close

Вход

Забыли?

вход по аккаунту

?

The differential refractive index increments of statistical styreneacrylonitrilemethyl methacrylate terpolymers.

код для вставкиСкачать
Die Angewandte Makromolekulare Chernie 25 (1972) 163-169 ( N r . 363)
From the Showa College of Pharmaceutical Sciences, Tsurumaki, Setagaya,
Tokyo, Japan
The Differential Refractive Index Increments
of Statistical Styrene/Acrylonitrile/Methyl
Methacrylate Terpolymers
By YUKOKAMBEand CHIKAKOHONDA
(Eingegangen am 2. Miirz 1972)
SUMMARY:
The differential refractive index increment was measured for statistical styrene/
acrylonitrile/methyl methacrylate terpolymers of eight different compositions in
dimethylformamide and in butanone. With the terpolymer compositiop obtained
from infrared absorption and the differential refractive index increments of the
homopolymers, the differential refractive index increments of terpolymers are
calculated. The partial azeotropic terpolymer gives a constant value in the course
of terpolymerization. The differential refractive index increment of a terpolymer
synthesized from other monomer feed than the azeotropic composition changes
with conversion.
ZUSAMMENFASSUNG :
Das Brechungsindexinkrement von acht verschieden zusammengesetzten Terpolymeren aus Styrol, Acrylnitril und Methylmethacrylat wurde in Dimethylfcirmamid und in Butanon bestimmt Aus der infrarotspektroskopisch ermittelten
Zusammensetzung der Copolymeren und den Brechungsinkrementen der Homopolymeren wurden die Brechungsinkremente der Terpolymeren berechnet. Das
ptrrtielle azeotrope Terpolymere besitzt ein konstantes Brechungsinkrement wiihrend der Terpolymerisation, wiihrend die aus anderen Monomermischungen erhaltenen Werte sich mit dem Umsatz iindern.
.
1. Introduction
The differential refractive index increment of a multi-component copolymer
is calculated from the differential refractive index increments of the parent
homopolymers and the composition of the copolymerl, unless intramolecular
interactions between the constituent components or selective adsorption of a
solvent by one of the copolymer components exist. The dependence of differ-
163
Y . KAMBE
and CH. HONDA
ential refractive index increments on the copolymer composition was reported
for some binary copolymersl-7, and a terpolymers. The additivity of the
refractive index increment is established in these experiments. In this paper
the differential refractive index increments of random styrene (S)/acrylonitrile(AN)/methyl methacrylate ( M U )terpolymers are measured and discussed.
2. Experinzentals
2.1 Materials
The monomer mixture shown in Table 1 was diluted with the same volume of
dimethylformamide (DMF). Terpolymerization was carried out at 60"C under
nitrogen atmosphere, a,@'-azobisisobutyronitrile was used as an initiator. Conversion was determined by precipitation with methanol. Fractional precipitation
of terpolymers was carried out for 5 wt.-% solutions in butanone with methanol as
nonsolvent. The volume fraction, y , of nonsolvent in solvent mixture a t the preci-
AN
S
Fig. 1
164
MMA
The composition (weight fraction) of statistical styrene/~rylonitrile/
methyl methacrylate terpolymers (0)
calculated from the analytical IR
data and monomer feed (0).
partial azeotrope having a constant MMA/S in monomer and
terpolymer,
partial azeotrope having a constant A N / S in monomer and terpolymer.
Styrene/Acrylonitrile/Methyl Methacrylate Terpolymers
Tab. 1.
The composition (weight fraction) of statistical styrene/acrylonitrile/
methyl methacrylate terpolymers calculated from the analytical IR data
and monomer mixtures.
Monomer Mixture
Terpolymer
S
T1
T2
T3
0.458
0.745
0.266
0.295
0.644
0.291
0.626
0.682
T4
T5
T6
T7
T8
AN
MMA
S
AN
MMA
0.221
0.208
0.135
0.394
0.146
0.258
0.090
0.114
0.321
0.046
0.599
0.31 1
0.210
0.451
0.285
0.204
0.343
0.758
0.198
0.225
0.610
0.201
0.601
0.693
0.303
0.185
0.173
0.540
0.177
0.368
0.084
0.114
0.354
0.057
0.629
0.235
0.213
0.430
0.315
0.193
pitation point was determined by titration at constant temperature. The details
of terpolymerization and fractionation are reported previouslyo.
2.2 Composition of th terpolymer
I R absorption of the terpolymer film was measured using a Hitachi-215 Spectrometer. The absorption maxima at 2260, 1 730 and 1603 om-' are assigned to AN,
MMA and S components, respectively. According to the HAM'S concept of the
partial azeotrope'o, the mole ratios A N / S of T 7 and MMA/S of T 8 in terpolymer
are equal to the monomer feed ratios. The composition of terpolymers was calculated from I R data based on this idea. A typical IR-spectrum is shown in Fig. 2.
2.3 Di#erential refractive index increment
Differential refractive index increments are measured using a Shimazu Differential Refractometer Type DR-3 with a light of 436 and 546 mp at 20°C. Butanone
and DMF are used as solvents.
3 . Results and Discussion
