Polymerization of styrenes with pendant aminophosphazenes and fluorescence behaviors of their Eu3+ complexes

Eur. Polym. J. Vol. 33, No. 6, pp.841-847. 1997 0 1997 Elwier

PII: S00143057(%)00228-5

Science Ltd. All rights reserved Printed in Great Britain OOM-3057/97 $17.00 + 0.00

POLYMERIZATION OF STYRENES WITH PENDANT AMINOPHOSPHAZENES AND FLUORESCENCE BEHAVIORS OF THEIR Eu3+ COMPLEXES KENZO INOUE,* YUTAKA

SASAKI, TOMOYUKI

ITAYA and TEIICHI

TANIGAKI

Department of Applied Chemistry, Faculty of Engineering, Ehime University, 3 Bunko-cho, Matsuyama 790, Japan (Received 15 April 1996; accepted 9 May 1996)

Abstract-Radical polymerizations of novel styrenes with pendant penta(3-dimethylaminopropylamino)(SPDAP) and penta(Zdimethyl aminoethoxy)cyclotriphosphazene (SEAP) in various solvents and the fluorescence behavior of complexes of Eu3+ with these cascade materials were studied. The conversion of SEAP increased on going from THF to ethanol, whereas the conversion of SPDAP in ethanol showed the lowest value. The application of the Kamlet-Taft equation to the conversion suggested that the polymerization of SPDAP and SEAP is primarily affected by the hydrogen bond interaction. ‘C NMR spectra of SEAP showed that the peak of the b-carbon in the vinyl group shifted downfield as the conversion increased. This suggests that the interaction between the monomer and solvents brings about a change of polymerizability of SEAP. A similar downfield shift was observed for SPDAP in ethanol,

suggesting that SPDAP also has a high polymerizability. The inherent viscosities of poly(SEAP) and poly(SPDAP) in ethanol were found to be considerably higher than those in THF. This result and the kinetic treatment of polymerization suggest that the side arms on the phosphazene ring in ethanol are expanded due to the hydrogen bond interactions with the solvent, and that the propagation is sterically hindered, especially for the polymerization of SPDAP with relatively long side arms. This might be responsible for the low conversion observed for the polymerization of SPDAP in ethanol. When Eu’+ ions were added to SPDAP, a significant increase in fluorescence intensity of Eu3+ was observed. The plot of fluorescence intensity vs the concentration of SPDAP suggests the formation of a 2:l SPDAP-Eu3+ complex. For the polymer-Eu’+ complex, a similar increment of the intensity was observed. From the chemical shifts of side arms in the monomer-Eu’+ complex, the structure of the complex is discussed. 0 1997 Elsevier Science Ltd

INTRODUCTION Poly(organophosphazenes) composed of an inorganic main chain, -kN-, are an important family of polymers which have attracted much interest as a result of unique properties attainable through a wide variety of organic pendant groups [1,2]. Recently, we reported the preparation and polymerization of styrene derivatives with pendant cyclotriphosphazene [3--S]. The monomers and polymers containing pendant chlorocyclophosphazene moiety can easily be modified by introducing organic groups such as oligo(oxyethylene) chains into the remaining Cl atom. These polymers with five arms per monomer units are considered to be a polymer of an octopus molecule and expected to possess new properties and functionalities originating from a number of side chains [5]. In the last two decades, polymers containing lanthanide ions have been extensively investigated because of many intriguing properties such as photoand electroluminescence. [6-91. Trivalent lanthanides bind preferentially to hard bases such as oxygen and nitrogen donor ligands. Most lanthanide cations exhibit luminescence in which both spectra and life*To whom all correspondence

should be addressed.

times are sensitive to the coordination environment of the metal ions. So far, various macrocyclic ligands

such as cryptands and calixarenes as well as acyclic host molecules containing bipyridine units and polyaminocarboxylate have been prepared and the fluorescence behavior of their lanthanide ion complexes has been investigated [IO-151. The lanthanide ions are also known to form complexes with alkyl amines such as 1,2-propanediamine and diethylenetriamine, although they are highly hygroscopic crystalline and hydrolyze rapidly [ 16, 17. It is of great interest whether polymers of octopus molecules carrying a number of oxygen and/or nitrogen donor act as ligand for lanthanide ions. In this paper, we report the polymerization of new styrene derivatives with 3-dimethylaminopropylamino and 2-dimethylaminoethoxy groups as the side arm on the pendant phosphazene ring and. the fluorescence behavior of complexes of monomers and polymers with Eu’+ ions. EXPERIMENTAL Materials

