Chemical Research in Chinese Universities ›› 2009, Vol. 25 ›› Issue (5): 767-772.

• Articles • Previous Articles     Next Articles

Synthesis of Poly(p-phenyleneethynylene)s with Crosslinkable End or Side Groups and Its Solid State Structure and Optical Properties Before and after Crosslinking

WANG Wen-zhong, LIU Zhong-yi and HUANG Peng-cheng*   

  1. Department of Polymer Materials and Composites, School of Materials Science and Engineering, Beihang University, Beijing 100083, P. R. China
  • Received:2008-06-26 Revised:2009-01-07 Online:2009-09-25 Published:2009-12-07
  • Contact: HUANG Peng-cheng. E-mail: huangpc@buaa.edu.cn
  • Supported by:

    Supported by the National Natural Science Foundation of China(Nos.20771030 and 20671025).

Abstract:

Two crosslinkable poly(p-phenyleneethynylene)s(PPEs): poly[2,5-di(2'-ethyl-hexyloxy)-1,4-phenylenee- thynylene] with end-capped vinyl(PPE1) and poly[2,5-di(allyloxy)-1,4-phenyleneethynylene-2,5-di(2'-ethyl-hex- yloxy)-1,4-phenyleneethynylene](PPE2) were synthesized. Via the thermal addition reactions of vinyl end groups of PPE1 and allyloxy side groups of PPE2, crosslinked polymers C-PPE1 and C-PPE2 were obtained, respectively. The two polymers were characterized by wide-angle X-ray diffraction(WXRD), ultraviolet-visible(UV-Vis) absorption, and photoluminescence(PL). The results indicate that in the solid state, the polymer chains of PPE1 were packed with a low degree of crystallinity because of the sterically hindered(2'-ethyl-hexyl)oxy branched side chains, but, because of the introduction of allyloxy side chains, the polymer chains of PPE2 were packed in an order fashion with a high degree of crystallinity. Because of the high crosslinking density in C-PPE2, the formation of aggregates and excimer was hampered by the formed crosslinking network more effectively in C-PPE2 film than in C-PPE1 film.

Key words: Poly(p-phenyleneethynylene); Crosslinkable polymer; Optical property; Packing fashion