α

ω-dibromo-terminated polystyrenes were prepared by atom transfer radical polymerization(ATRP). Then

the azidation and "click" chemistry reaction were carried out to convert α

ω-dibromo-terminated polystyrenes to α

ω- dialdehyde-terminated telechelic polystyrenes. For comparison

the dialdehyde polystyrene was also prepared by one-step

in which the terminal bromines of the dibromo-terminated polystyrene were directly substituted by

p-hydroxy

benzaldehyde. The terminal aldehyde functionality of the dialdehyde polystyrene (

M

n

NMR

= 2480g· mol

-1

) prepared by the azidation and "click" chemistry reaction could reach 79%

which was 54% higher than the one-step method's. Experimental results also showed that polymers with low-molecular weights were easier to obtain high functionalities than the ones with high molecular weights.