Hexachlorocyclotriphosphazene (HCP) was kindly sup plied by Nihon Seika Co. and purified by recrystallization from n-hexane. p-Hydroxystyrene was pnpared from p-hydroxycinnamic acid [3]. 3-Dimethylaminopropylamine, 841

K. Inoue er al.

842

2-dimethylaminoethanol, and triethylamine were distilled from NaOH before use. Solvents were distilled from appropriate drying reagents before use. EuCl.6H~0 was purchased from Nakarai tesque and used without further purification. Monomer synthesis A solution of 3-dimethylaminopropylamine (12.0 g, 0.12 mol) and TEA (23.5 g, 0.23 mol) in THF was added into a stirred solution of (4+inylphenoxy)pentachlorocyclotriphosphazene (VPCP, 5 g, 0.012 mol)) in THF, which was prepared from the reaction of HCP with 4-hydroxystyrene [3]. After stirring for 36 hr at room temperature, the reaction mixture was filtered and the solvent evaporated under reduced pressure. The residue was dissolved in ether and washed with water. The solvent was removed, and the residue was chromatographed on silica gel (Fuji Davison, NH-DM-1020; hexane-chloroform, 5: I, and then hexanechloroform-methanol, 5: I : I) to afford SPDAP as a viscous oil. Yield, 78%. IR(neat); 3600-3000, 1620, 1600, 1500, 1250-1150 cm-‘. ‘HNMR(CD,OD, see Fig. 8); 1.48-1.62 (m. 4H, -CHZCHZCHZ-, spatially proximate to vinylphenoxy group), I .62-l .78 (m, 6H, -CHZCH,C&--), 2.15-2.27 (m, 50 H, -N(CH& and 4 protons of -C&N(CH&, spatially proximate to vinylphenoxy group), 2.3c2.41 (m, 6H, -C&N(CH&), 2.60-2.71 (m, 4H, -NHCHz), 2.83-2.95 (m, 4H, -NHC& spatially proximate to vinylphenoxy group), 2.96-3.07 (m, ZH,-O-P-NHCHx), 5.05-6.71 (m, 3H, -CH=CH& 7.2&7.4l(m, 5H, arom. H). Anal. Calcd for CUH~~N,IOIP& 52.16; H, 9.55; N, 23.96. Found, C,52.13; H, 9.60; N, 23.92. SEAP: into a stirred solution of VPCP (5 g, 0.012 mol) was added the sodium salt of amine, which was prepared from 2-dimethylaminoethanol (10.7 g, 0.12 mol) and NaH (4.7 g, 0.12 mol) in THF at room temperature. After being stirred for 3 hr, the reaction mixture was worked-up as described above. Chromatography gave a pale yellow oil. Yield, 70%. IR(neat): 3600-3000, 1620, 1500 cm-‘. ‘HNMR(CDCI$ 2.43-2.72 (m. IOH, 2.05-2.42 (m, 30H, -N(CH,)z). -C&N=), 3.524.33 (br, IOH, -OCHz-). 5.00-6.75 (-CH=C&, 3H), 7.02-7.15 (br s, 5H, aroma. H). Anal. Calcd for ClBH5,N806P3C, 48.41; H, 8.27; N, 16.13. Found C, 48.12; H, 8.25; N, 16.21. Polymerization

The conversion was calculated from the disappearance of vinyl protons in ‘H NMR spectra. In a typical experiment, a solution of SEAP (0.25 mol/L) and AIBN (0.8 mmol/L) in THF was placed into a glass tube The sample was degassed by a freeze-thaw technique and sealed off. The polymerization was carried out in a bath maintained at 70°C. After a definite time, the tube was opened and a standard solution of benzaldehyde was added. Then the solvent was removed, and the mixture dissolved in CDCh. The conversion was

calculated from the peak height of vinyl groups to that of formyl proton before and after polymerization. Copolymerization of SPDAP with MMA with AIBN initiator in ethanol was run at 70°C in tubes sealed under vacuum. The copolymer was purified by reprecipitation

from THF to 7:3 n-hexane-ether. The content of SPDAP in the copolymer was determined by elemental analysis. Fluorescence

