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4 Structural Characterization of PSPTDA, PS6FDA and PSNTDA

4 Structural Characterization of PSPTDA, PS6FDA and PSNTDA

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SYNTHESES, CHARACTERIZATION



281



PS shows traditional endothermic peak at 400 °C whereas PSPTDA, PSNTDA

and PS6FDA show exotherms. The

spectra of hypercrosslinked

PSNTDA(Figurel8), PSPTDA(Figure l9) and PS6FDA(Figure 20) show peaks at

129ppm sharp peak for proton bearing aromatic carbons and small peak at 146-



282



GANGULY



147 for non proton bearing carbon atoms (31).

However, PSPTDA has molecular overcrowding due to poycyclic aromatic

system as a result it shows three peaks at 161.33, 147.37 and 118.9 ppm for non

proton bearing aromatic carbons. Peak at 42 ppm corresponds the overlapped



SYNTHESES, CHARACTERIZATION



283



peaks for aliphatic carbons. –COOH and –C=O peaks appeared at 215ppm and

220 ppm respectively.



3.5 Low Voltage Scanning Electron Microscopy of a Surface

Modified K-100 Teflon Membrane and Thermalanalysis

Studies of Several Anhydride Modified Nafion 417

Membrane

Kim et.al (32) have shown that with the change of beam energies on the field

emission (FE) SEM images of K-100 TFE surface image from 2, 5 and 20kV,

detail of the surface diminishes progressively with increasing beam due to in-



depth sampling at higher energy. Accordingly, we have studied the modified



284



GANGULY



membrane surface at 2kV beam energy. Gore's expanded PTFE membrane,

K-100, is composed of billions of tiny interconnected continuous fibrils.

Figure 21 is the standard web like morphology of K-100 Teflon membrane

without any coating. Figure 22 shows the top surface of K-100 Teflon membrane



SYNTHESES, CHARACTERIZATION



285



coated with dilute solution of PSPMDA in nitrobenzene and aluminium chloride

as a catalyst. Then several flicking from other side of the membrane gave a very

light coating and heated as mentioned above. The morphology indicates the

presence of foreign material but the pores are intact. The modification of top

surface of K-100 teflon membrane with a layer of PSPMDA (Figure 23) shows

that the web like surface has been filled up with a layer of polymer with some

assembly of nodules and partly as a concave upper surface has shown.

However, some uncovered pores are visible there. The side view of the modified

membrane is shown in Figure 24 . TGA (Figure 25) curves of anhydride modified

Nafion 417 membranes show some improvement of thermal stability compared to

that of unmodified Nafion 417 membrane. Surface modified Nafion 417 show

better thermal stability after 420 °C compare to that of unmodified Nafion

membrane, which confirms the incorporation of PSPTDA and PS6FDA moiety.

DTA data (Figure 26) for Nafion 417 shows sharp exothermic peak where as

PSPTDA, PSNTDA and PS6FDA modified membranes show the reduction of

those peaks and appearance of a small endothermic hump, which is characteristics

of PS Chain.



4. CONCLUSION

Recycling of PS foams can be done to several functionally graded new polymeric

coating materials for fluoro polymers and polystyrene itself. Ionic groups such as

groups -can be incorporated into chemically modified

polystyrene. PSPMDA is compatible with PTFE in terms of its chemical inertness

and thermal stability make it ideal for a wide range of applications where exposure

to harsh chemical conditions or extremes in temperatures are expected, or where

biocompatibility or low chemicals extractable are required. The process has several

advantages, including low cost starting material, easy reaction procedure,

commercial viability as we have studied the technology transfer for the process as

a) Process description and optimization, b) Process Design, c) mechanical design.

The cost for the product, PSPMDA as estimated in 1984 was $8.126/kg. Surface

modified membrane with pore is useful as a new membrane and surface

modification with out pore and ion containing film may be used for Fuel cell,

Battery Industry and Laser Technology.



