Abstract:

Poly（ether ether ketone） （PEEK） has excellent performance and has been widely used in the high⁃end equipment field； however， the processing window of the PEEK melt is narrow and its processability is poor. Thermotropic liquid crystal polymer （TLCP） is a liquid crystal polymer with excellent dimensional stability， good processing fluidity， and a unique in⁃situ fiber self⁃reinforcing effect. In this study， PEEK/TLCP blends with different contents of TLCP were prepared by mean of an eccentric rotor extrusion mechanism dominated by a volume tensile flow field. The rheological properties， micromorphology， thermal properties and crystallization properties of PEEK/TLCP blends were studied under a tensile flow field. The results indicated that the addition of TLCP effectively broadened the processing range of PEEK under the tensile flow field. This resulted in a decrease in the viscosity of the system by 14.43 % at a low shear rate and by 80.68 % at a high shear rate. Owing to the action of tensile flow field， TLCP formed a fiber structure along the extrusion direction in the PEEK matrix over a wide range of content， and it also could promote the crystallization of the PEEK matrix at a low content. The blend containing 10 wt% TLCP obtained maximum tensile strength of 86.60 MPa， which was 4.6 % higher than that of the PEEK matrix.

Key words: thermotropic liquid crystal polymer, poly（ether?ether?ketone）, volume elongation flow field, in?situ microfibrilation, blending modification