Methanol was of spectroscopic grade from Wako. A solution of the weighed EuCl,.6H20 (0.1 mmol/L) in methanol was added to a solution of SPDAP (5 x lO-4 mol/ L) in methanol. For poly(SPDAP) and poly(SPDAP-coMMA), a mixture of methanol and THF (95:5) was used. All measurements were made at room temperature using an emission bandwidth of 5 nm. Measurements

‘H NMR spectra were obtained from a JEOL PMX60Si and JEOL GSX-270 spectrometers. “C NMR spectra were recorded on a JEOL GSX-270 spectrometer. FT-IR spectra were recorded on a Jasco FTIR-230 spectrometer. Fluorescence spectra were recorded on a Shimadzu RF-5000 spectrometer. The intrinsic viscosity was measured in an Ubbelohode type viscometer at 25°C. RESULTS AND DISCUSSION

Polymerization

of SEAP

and SPDAP

The monomers, SEAP and SPDAP, were prepared by the displacement of the P-Cl group of 2-(4-vinylphenoxy)pentachlorocyclotriphosphazene, which was prepared from hexachlorocyclotriphosphazene and 4-hydroxystyrene, with the sodium salt of dimethylaminoethoxide and dimethylaminopropanediamine in the presence of triethylamine at room temperature for 3 days, respectively. The spectroscopic data and elemental analysis of the monomer have given satisfactory results. Time-conversion relationships are shown in Fig. 1 for the polymerization of SPDAP and SEAP in ethanol and THF initiated with AIBN. The polymerizations of these monomers are apparently affected by changing the solvents. The plots are linear up to 25% conversion without exhibiting an induction period. The molecular weights of the polymers, unfortunately, could not be determined by GPC due to the trap in the polystyrene columns. The polymers have amphiphilic properties being soluble in a number of organic solvents such as THF, benzene, methanol, and water. Interestingly, a solution of poly(SPDAP) and poly(SEAP) ([polymer] = 0.03 mol/L) in water showed a lower critical solution temperature (T,) at 67 and 7O”C, FH=CH,

TEA

*

NH2(CH2)JN(CHJ)21TEA

0

\&/

e

0,P YR

or NaO(CH2),N(CH3),

N' *N

HPC

CL II I/Cl C~p~N”RCl

N' *N

R,II I/R R/5,*,9,

VPCP

-R

SPDAP : SEAP : Scheme I. Preparation of SPDAP and SEAP.

-NWCH,W(CWI -O(C~zhN(C~~h

Polystyrenes with pendant aminophosphazenes

843

50

40 z

v 6 3

2 30 .I r f c 20 s

E

10

0

Time

0

6

4

2

0

2

4

6

10

8

XYZf

@)

Fig. 1. Time-conversion curves for the polymerization of SPDAP (0, 0) and SEAP (A, A) at 70°C. (0) and (A), in ethanol; (0) and (A), in THF. [SPDAP] = SEAP] = 0.25 mol/L. [AIBN) = 0.8 mmol/L.

Fig. 2. Observed vs calculated conversion for the polymerization of SPDAP (0, 0) and SEAP (A). (0) and (A), the conversion in solvents listed in Table 1; (a), the conversion of SPDAP in solvents except for ethanol and 2-propanol.

The T, is known to depend on the balance between the ability of the formation of polymer-water hydrogen bonds and the inter- and intramolecular hydrophobic forces, i.e. the former raises T,, while the latter lowers T,. It appears that the interand intramolecular interactions of poly(SPDAP) is somewhat stronger than that of poly(SEAP). The solvent effects on the polymerization were summarized in Table 1. The polymerization of SPDAP was sensitive to the solvent properties compared to that of SEAP. The results obtained in ethanol are complex, i.e. ethanol was the most effective solvent for the polymerization of SEAP but displayed opposite role for the polymerization of SPDAP. The conversions were not directly related with parameters such as dielectric constants and Er values of solvents. Kamlet and Taft [18] have shown that the solvent effects on the reactivity (XYZ) could be expressed by the following equation, XYZ= XYZo+sn* +aa+b/I, where n*, a, and fl denote solvent polarity-polarizabilities, solventhydrogen bond donor acidities, and solvent-hydrogen bond acceptor basicities, respectively. As shown in Fig. 2, plots of the calculated values for the polymerization of SEAP vs the conversions gave

