JOURNAL OF POLYMER SCIENCE: PART A: POLYMER CHEMISTRY DOI 10.1002/POLA
TABLE 1 Characterization of the Fluorinated Polymers (FPSD 1–4)
PFS in Feed
(mol %)a
Conversion
(%)
PFS Composition
(mol %)
Gel Fraction
(%)e
Tg (ꢀC)c
Td (ꢀC)d
b
Polymer
Mn
Mw/Mn
FPSD 1
FPSD 2
FPSD 3
FPSD 4
a
0
25
50
75
93.5
92.3
94.6
93.4
0
2436
3574
3087
2679
2.01
1.88
2.13
1.98
102.3
110.5
105.2
112.6
258.1
251.2
236.1
230.5
99.53
99.26
99.14
99.11
24.6
50.7
76.5
d
Molar ratio of [PFS] / [PFSþPFDM].
Onset temperature for 5% weight loss measured by TGA with a heat-
ing rate of 10 ꢀC/min in nitrogen.
b
c
Number average molecular weight determined by GPC.
e
Glass transition temperature of uncross-linked polymer measured by
Gel fraction was obtained from the ratio of the weight of samples
DSC with a heating rate of 10 ꢀC /min in nitrogen.
from chloroform and the initial weight.
Fluorinated Polystyrene Derivates (FPSD 1-4)
FPSD 1
TMS): d (ppm) 7.31 (2H, s), 7.21 (2H, s), 6.85 (4H, s), 4.21
(1H, s), 3.92 (1H, s), 3.32 (1H, s), 2.87 (1H, s), 2.71 (1H, s),
2.46–2.44 (2H, m), 2.04–2.02 (4H, m). 13C NMR (500 MHz,
CDCl3, TMS): d (ppm) 159.3, 157.3, 143.0, 140.9, 139.7,
136.8, 132.5, 131.7, 129.6, 128.3, 126.1, 123.4, 121.4, 115.3,
114.7, 69.1, 64.4, 50.4, 44.7, 44.5, 21.9. 19F NMR (500 MHz,
CDCl3, CFCl3): d (ppm) ꢁ64.70 (6F, d), ꢁ143.85 (4F, m),
ꢁ155.51 (4F, m), ꢁ161.36 (1F, m). Anal. Calcd for
FSDM (2 g, 3.53 mmol), 10 mL of toluene, and azobisisobu-
tyronitrile (AIBN) (0.02 g, 0.12 mmol) were introduced to a
round-bottom flask fitted with a condenser. The mixture was
swept by nitrogen, and then heated to 70 ꢀC. After 6 h, the
obtained mixture was poured into a large excess of methanol
(20 mL). The resulting white precipitate was collected by fil-
tration, washed thoroughly with methanol, and dried at
room temperature under vacuum.
C
34H19F15O3: C, 53.68; H, 2.50, F, 37.50. Found: C, 54.96; H,
2.58; F, 35.69.
Yield: 1.87 g, 93.5%. Mn ¼ 2436; Mw/Mn ¼ 2.01. IR (KBr,
cmꢁ1): 1120–1300 (CAF), 928.9 ( ). 1H NMR (500 MHz,
CDCl3, TMS): d (ppm) 7.29 (2H, s), 7.19 (2H, s), 6.80 (4H, s),
4.18–4.16 (1H, d, 10.5Hz), 3.87 (1H, s), 3.28 (1H, s), 2.83
(1H, s), 2.68 (1H, s), 2.60–2.56 (1H, m), 2.16–2.07 (2H,m).
13C NMR (500 MHz, CDCl3, TMS): d (ppm) 159.1, 157.3,
143.6, 142.6, 142.0, 140.4, 132.3, 131.8, 129.4, 128.6, 127.9,
125.8, 124.1, 123.4, 122.2, 121.1, 115.5, 114.6, 69.1, 64.1,
50.3, 45.0, 44.8, 21.9. 19F NMR (500 MHz, CDCl3, CFCl3): d
(ppm) ꢁ64.57 (6F, d), ꢁ143.81 (2F,m), ꢁ155.48 (2F, m).
Anal. Calcd for C26H16F10O3: C, 55.12; H, 2.83, F, 33.57.
