PEEK-PEEKK copolymer

Poly (ether ether ketone)-poly (ether ether ketone ketone) (PEEK-PEEKK) copolymer... 

X = 0-1, n is a independently integer of more than zero Scheme 10.1 Synthesis routes of PEEK-PEEKK copolymers [23]. 

The other PEEK-PEEKK copolymers with different ratio of DEB/ BFB were prepared by the same method. The relation of melting point of PEEK-PEEKK copolymers vs the mole fraction of BFB was shown in Figure 10.1. 

The results exhibited that the melting point of PEEK-PEEKK copolymers increased with the mole fraction of BFB because of increase of PEEK-PEEKK copolymers rigidity, in other words, the heat-resistance of copolymers increased by introducing more ketone bonds into copolymers. So the properties of PEEK-PEEKK copolymers could be optimized by adjusting the ratio of copolymerization monomers. 

Figure 10.1 The relation of melting point of PEEK-PEEKK copolymers vs the mole fraction of BFB.

One could find from Figure 10.2a and Figure 10.2b that the T of PEEK-PEDEK copolymers increased with increase of biphenyf content of copolymers, but the of PEEK-PEDEK copolymers firstly decreased with increase of biphenyl content until the biphenyl content increased 30% and then of PEEK-PEDEK copolymers gradually increased with increase of biphenyl content. The Tj change of PEEK-PEDEK copolymers was different from that of PEEK-PEEKK copolymers. This phenomenon maybe resulted from different link mode of phenyl, ether bond or ketone bond in polymer chain. 

In this chapter, two general synthetic methods of poly (aryl ether ketone) copolymers were introduced, that is, (1) nucleophilic substitution step copolycondensation of at least two different monomers of bisphenol and at least one dihalobenzoid compound or at least one monomer of bisphenol and at least two different dihalobenzoid compounds (2) electrophilic Friedel-Crafts copolycondensation of at least two different monomer of diphenyl ether and terephthaloyl chloride or at least one monomer of diphenyl ether and terephthaloyl chloride as well as isophthaloyl chloride. Some representative monomers were included. By the method (1), the synthesis and characterization of structural poly (aryl ether ketone) copolymers—poly (ether ether ketone)-poly (ether ether ketone ketone) (PEEK-PEEKK), poly (ether ether ketone)-poly (ether biphenyl ether ketone) (PEEK-PEDEK), poly (ether ether ketone ketone)-poly (ether biphenyl ether ketone ketone) (PEEKK-PEDEKK), poly (ether ether ketone)-poly (ether ether ketone biphenyl ketone) (PEEK-PEEKDK) and poly (ether biphenyl ether ketone)-poly (ether biphenyl ether ketone biphenyl ketone) (PEDEK-PEDEKDK) were discussed. The s5mthesis and characterization of the functional PAEK copolymers, such as liquid crystal poly (aryl ether ketone) copol5oners, poly (aryl ether ketone) copolymers with pendent group of low dielectric constant and poly (aryl ether ketone) copolymers with crosslinking moieties were also discussed in details. These PAEK copolymers showed a lot of special performance and can maybe be applied in optical waveguides, microelectronics, display devices, membrane materials and so on. 

The Tg and change trend of PEEKK-PEDEKK copolymers was the same as those of PEEK-PEDEK copolymers, as shown in Figure 10.3a and Figure 10.3b. 

Both Gharda and Jilin (as Changchun Jilin Super Engineering Plastics Research Co., JSEP) have continued some activities in PAEK. Gharda has patented a low-cost process to produce PEK. JSEP produces PEEKK and PEEK copolymers and has filed patents on various improvements to the polymerisation process. JSEP reports that it will have 1000 tpa production capacity in Liaoning China at the start of 2010. 

Poly (aryl ether ketone) Copolymers 347 Table 10.2 The basic properties of PEEK and PEEKK. 

---