a straight line. For the polymerization of SPDAP a rather poor correlation was obtained. However, if the correlation is limited to the four solvents (THF, dioxane, benzene, and chlorobenzene), then the correlation improves significantly. The rate of polymerization could be expressed by XYZ,, = 8.1 -3.37r* + 6.Oa -2.88 for SEAP in solvents examined and XYZ,, = 7.3 + 2.3n* - 5.68 for SPDAP in aprotic solvents. From the comparison of coefficients of each term, the polymerization seems to be primarily affected by the monomer- and polymersolvent hydrogen bond interactions. The deviation observed for the polymerization of SPDAP in ethanol and 2-propanol suggests that additional solvent effect(s) caused by hydrogen bond interactions is operative (aide post). 13CNMR spectra are very useful to clarify whether the reactivity of monomer is affected by a and /I factors of solvents. As shown in Table 1, the j-carbon in vinyl group of SEAP shifted to the downfield going from THF to ethanol, the order of which is in agreement with that of conversions. This suggests that the interaction between SEAP and solvents is one of the factors to govern the polymerizability of the monomer. This also implies that the reactivity

Table 1. Solvent affects on polymerizations of SPDAP and SEAP”

Solvent THF Dioxane Benzene CBd 2-Propanol Ethanol

Conversion (%/hr) SEAP

0.576

OL -

6 0.556

SPDAP 5.5

0.553

-

0.588

-

0.379 0.100 0.07 I 0.92 0.77

6.4 8.1 8.5 5.1 3.0

0.703 0.505 0.540

“At 70°C. hFrom TMS. Wearured at 25°C. Chlorobenzene.

0.695 0.826

Chemical shift”

[VI Poly(SPDAP)

Poly(SEAP)

SPDAP

SEAP

4.5

112.0

113.0

0.10

0.05

5.6 5.7 5.9 8.0 9.2

112.2 112.3 112.3 112.6 112.8

113.1 113.1 113.2 113.4 113.6

0.10 0.11 0.11 0.1 0.15

0.06 0.06 0.05 0.08 0.08

844

K. Inoue et al.

of growing polymer radicals might be affected by changing of solvents. If the relation of the polymerizability and chemical shifts is also operative for the polymerization of SPDAP, the rate of polymerization in alcohol should be faster than that in other solvents. However, this is not true. As reported previously, for the polymerization of multiarmed monomers, the conformational change of growing polymer chains caused by the interaction between side arms on the phosphazene ring and solvents affects significantly the propagation and termination processes [3,4]. In order to obtain information on the conformational change depending on the hydrogen bond interactions between the polymer and solvents, the intrinsic viscosity of poly(SPDAP) and poly(SEAP) was measured. For both polymers, the intrinsic viscosities in alcohol are higher than those in solvents such as THF and benzene. The results suggest that the polymer chains take an extended conformation in alcohol, whereas a random coil conformation is favorable in the latter solvents. This implies that in alcohol the side arms on the phosphazene ring is liable to form hydrogen bonds with the solvent rather than intramolecular interaction of side arms, which might bring about the extension of polymer chains. Contrary to this, in aprotic solvents, it is likely that side arms aggregate each other so that the polymer chains take a random coiled conformation. For the polymerization of vinyl monomers with relatively small pendant groups, the formation of the coiled conformation of the growing polymers might contribute to the acceleration of the polymerization due to the entanglement of polymer radicals (gel effect) and/or the increases in local monomer concentration around radicals. However, the propagation of polymer radicals with a bulky pendant group might become restricted as the chains grow, and compete with the termination by primary radicals in addition to mutual termination. Inspection of CPK molecular model of these monomers reveals that the side arms in SPDAP have enough length to approach vinyl group but not for SEAP, suggesting that the arms of SPDAP interfere to some extent with the propagation process. If the primary radical termination is operative, the orders of monomer and initiator should be greater than 1 and less than 0.5, respectively [19]. Kinetic studies in ethanol showed that the orders of initiator concentration determined from straight lines shown in Fig. 3 were 0.38 and 0.17 for the polymerization of SEAP and SPDAP, respectively (Fig. 4). The orders of monomer concentration were found to be 0.95 and 0.74 for the polymerization of SEAP and SPDAP, respectively (Fig. 4). The observed orders of the initiator concentration suggest that primary radical termination occurs, especially for the polymerization of SPDAP. However, the order less than 1.0 of monomer concentration was not consistent with the expected value for the mechanism including conventional primary radical termination process. The unexpected order of monomer concentration for the polymerization of SPDAP implies that the chain transfer of polymer radicals to the solvent might occur much more predominantly than the propagation. Judging from the CPK model and orders of monomer and initiator