Acknowledgments:

The author expresses her sincerest gratitude to Prof. Charles E. Carraher of Florida

Atlantic University, USA for his constant encouragement and moral support to

publish this work. Also, thanks to my son Amit for all his help in using my

computer.



286



GANGULY



5. REFERENCES

1 Biswas, M.; Chatterjee, S. J. appl. Polym. Sci. 27, 3851(1982).

2. Biswas, M.; Chatterjee, S.Angew. Makromolek. Chem. 113, 11(1983).

3. Biswas, M.; Chatterjee, S, Euro. Polym. J. 19, 317(1983).

4. Ganguly, S.C.; Hook, J and Bhattacharyya, B.C.;PMSE preprint. 82, 196(2000).

5. Chatterjee, S.; Biswas, M., J.Appl. Polym. Sci., 44,619(1992).

6. Chatterjee, S.; Bhattacharyya, B.C., J. appl. Polym. Sci.33, 2769(1987).

7. Tsyurupa,M.P.; Davankov, V.A.; Rogozhin, S. V., J. Polym. Sci., Polym.Symp.,47,189(1974).

8. Tsyurupa,M.P.;Davankov,V.A.,J.Polym.Sci.,Polym.Chem.Ed.,18,1399(1980).

9. Ganguly, S.C.; Bhattacharyya, B.C. J. Appl. Polym. Sci. 69, 709(1998)

10. Hariharan, D.;Peppas, N.A. J.Membr. Sci.,78,l(1983).

11. Chakrabarti, M. Thesis, I.I.T, KharagpurIndia, 1986.

12. Biswas, M.; Chatterjee, S., J. appl. Polym. Sci. 27, 4645(1982).

13. Biswas, M.; Chatterjee, S., J. appl. Polym. Sci. 29, 829(1984).

14. Biswas, M.; Chatterjee,S.,J.Macromol.Sci.Chem.A21,1507(1984).

15. Chatterjee,S.;Biswas,M., Polymer 26,1365(1985).

16. Higuchi, A.; Iwata, N.; Nakagawa,T., J.Appl.Polym.Sci. 41,709(1990)

17.HiguchiA.;Iwata,N.;Tsubaki,M.;Nakagawa,T.,J.Appl.Polym.Sci.,41,1973(1990).

18. Ganguly, S.C.; Matisons, J.G.;PMSE preprint.,84,347(2001).

19.Xu, H.,South China Teacher’s College,2,141(1981).

20. Frisch, K.C.., J. Appl.Polym.Sci.,689(1974).

21.Millar,J.R.,J.Chem.Soc.,pl311(1960),p.l789(1962),p218(1963).

22. Kolarz, B.J.Polym.Sci.,Polym.Symp.,47,197(1974).

23. Ding, J., J.South China Teacher’s College, 1,44(1981)

24. Vogel, A,I, A Text Book of Quantitative Inorganic analysis, The English Language Book

Society, Longmans Green, London, 1962.

25. Helfferich, F., Ion Exchange, McGraw-Hill, New York,1962.

26. Biswas, M.; John,K.J., Angew.Makromol.Chem.,72,57(1978).

27. Mathieson, A.R.; Shet, R.T., J. Polym.Sci.Part A-14,2945(1966).

28. Davankov, V.A.; Tsyurupa,M.P., Angew.Macromol.Chem.91,127(1980).

29. Bares, J.; Billmeyers, F.W., Experiments in Polymer Science, John Wiley, Inc., New York,

435(1973).

30. Van Krevelen, D.W., Properties of Polymers, Their Estimation and Correlation with

Chemical Structure, Elsevier Scientific Publishing Company, Amsterdam,p.574(1980).

31.Joseph,R.; Ford.W.T.; Zhang.S.; Tsyurupa,M.P.; Pastukhov,A.V.; Davankov,V.A.; J.Polym.Sci.

Polym.Chem.35,695(1997).

