Application Of Hyperbranched Polymer In Nylon 6 And PET Processing

Hyperbranched polymers have attracted considerable and increasing interests during recent years because of their unique properties. Unlike dendrimers prepared by stepwise synthesis, hyperbranched polymers need a simple preparation process. Owing to the unique structure and properties, hyperbranched polymers has been used in many fields, such as blending, coating curing agent, composite material modification etc.1. Study on the aromatic hyperbranched polyesters used as processing additives in nylon 6 melt spinning processThe synthesized aromatic hyperbranched polyesters with different contents were blended with nylon 6 in a twin-screw extruder. The effects of hyperbranched polyesters on the crystallization behavior of nylon 6 were investigated using wide-angle X-ray diffraction (WAXD) and DSC methods. WAXD results indicated the crystal forms of nylon 6/hyperbranched polyesters were changed compared with those of pure nylon 6. In the blends,γ-crystal form content was more than that in pure nylon 6, and theα-crystal form content was a little less than that in pure nylon 6. DSC results showed that the blends had a little effect on the crystallization temperature, but the crystallization rate was improved compared with pure nylon 6. Owing to the decrease of the melt viscosity of nylon 6/HBP blends, the melt spinning temperatures of blends could be decreased dramatically, therefore the thermal degradation of nylon 6 could be reduced.2. Study on the aromatic hyperbranched polyesters used as processing additives for PET used as bottleThe synthesized aromatic hyperbranched polyesters with different contents were blended with PET in a twin-screw extruder. The effects of hyperbranched polyesters on the crystallization behavior of PET were investigated using non-isothermal DSC, wide-angle X-ray diffraction (WAXD) and polarizing microscopy (POM). The results showed that the hyperbranched polyesters had a certain effect on the crystallization temperature, crystallinity, crystallization rate and nuclear mechanism of PET, but had no effect on the melt point. Furthermore, small crystallites were observed by WAXD and POM. SEM micrographs showed the homogeneous dispersion of hyperbranhced polyesters in scale of tens to hundreds of nano-meters in PET matrix. The addition of hyperbranched polymer had no effect on the mechanical of PET.