e

-12 -8

-6

-1

In

III

-5

-4

(mol/L)

Fig. 3. Plots of the rate of polymerization vs initiator concentrations. (a), SPDAP; (A), SEAP. In ethanol. [SPDAP] = [SEAP] = 0.2 mol/L.

concentrations, it seems that the side arms in growing poly(SEAP) radicals might influence the propagation to a lesser extent, whereas the polymerization of SPDAP in ethanol is sterically hindered by dimethylamino groups in side arms that are spatially located in close proximity to growing polymer radicals. Thus, the opposite behavior observed for the polymerization of SEAP and SPDAP in ethanol might be explained by the difference of steric hindrance caused by side arms, which originated from side arms-ethanol hydrogen bond interactions. Copolymerization

The copolymerization of SPDAP (MI) and MMA (M2) (Fig. 5) gave highly viscous polymers which exhibited a characteristic -P=Nstretching absorption between 1240 and 1160 cm-‘. The GPC of copolymers with less than 25 mol% of SPDAP showed one peak, but copolymers with high contents of SPDAP units could not be determined by

-2.5

-2

-1.5 -1 In [M] (mom)

Fig. 4. Plots of the rate of polymerization

-0.5

vs monomer

concentrations. (a), SPDAP; (A). SEAP. In ethanol. [AIBN] = 0.8 mmoI/L.

Polystyrenes with pendant aminophosphazenes

I 1 0.5 mole fraction [MI] in monomer feed

I

0

Fig. 5. Copolymerization of SPDAP (MI) with MMA (Mz) in ethanol (0) and THF (0). [SPDAP] + [MMA] = 0.6 mol/L. [AIBN] = 0.8 mmol/L.

GPC. The copolymer compositions of poly(SPDAPco-MMA) were determined by elemental analysis. From the Mayo-Lewis integral equation, the monomer reactivity ratios in ethanol and in THF were calculated to be rl = 0.12, r-2= 0.62 and rl = 0.25, r2 = 0.57, respectively. This result indicates that growing SPDAP radicals preferentially add to MMA, particular in ethanol. The difference of the monomer reactivity ratio might be due to the steric hindrance caused by the expanding of side arms of growing SPDAP radicals, as described above. The Alfrey-Price parameters calculated from rl and r2 obtained in ethanol are Q = 0.62, and e = - 1.22. These values appear to be reasonable, at least qualitatively, in spite of having relatively bulky and polar pendant group.

845

1

700

600

Fig. 6. Fluorescence spectra of the complex of SPDAP with Eu3+ ion in methanol. L, = 396 nm. [SPDAP] = 5 x lo-‘mol/L. [Eu’+] = 1 x lo-*mol/L. (-) SPDAP-Eu’+ complex; (. . .) Ed+.

phosphazene ring and shielded from the interaction with methanol, which is known to quench the luminescent excited state. The metal-to-ligand ratio for the complexes was determined by means of the molar ratio method. As shown in Fig. 7, the SPDAP to Eu3+ ratio was found to be 2: 1. The same result was obtained for SEAP-Ed+ complexes. It is known that primary or secondary amines quench the excited state in a similar manner of quenching mechanism of water [ 171. This implies that the participation of NH group in the formation of complex is unlikely. Furthermore, the fluorescence intensity of the SPDAP-Eu3+ system is somewhat stronger than that of the SEAP-E3+ system. Thus, it appears that Eu3+ ion forms the complex with dimethylamino group but not NH group in the arms.

