: ::981125

: 90

TN effect TN9090

:::UVLPUVLGlanTalor 300 nm(3005 nm)LC cell

: 1.UV

2.LC

3.

4.LBL

Poly(4-vinylpyridine) (PVPy, Mw560,000)

poly(ethyleneimine) (PEI, Mw550,000)

4-hydroxycinnamic acid (purchased from Aldrich)

poly(4-acryloyloxy)cinnamic acid (PCA)

Experimental details1.Synthesis

2. Film preparation

3. Instrumentation and measurement

4. Cell fabrication

SynthesisStep(1) :4-Acryloyloxycinnamic acid preparationPCA (13.12 g, 80 mmol)+NaOH (6.4 g,160 mmol) (40mL) (40mL)

4h

(5~10 9.8mL120mml)

HCl 4-acryloyloxycinnamc acidl(THF)18665%4-Acryloyloxycinnamic acid

Step(2) : Poly(4-acryloyloxy)cinnamic acid (PCA) preparation(20mL)Poly(4-acryloyloxy)cinnamic acid (1g) + AIBN(0.01g)65 12H

50%Poly(4-acryloyloxy)cinnamic acid (PCA)

Synthesis PCA preparation

Film preparation:CaF2NH2PVPy10THFPCA10

Film preparation:LBLPVPy()PCA()

Instrumentation and measurement:1. 300W HgXe LPUVL2.300nm3.GlanTalor 4.LPUVL5.Shimadzu UV-3101PC6.

LPUVLGlanTalor 0.3mWcm-2300 nm(3005 nm)LC cell

Cell fabrication:LPUV

Spacer(20m)TEB30A (TNI = 61 )71GlanTalor LC cell

Results and discussion

3.1 LBL multilayer film formation274nm257nmPVPy- *300nmPCA- *Figure 4. UVvisible absorption spectra of PVPy/PCA film on a quartz substrate with increasing number of bilayers. The inset diagram shows the increase of absorption at 274nm with the number of bilayers.

3.2 Photoreaction in the films(LPUV)300nmPCA10%[2+2]LBLLPUVLPUV

PVPy257nmPVPy

LPUV(A //)(A )LC

DRDR DRDR

3.3 Driving force for PVPy/PCA multilayer fabricationO-H

3.4 Photoalignment properties of the LBL multilayer film(a) (b) 45 45 LC cellLC cell

(Tmax/Tmin)20 LC

Conclusion:PCAPVPyLPUVLPUV