32. Kim, K.; Fane, A.G. J. Membrane Sci., 88, 103(1994).



Chapter 20

CONDENSATION COPOLYMERIZATION VIA

Ru-CATALYZED REACTION OF o-QUINONES

OR

WITH

OLIGODIMETHYLSILOXANES

Joseph M. Mabry and William P. Weber*

K. B. and D. P. Loker Hydrocarbon Research Institute

Department of Chemistry, University of Southern California

Los Angeles, CA 90089-1661



1. INTRODUCTION

1.1 Poly(silyl ether)s

Condensation polymers are those in which the repeating unit lacks

certain atoms present in the monomer(s) from which it is formed (1). By

comparison, addition polymers are formed from monomers without loss of

small molecules.

Copolymers of poly(dimethylsiloxane) (PDMS) are of interest for a

variety of applications. Copolymers, which incorporate oligodimethylsiloxane (ODMS) units may have

similar to that of PDMS, but exhibit

no detectable

(2). They are attractive candidates for low temperature

sealants and adhesives. There is also interest in the utility of poly(silyl

ether)s as elastomers (3), sensor materials (4), and polymer membranes (5).

Symmetrical poly(silyl ether)s have been prepared by the condensation

polymerization of dialkoxysilanes and

with loss of alcohol (6-8).



1.2 Transition Metal Catalysis

There is considerable interest in transition metal catalyzed polymerizations (9,10). The instability of poly(silyl ether)s and poly(silyl enol ether)s

in acidic or basic media makes transition metal catalyzed polymerization

287



288



MABRY AND WEBER



under neutral conditions attractive. High molecular weight poly(silyl ether)s

have been obtained by Rh or Pd-catalyzed condensation of bis(silane)s with

diols (figure 1) (11-14). We have reported the Ru-catalyzed addition polymerization of aromatic diketones and

to

yield high molecular weight materials (15,16). Poly(silyl ether)s were recently produced by Pd-catalyzed condensation copolymerization of dihydridosilanes and p-quinones (figure 2) (17).



1.3 Poly (silyl enol ether)s

Poly(silyl enol ether)s have been produced by radical ring-opening

polymerization of trimethylsilyloxy substituted vinylcyclopropanes (18) or

by radical copolymerization of 2-trimethylsiloxy-l,3-butadiene with vinyl

monomers (19-21). In these polymers, the C-C double bond is part of the

polymer backbone, while the trimethylsiloxy group is pendant.



2.



EXPERIMENTAL



and

NMR spectra of

solutions were obtained

on a Bruker AMX-500 MHz spectrometer.

NMR spectra were

obtained with broadband proton decoupling. NONOE with a 60 sec

delay was used to acquire

NMR spectra. Residual

was

used as an internal standard for

and

NMR.

NMR spectra

were referenced to internal TMS. IR spectra of neat films on NaCl

plates were recorded using a Perkin Elmer Spectrum 2000 FT-IR

spectrometer. UV spectra of

solutions were obtained on a

Shimadzu UV-260 spectrometer. Fluorescence spectra of degassed

solutions were taken on a PTI fluorimeter.



CONDENSATION COPOLYMERIZATION



289



GPC analysis of the

of the polymers was performed on a Waters

system equipped with a 401 RI detector. Two 7.8 mm x 300 mm Styragel

columns (HR4 and HR2) in series were used for the analysis. The eluting

solvent was toluene at a flow rate of 0.3 mL/min. The retention times were

calibrated against known monodisperse PS standards: (929,000; 212,400;

13,700; and 794).

TGA of the polymers was measured on a Shimadzu TGA-50 instrument

at a flow rate of 40 cc of

per min. The temperature was increased 4

°C/min from 25 to 800 °C. The

of the polymers was determined on a

Perkin-Elmer DSC-7. The DSC was calibrated from the thermal transition

temperature (-87.06 °C) and mp (6.54 °C) of cyclohexane (22). The

temperature was increased 10 °C/min from -150 °C to 25 °C.