Fluorescence

It is of great interest whether SPDAP, SEAP, and their polymers act as hosts to lanthanide ions. We first examined the luminescence mode of the monomers used as ligands for Eu’+ ions. Although SEAP- and SPDAP-Eu3+ complexes underwent slow decomposition, it was possible to obtain data on the emission. This implies that the complexes are rather stable compared to the Eu3+ complexes with aliphatic diamines such as ethylenediamine and triethylenediamine, which can exist only under rigorously anhydrous conditions [lo, 11, 171. As shown in Fig. 6, the fluorescence intensity of the SPDAP-Et?+ complex was moderately enhanced compared to that of Eu3+ alone, while the wavelengths of peaks were not affected by the presence of SPDAP. It is well known that the fluorescence properties of lanthanide ions are strongly affected by the coordinative environment, i.e. the fluorescence intensities of ‘D,,-‘F, at 592 nm and sDr7F2 at 618 nm are sensitive to the circumstances around metal ions. The relative intensity Fs2/Fsls observed for Eu3+ alone varied when SPDAP were added, suggesting that Eu3+ ions were trapped by the side chains on the

0

5

10

15

[monomery[EuS*] Fig. 7. Plots of fluorescence intensity vs the concentration of SPDAP-Eu’+ (a) and SEAP-Eu’+ complexes (A).

846

K. Inoue et al

The enhancement of fluorescence intensity and/or stability of the complex originated from the “polymer effects” such as entanglement of metal ions and cooperative interactions would be expected for the poly(SEAPt and poly(SPDAP~Eu’+ complexes. However, the relative intensity of Eu” ion with (1”) and without polymer (lo), &/lo, were 2.6 and 2.4 for poly(SPDAP)-and poly(SEAP) --ELI)+complexes, respectively. These values are rather lower than those of the monomer system, I,/& = 3.4 for the SPDAP-Eu3+ complex and I,/ZO = 2.9 for the SEAP-Eu’+ complex. The decrease in 1,/I” for the polymer-Et?+ complex might be due to the limitation of the formation of the 2: 1 monomer-Eu3+ complex, caused by the bulkiness of pendant groups. In agreement with this argument, the complexes of Et?+ ions with poly(MMA-co-SPDAP) with 25 mol% of SPDAP units, which could yield a favorable space for the formation of complexes, showed the fluorescence intensities (I”/& = 3.1) comparable to those of the monomer system. However, a significant increase in fluorescence intensity and stability of the complex by “polymer effects” was not observed. The ‘H NMR spectra of complexes showed some notable features. The bond angles of

-HN-P-NHand -O--P-Oin organophosphazenes are known to be in the range 93-106 [20,21], suggesting that these arms attached to P atoms diverged up and down from the almost planar phosphazene ring. As shown in Fig. 8, methylene protons assignable to CH$XfCHresonated at 1.48-I .62 and 1.62-l .78 ppm with integral intensities of four and six protons, respectively. This suggests that protons of two -NH(CH&N(CH& chains in close proximity to the vinylphenoxy moiety are magnetically nonequivalent from those of three alkyldiamino chains, i.e. the vinylphenoxy group significantly affects the chemical shifts of methylene and dimethylamino protons on the same side. In addition, methylene protons (H”) assigned to --CH*NH-P, were observed at 2.96-3.07 ppm with an integral intensity of 2 and other protons, NH-C&-attached to P., and P6 atoms resonated at 2.6c2.71 and 2.83-2.95 ppm with integral intensity of 4. When Eu3+ ions were added to SPDAP ([Eu)+]/[SPDAP] = 2), all protons in the side arms except -C&NHPI shifted to lower fields and a large downfield shift was observed for the signals of -CH,N(CH,),, suggesting that Eu’+ ions bind preferentially to the dimethylamino group. Such downfield shifts might be a result of a contact and

CH,J N CH,' CHzh CH2

CH2; CH2’ c

CH;C

N

I

N

K”,),”

WM2’

4 e

I.,

ppm

I,

.,

,

3.0

2.5

I,

Y 1

,

C

,

2.0

WI,,

I

,

,,

1s

Fig. 8. ‘H NMR spectra of the SPDAP-Eu’+ complex. [Eu’+]/[SPDAP];(a) 0.5; (b) 0.2; (c) without Eu3+ ions.

