sauers, L. A. McKenna, and C. N. Merriam. Provided here is a basic mechanical property profile of the three polyethers commercially manufactured by Union Carbide. 

Polyetherimide is a hybrid between polyarylethers and polyimides. The imides impart high temperature performance and the inclusion of ether groups allows melt processing. The properties of PEI are in fact closer to PES than to non-melting polyimides. PES and PEI therefore compete... 

Polysulfone PSU is a typical amorphous polyarylether and it shows high heat resistance, nice dimensional stability, and good mechanical properties. However, it has low stress crack resistance and high melt viscosity, which could be overcome by blending with Polyamine PA, a partially crystalline polymer [83]. 

Considerable attention has been devoted to the preparation of fluorine-containing polymers because of their unique properties and high temperature performance (I). Recently we reported the preparation and characterization of novel fluorine-containing polyimides and polyethers which exhibit low moisture absorption and low dielectric constants (2, 3). Fluorinated polyimides absorb 1 wt% water and have dielectric constants of about 2.8 (all dielectric constants reported in this paper were measured at 10 kHz) vtdiereas their non-fluorinated analogs absorb as much as 3 wt% water and have dielectric constants of about 3.2. Fluorinated polyarylethers, which are free of polar groups such as ketones, imides and sulfones, absorb as little as 0.1 wt% water and have dielectric constants less than 2.8. 

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