9,10-Phenanthrenequinone (I), 1,2-acenaphthenequinone (II),

benzil (III), 2,3-butanedione (IV), toluene, and styrene were obtained

from Aldrich. Hexamethylcyclotrisiloxane

1,7-dihydrido-octamethyltetrasiloxane (VI), 1,5-dihydridohexamethyltrisiloxane (VII),

and 1,3-dihydridotetramethyldisiloxane (VIII) were purchased from

Gelest. I and II were recrystallized. IV, V, VI, VII, and VIII were distilled.

All reactions were conducted in flame-dried glassware under argon.

(Ru) was prepared from

(23) and activated by

reaction with styrene in a 20 mL Ace pressure tube at 125 °C for 3 min. The

color of the activated catalyst is red (24).

V was prepared by the acid-catalyzed reaction of

with VIII (16).

alt-Copoly(phenanthrene-1,2-dioxy/2,2,4,4,6,6,8,8,10,10-decamethyl1,11-pentasiloxanylene) (IX). I (1.24 g, 6.0 mmol), V (2.13 g, 6.0 mmol),

and activated Ru catalyst were placed in a 25 mL rb flask, which was heated

to 125° C. After 18 h at 125° C, the reaction was stopped. The polymer was

dissolved in THF and was precipitated from methanol. In this way, 3.0 g,

88.8 % yield of material,

100/16,900,

°C was obtained.

NMR

-0.011 (s, 12H), 0.013 (s, 6H), 0.322 (s, 12H), 7.59 (m, 6H),

8.30 (d, 2H, J = 7.5 Hz), 8.64 (d, 2H, J = 7.5 Hz).

NMR

0.86,

1.05, 122.24, 123.33, 124.90, 126.20, 127.76, 129.77, 136.68.

NMR 21.77 (s, 1Si), -21.04 (s, 2Si), -11.22 (s, 2Si). UV

309(20,830),

297(19,240), 272(34,650), 258(92,930), 226(24,980). TGA: IX is stable in

to 200 °C. Between 200 and 650 °C, catastropic decomposition occurs.

90 % of the initial weight is lost. Between 650 and 800 °C, no additional

weight is lost. IX is stable in air to 150 °C. Between 150 and 550 °C, 69 % of

the initial sample weight is lost. To 800 °C, no additional weight is lost.

alt-Copoly(acenaphthene-1,2-dioxy/2,2,4,4,6,6,8,8,10,10-decamethyl1,11-pentasiloxanylene) (X) was prepared by reaction of II (0.49 g, 2.7

mmol) and V (0.96 g, 2.7 mmol) as above. After precipitation with

methanol, 1.2 g, 82.8 % yield,

°C was

obtained.

NMR 0.11 (s, 18H), 0.320 (s, 12H), 7.41 (d, 2H J = 6.5 Hz),



290



MABRY AND WEBER



7.50 (t, 2H, J = 6.5 Hz), 7.61 (d, 2H, J = 6.5 Hz).

NMR -0.14, 1.05,

119.97, 126.02, 127.20, 127.40, 127.55, 129.51, 134.35.

NMR -21.90

(s, 1Si), -20.60 (s, 2Si), -11.49 (s, 2Si). UV

327(17,523),

239(19,958). TGA: X is stable in

to 200 °C. Between 200 and 225 °C, 15

% of the initial weight is lost. Between 225 and 400 °C, an additional 10 %

of the initial weight is lost. Between 400 and 625 °C, an additional 65 % of

initial weight is lost. X is stable in air to 125 °C. Between 125 and 225 °C,

40 % of the initial sample weight is lost. From 225 to 550 °C, an additional

35 % of the initial weight is lost. To 800 °C, no additional weight is lost.

alt-Copoly(phenanthrene-l,2-dioxy/2,2,4,4,6,6,8,8-tetramethyl-l,9tetrasiloxanylene) (XI) was prepared by reaction of I (1.04 g, 5 mmol) and

VI (1.41 g, 5 mmol) as above. After precipitation, 2.1 g, 85.6 % yield,

was obtained.

