Since electroluminescence(EL) for an organic semiconductor was reported

Poly(phenylenevinylene)(PPV) derivates are the most promising materials for organic light-emitting diodes(OLEDs).To realize more brightness and luminescence efficiency

the strong electron-withdrawing CN groups were introduced to conjugated side chains because cyano group posses strong electron-deficiency and electron-transporting charac-teristics.Moreover

bigger side chains structures could reduce aggregation state in solid film

which is suitable to OLEDs.A new alternating copolymer DiCN-PPV containing bis(2-phenylacrylonitrile)-2

5-dibromo-1

4-phenylene) and 1-(heptyloxy)-4-(octyloxy)-2

5-divinylbenzene was successfully synthesized via Heck polymerization with moderate yields.Since Poly(phenylenevinylene)(PPV) posses strong electron-rich and hole-transporting characteristics and cyano group is obviously a electron-deficiency material

the donor-acceptor conjugated structures could change the energy band gap and light-emitting color.The polymer was cha-ractered by

1

H-NMR

MS

element analysis and GPC.It possesses good thermal stability(

T

d

=247℃) and is adequate for the fabrication processes of optical-electric devices.In the optimized polymerization reaction conditions

the polymer of DiCN-PPV(

M

n

=1.76×10

4

P

d

=1.9

production rate 50%) was soluble in common organic solvents.The absorption spectrum of DiCN-PPV solution shows two absorption peak and that of film shows one absorption peak

which means a new energy level was formed after energy transfer between donor and acceptor units.Moreover

the onset of absorption edge is located at 623 nm in solid film

which is red shift by 80 nm than that in solution because more aggregation conformation were formed in solid state.Photoluminescence(PL) spectra coincide with above conclusion and the fluorescence peaks of DiCN-PPV in solution and solid film

were at 573 nm and 645 nm

respectively.Because of λ

max FL

=645 nm in solid film

it can be a potential red light-emitting material for fabrication of organic light-emitting diodes(OELD).