Found: C, 55.75; H, 2.88; F, 31.29
FPSD 4
Yield: 93.4%. Mn ¼ 2679; Mw/Mn ¼ 1.98. IR (KBr, cmꢁ1):
1120–1300 (CAF), 928.2 ( ). 1H NMR (500 MHz, CDCl3,
TMS): d (ppm) 7.30 (2H, s), 7.17 (2H, s), 6.84 (4H, s), 4.26
(1H, s), 3.96 (1H, s), 3.35 (1H, s), 2.90 (1H, s), 2.76 (1H, s),
2.41–2.39 (4H, m), 2.01–2.00 (8H, m). 13C NMR (500 MHz,
CDCl3, TMS): d (ppm) 159.2, 157.3, 142.9, 141.5, 139.5,
138.9, 136.9, 132.4, 131.9, 129.6, 128.6, 128.0, 125.9, 124.1,
123.5, 122.5, 121.2, 115.2, 114.6, 69.2, 64.0, 50.3, 45.2, 45.0,
21.8. 19F NMR (500 MHz, CDCl3, CFCl3): d (ppm) ꢁ64.58 (6F,
d), ꢁ143.85 (8F, m), ꢁ155.52 (8F, m), ꢁ161.43 (3F, m).
Anal. Calcd for C50H25F25O3: C, 52.26; H, 2.18, F, 41.38.
Found: C, 53.24; H, 2.43; F, 40.24.
The other polymers from both FSDM and PFS with the corre-
sponding feed ratio of [PFS]/[PFSþPSDM] were prepared
using the same procedure outlined above listed in Table 1.
Their characterizations are as follows.
Film Preparation for the Measurement of Refractive
Index
To prepare negative-type fluorinated photoresists 1-4 (NFP
1-4), the FPSD 1-4 solution were prepared in cyclopentanone
(60–80 wt %), PI was added as the initiator (8 wt % relative
to polymer). The NFPs were filtered by a syringe through a
0.22 lm Teflon membrane filter and spin-coated onto a sili-
con wafer substrates. The resulting films (3–7 lm in thick-
ness) were baked at 90 C for 30 min, then irradiated by UV
light (1000 V) for 8 min. The films were finally baked at 100
ꢀC for 1 h.
FPSD 2
Yield: 92.3%. Mn ¼ 3574; Mw/Mn ¼ 1.88. IR (KBr, cmꢁ1):
1120–1300 (CAF), 928.9 ( ). 1H NMR (500 MHz, CDCl3,
TMS): d (ppm) 7.31 (6H, s), 7.24 (6H, s), 6.82 (12H, s), 4.19
(3H, s), 3.89 (3H, s), 3.29 (3H, s), 2.85 (3H, s), 2.69 (3H, s),
2.60–2.57 (4H, m), 2.09–2.05 (8H, m). 13C NMR (500 MHz,
CDCl3, TMS): d (ppm) 159.2, 157.3, 142.9, 140.8, 139.5,
136.8, 132.3, 131.8, 129.5, 128.0, 125.9, 123.4, 121.1, 115.2,
114.6, 69.2, 64.2, 50.3, 44.9, 44.6, 21.6. 19F NMR (500 MHz,
CDCl3, CFCl3): d (ppm) ꢁ64.57 (18F, d), ꢁ143.85 (8F, m),
ꢁ155.52 (8F, m), ꢁ161.26 (1F, m). Anal. Calcd for
ꢀ
Photopatterning
For good adherence of NFP, the Si/SiO2 wafer was first ultra-
sonically cleaned in organic solvents and then soaked in an
C86H51F35O9: C, 54.55; H, 2.70, F, 35.15. Found: C, 55.37; H,
ꢀ
etchant consisting of H2SO4:H2O2 ¼ 7:3 at 90 C for 30 min.
2.38; F, 33.41.
Then the Si/SiO2 wafer was rinsed in deionized water, dried
using nitrogen gas, and spin-coated with NFP. The thickness
of the NFP layer on the substrate was controlled by the spin-
ning speed and solid content of NFP.
FPSD 3
Yield: 94.6%. Mn ¼ 3087; Mw/Mn ¼ 2.13. IR (KBr, cmꢁ1):
1120–1300 (CAF), 929.9 ( ). 1H NMR (500 MHz, CDCl3,
764
WILEYONLINELIBRARY.COM/JOURNAL/JPOLA