NMR -0.10 (s, 12H),

0.25 (s, 12H), 7.55 (m, 4H), 8.24 (t, 2H, J = 7 Hz), 8.60 (t, 2H, J = 7 Hz).

NMR

0.05, 0.80, 122.21, 123.27, 124.89, 126.19, 127.68, 129.68,

136.61.

NMR

-21.09 (s, 2Si), -11.22 (s, 2Si). UV

310(5473), 258(23,846). TGA: XI is stable in

to 225 °C. Between 225

and 675 °C, catastrophic decomposition occurs and 89 % of the initial weight

is lost. To 800 °C, no additional weight is lost. XI is stable in air to 225 °C.

Between 225 and 575 °C, 59 % of the initial weight is lost. To 800 °C, no

additional weight is lost.

alt- Copoly (acenaphthene-1,2-dioxy/2,2,4,4,6,6,8,8-tetramethyl-1,9tetrasiloxanylene) (XII) was prepared by reaction of II (1.00 g, 5.5 mmol)

and VI (1.55 g, 5.5 mmol) as above. After precipitation, 2.1 g, 82.3 % yield,

was obtained.

NMR

0.08 (s,

12H), 0.30 (s, 12H), 7.38 (t, 2H J = 7.5 Hz), 7.48 (d, 2H, J = 7.5 Hz), 7.59

(d, 2H, J = 7.5 Hz).

NMR -0.14, 1.03, 119.97, 120.98, 126.03, 126.65,

127.20, 134.33, 136.79.

NMR

-20.47 (s, 2Si), -11.42 (s, 2Si). UV

315(4142), 241(5705). TGA: XII is stable in

to 225 °C.

Between 225 and 600 °C, catastrophic decomposition occurs and 90 % of the

initial sample weight is lost. To 800 °C, an additional 5 % of the initial

weight is lost. XII is stable in air to 200 °C. Between 200 and 550 °C, 80 %

of the initial sample weight is lost. To 800 °C, no additional weight is lost.

XIII was prepared by reaction of III (1.47 g, 7.0 mmol) and V (2.50 g,

7.0 mmol) as above. After precipitation, 3.4 g, 85.6 % yield,

was obtained.

NMR: [-0.22, -0.20, -0.18,

-0.15, -0.13, -0.11, -0.09, -0.07, -0.04, -0.01, -0.00, 0.04, 0.06, 0.08] (30H),

4.64 (s, 0.35H), 4.82 (s, 0.17H), [7.05, 7.09, 7.10, 7.12, 7.18, 7,19, 7.21,

7.22, 7.24, 7.30, 7.77] (10H).

NMR: -1.31, -0.78, -0.60, -0.36, -0.26,

0.08, 0.67, 0.77, 1.04, 78.98, 126.84, 127.05, 127.18, 127.37, 127.43,

127.55, 127.58, 128.70, 129.35, 129.54, 136.18, 137.98, 141.23, 142.35.

NMR: [-22.13, -22.10, -22.07, -22.01, -21.98, -21.91, -21.85, -21.76, -21.66,

-21.51] (3Si), [-13.21, -13.03, -12.83, -12.41] (2Si). UV

301-



CONDENSATION COPOLYMERIZATION



291



(4826), 230(3823). TGA: XIII is stable in

to 150 °C. Between 150 and

400 °C, 10 % of the initial weight is lost. Between 400 and 625 °C, an

additional 80 % of the initial weight is lost. XIII is stable in air to 125 °C.

Between 125 and 550 °C, 72 % of the initial weight is lost. To 800 °C, no

additional weight is lost.

