Surface Modification Of Particles And Their Dispersion Properties In Pet

The polyester are expected to has many excellent properties when ultrafinepowders are added. These properties include the anti-ultraviolet and anti-agingproperties if nano TiO2 particles are added in the polyester fiber, and good openingperformance if micro SiO2 particles are incoperated in the polyester film. However,the inorganic ultrafine powers have a strong tendency to agglomeration, and as theresult, it is difficult to obtain an ideal composite with desired properties..In this paper, mechanical and chemical methods were used to treat the ultrafinepowders in order to evenly distribute the ultrafine powders in the EG. The mechanicalmethods include the ultrasonic, mixing, milling machine, ball grinder etc. The particlesize analysis showed that the sand mill machine and ultrasonic can make ultramicropowders dispersed satisfactorily; The silane coupling agent KH570 and titanate-estercoupling agent NDZ-201 were as the chemical modifier, and the results showed thatthe surface modifier can be grafted onto the powder surface and modified particlestructure can be characterized by infrared spectroscopy (IR), thermogravimetry (TG);The ultrafine powders can be dispersed stably in EG if nano-TiO2 and micro-SiO2particles are treated with 4% NDZ-201 and 2% KH570 respectively.The PET/particle composite materials were prepared using in-situ polymerizationafter the ultrafine powders were treated using a method which is a combination ofmechanical and chemical treatments. The powder dispersion was evaluated usingscanning electron microscopy (SEM) and such properties as crystallinity, thermal andanti-ultraviolet behaviors were tested using X-ray diffraction (XRD), differentialscanning calorimetry (DSC) and UV spectrophotometer. The results showed that themodified powders can be more evenly dispersed in PET compared to the unmodified counterpart and the powder agglomeration was found to be reduced; The degree ofcrystallinity was increased and the glass transition temperature (Tg), thecrystallization temperature (Tc) as well as the melting point (Tm) of the PET/particleblend shown a downward trend with the addition of the ultrafine powder.The spinning experimental results showed that the anti-UV polyester fiberscontaining 0.5%wt of particles, made via in-situ polymerization as well as themasterbatch processes, showed acceptable spinnability and drawability and the fibersthus obtained showed adequate tensile strength and elongation at break, which isindicative of a good particle distribution.