The terpolymer compositions (weight fraction) obtained from the analytical
IR data are shown in Fig. 1 and in Table 1. With the weight fraction, xi, of
the i-component in a multi-component copolymer and the differential refractive index increment v i of the homopolymer i, the differential refractive index
increment v of a multi-component copolymer is expressed as :
v =- p i
i
xi
where
*xi
= 1.
i
165
Y. KAMBE
and CH. HONDA
Refractive index increments measured and calculated are shown in Table 2.
The observed values of polystyrene and polyrnethyl methacrylate are smaller
100
?
5
6
I
I
40 -
20MMA ,
O2;Oo
2doo d o 0 Id00
Wave number ( c m 9
Fig. 2.
Infrared spectrum of T5, F-8.
Tab. 2.
The differential refractive index increment (em3 g-1) of statistical styrene/acrylonitrile/methyl methacrylate terpolymers and the homopolymers measured a t 20°C and calculated by eq. (1).
I
T1
T2
T3
T4
T5
T6
T7
T8
PS
PAN
PMMA
I
butanone
436 mp
vobs.
Vcalc.
0.160
0.199
0.141
0.152
0.187
0.146
0.181
0.185
0.225
0.136*
0.110
0.169
0.201
0.144
0.154
0.188
0.150
0.185
0.191
DMF
546 mp
VObS.
0.153
0.189
0.137
0.145
0.177
0.140
0.171
0.176
0.207
0.136*
0.108
436 mp
VCSlC.
vobs.
Vpalc.
vobs.
VcaIc.
0.160
0.188
0.138
0.148
0.176
0.144
0.173
0.179
0.089
0.143
0.090
0.102
0.134
0.090
0.124
0.130
0.168
0.085
0.058
0.114
0.146
0.091
0.101
0.133
0.097
0.129
0.136
0.085
0.134
0.086
0.097
0.128
0.088
0.117
0.125
0.158
0.084
0.060
0.110
0.138
0.089
0.098
0.127
0.095
0.124
0.130
* calculated from GLADSTONE-DALE'S
equation
166
546 mp
StyrenelAcrylonitrilelMethyl Methacrylate Terpolymers
about 2 % than those reported by IML~cHTLE~. The observed values of terpolymers coincide with the calculated values from eq. (1) both in butanone and
in DMF.
The composition of the product polymerized from other monomer feed ratio
than the azeotropic composition varies with conversion. The instantaneous
composition of terpolymer is calculated according t o the equation given by
ALFREY
and GOLDFINOER~~,
and the relationship between the instantaneous
compositions of monomer and polymer with conversion is calculated by SKEIST’S
methodl2. But, the composition obtained experimentally is the average value
from the initial terpolymer composition to that a t a definite conversion, not
the instantaneous composition. Instantaneous compositions (mole fraction) of
AN
A
MMA
S
Fig. 3. Instantaneous compositions (mole fraction) of monomer and terpolymer
in the course of terpolymerization for T4.
the initial monomer composition,
A the composition of the unfractionated terpolymer obtained at 68.6
wt.-% conversion,
partial azeotrope having a constant MMA/S in monomer and
terpolymer,
azeotrope having a constant A N I S in monomer and terpolymer,
showing the direction of the composition variation with conversion.
.........__
partial
--
167
Y . KAMBEand CH. HONDA
monomer and polymer in the course of terpolymerization for T 4 are calculated by
SKEIST’S
method and shown in Fig. 3. The unfractionated sample of T 4
obtained a t 68.6 wt.-% conversion shows the average composition. The relative variation in the average composition of the product with conversion is
checked by measuring the differential refractive index increments. Fig. 4
I
1.20%
Butonone
A- 436 my
c dg+
0.2 0
I
I
I
I
I
I
shows the dependence of refractive index increment of the terpolymer product
on conversion. Refractive index increments of T 4 decrease with conversion.
Then, terpolymer T 4 has the composition distribution. The partial azeotropic
terpolymers T 7 and T 8 indicate the respective constant refractive index
increments independent of conversion. I n the case of azeotropic copolymers,
the composition of monomer and polymer does not change in the course of
terpolymerization. Therefore, the product has not the composition distribution.
1
2
W. MLCHTLEand H. FISCHER,
Angew. makromol. Chem. 7 (1969) 147.
H. &MBE, I. MITA, and Y. SHIMURA,Rept. Aeronaut. Res. Inst., Univ. Tokyo
1964, S. 381.
168
Styrene/Acrylonitrile/Methyl Methacrylate Terpolymers
Y. SHIMURA,
Bull. Chem. SOC.Japan 40 (1967) 273.
V. A. MYAGCHENKOV,
A. K. VAGAPOVA,
and E. V. KUZNETSOV,
Vysokomol.
Soedin B 11 (1969) 673.
ij J. VELI~KOVIC
and J. VUKAJLOVI~-FILIPOVIC,
Angew. mekromol. Chem.
13 (1970) 79.
(3 D. BRAUN,D. CHAUDHARI,
and W. MACHTLE,Angew. makromol. Chem. 15
(1971) 83.
D. BRAUNand G. MOTT,Angew. makromol. Chem. 18 (1971) 183.
W. MACHTLE,Angew. makromol. Chem. 15 (1971) 17.
c' Y. KAMBE,
J. Macromol. Sci.-Chem., to be published.
10 G. E. HAM,J. Macromol. Chem. 1 (1966) 93.
1
' T. ALFREYand G. GOLDFINGER,
J. chem. Physics 12 (1944) 322.
1% I. SKEIST,J. Amer. Chem. SOC.68 (1946) 1781.
3
*
169
Документ
Категория
Без категории
Просмотров
1
Размер файла
249 Кб
Теги
styreneacrylonitrilemethyl, increment, methacrylate, statistics, differential, index, refractive, terpolymer
1/--страниц
Пожаловаться на содержимое документа