XIV. IV (0.60 g, 7.0 mmol), V (2.50 g, 7.0 mmol), were reacted as

above in an Ace pressure tube. After precipitation, 2.7 g, 87.1 % yield,

was obtained.

NMR: 0.01 (s, 18H), 0.03

(s, 9H), 0.07 (s, 3H), 1.04 (d, 2.3H, J = 4 Hz), 1.10 (d, 2.5H, J = 4 Hz), 1.71

(s, 0.8H), 1.74 (s, 0.4H), 3.61 (m, 0.6H), 3.75 (m, 0.3H).

NMR: -0.55,

-0.14, 1.03, 17.68, 17.73, 19.99, 71.45, 72.80, 129.22, 133.52.

NMR:

-22.02 (s, 1Si), -22.01 (s, 1Si), -21.96 (s, 1Si), -14.10 (s, 0.5Si), -14.07 (s,

0.5Si). TGA: XIV is stable in

to 200 °C. Between 200 and 625 °C,

catastrophic decomposition occurs.

XV was prepared by reaction of IV (0.62 g, 7.2 mmol) and VI ( 2.04 g,

7.2 mmol) as above. After precipitation, 2.17 g, 81.6 % yield,

was obtained.

NMR: 0.02 (s, 6H), 0.026 (s, 6H),

0.033 (s, 4.5H), 0.04 (s, 4.5H), 0.08 (s, 3H), 1.05 (d, 2.2H, J = 4.5 Hz), 1.11

(d, 3.1H, J = 4.5 Hz), 1.72 (s, 0.5H), 1.75 (s, 0.2H), 3.62 (m, 0.6H), 3.76 (m,

0.3H).

NMR: -0.61, -0.19, 0.96, 17.57, 17.68, 19.87, 71.39, 72.74,

128.41, 132.02.

NMR: -22.14 (m, 2Si), -14.23 (m, 2Si). TGA: XV is

stable in

to 175 °C. Between 175 and 625 °C, catastrophic decomposition

occurs; 90 % of initial weight is lost.

XVI was prepared by reaction of IV (0.86 g, 10.0 mmol) and VII (2.09

g, 10.0 mmol) as above. In this way, 2.5 g (84.9% yield) of polymer with

°C, was obtained.

NMR: 0.046 (s, 3H),

0.052 (s, 3H), 0.06 (s, 4.5H), 0.07 (s, 4.5H), 0.11 (s, 3H), 1.08 (d, 2.2H, J =

5 Hz), 1.14 (d, 2.6H, J = 5 Hz), 1.75 (s, 0.8H), 1.78 (s, 0.4H), 3.63 (m,

0.6H), 3.78 (m, 0.3H).

NMR: -0.53, -0.29, -0.11, 1.03, 17.65, 17.73,

19.96, 71.48, 72.84, 128.79, 133.93.

NMR: -22.00 (m, 1Si), -14.16 (m,

2Si). TGA: XVI is stable in

to 175 °C. Between 175 and 600 °C,

catastrophic decomposition occurs; 90 % of initial weight is lost.

XVII was prepared by reaction of IV (0.86 g, 10.0 mmol) and VIII

(1.34 g, 10.0 mmol), as above. In this way, 1.9 g (86.2% yield) of polymer

with

was obtained. NMR 0.067 (s,

5H), 0.072 (s, 5H), 0.11 (s, 2H), 1.08 (d, 2.4H, J = 5 Hz), 1.13 (d, 3H, J =

3.5 Hz), 1.74 (s, 0.4H), 1.78 (s, 0.2H), 3.64 (m, 0.6H), 3.77 (m, 0.5H).

NMR

-0.56, -0.16, 1.02, 17.68, 19.89, 19.97, 71.45, 72.78, 126.55,

135.50.

NMR

-14.10 (s). TGA: XVII is stable in

to 175 °C.

Between 175 and 650 °C, catastrophic decomposition occurs; 90 % of initial

weight is lost.



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