847

Polystyrenes with pendant aminophosphazenes REFERENCES

Cll=CH~ Fig. 9. Schematic

representation complex.

of the SPDAP-Eu’+

pseudocontact interaction with metal ions. Taking into considerations the behavior of chemical shifts of protons in side arms and the formation of a

2:l SPDAP-Eu3+ complex, it seems reasonable to assume that Et?+ ions are not encapsulated into the space formed by three side arms on the phosphazene ring but sandwiched by two monomers as shown in Fig. 9. Thus, SPDAP and SEAP with ring-opening polyamine could form a complex with Eu’+ ions, although the complex decomposes within several hours. The degree of enhancement of fluorescence intensity was small, indicating that complexes are liable to loss of excitation energy due to intramolecular vibration. In summary, styrene derivatives with polyamine on the cyclophosphazene undergo a facile polymerization that is primarily affected by the degree of hydrogen bond interactions between side arms and solvents. SPDAP and SEAP carrying a dimethylamino group form a 2:l monomer:Eu3+ sandwich complex, and the fluorescence intensity of Eu3+ increased, although the complex decomposed slowly.

1. Allcock, H. R., Klingenberg, E. H. and Welker, M. F., Macromolecules, 1993, 26, 5512. 2. Allcock, H. R., Pucher, S. R. and Scopelianos, A. G., Macromolecules, 1994, 27, 1071. 3. Inoue, K., Nakahara, H. and Tanigaki, T., J. Polym. Sci. Polym. Chem. Eds., 1993, 31, 61. 4. Inoue, K., Kaneyuki, S. and Tanigaki, T., J. Polym. Sci. Polym. Chem. Eds., 1992, 30, 147. 5. Inoue, K., Nishikawa, Y. and Tanigaki, T., J. Am. Chem. Sot., 1991 113, 7609. 6. Okamoto, Y., Ueba, Y., Dzhanibekov, N. F. and Banks, E. Macromolecules, 1981, 14, 17. 7. Yoshino, M., Paoletti, S., Kido, J. and Okamoto, Y., Macromolecules, 1985, 18, 1513. 8. Li, W., Mishima, T., Adachi, G. and Shiokawa, J., Inorganica Chim. Acta, 1987, 131, 287.

9. Nishide, H., Izushi, T., Yoshioka, N. and Tsuchida, E., Polymer Bull., 1985, 14, 387. 10. Alpha, B., Lehn, J.-M. and Mathis, G., Angew. Chem., 1987, 99, 259. 11. Lehn, J.-M. and de Vains, J.-B. R., Helu. Chim. Acfa, 1992, 75, 1221.

12. Mukkala, V.-M. and Kankare, J. J., He/u. Chim. Acta, 1992, 75 1578.

13. Alpoim, M. C., Urbano, A. M., Geraldes, C. F. G. C. and Peters, J. A., J. Chem. Sot. Dalton Trans., 1992, 463.

14. Balzani, V., Berghmans, E., Lehn, J.-M., Sabbatini, N., Terbrde, R. and Ziessel, R., Helu. Chim. Acta, 1990,73, 2083.

15. Wang, Z., Choppin, G. R., Bemardo, P. D., Zanonato, P.-L., Portanova, R. and Tolazzi, M. J. Chem. Sot. Dalton Trans., 1993, 2791.

16. Forsberg, J. H., Coord. Chem. Rev., 1973, 10, 195. 17. Capentier, L. J. and Moeller, T., J. Inorg. Nucl. Chem., 1970, 32, 3575. 18. Kamlet, M. J. and Taft, R. W., J. Chem. SOL.. Perkin II, 1978, 337.

19. Scott, G. E. and Senogles, E., J. Macromol. Sri. Reo. Macromol. Chem.,l973, C(9), 49. 20. Allcock. H. R.. Chem. Rev.. 1972. 72. 317. 21. Marsh, W. C. and Trotter, J., J. khei. Sot.(A), 1971, 169.