- Email: [email protected]
Methods of crosslinking unsaturated carborane-containing polymers and a study of the properties of their copolymers
Methods of erosslinking unsaturated carborane-containing polymers
1143
16. J. FURUKAVA and T. SAEGUSA, Polimerizatsiya al'degidov i okisei (Polymerization of Aldehydes and Oxides). p. 198, Mir, 1965 17. Ya. I. URBONAVICHENYE, Avtoref. dis. na soiskaniye uch. st. kand. Khim. nauk (Thesis I)iscussion, Canditate in Chemical Science). p. 23, Polytech. in-t, Kaunas, 1979 18. Yu. A. GRAZHULYAVIL~YUS, Avtoref. dis na soiskaniye uch. st. kand. Khim. nauk (Thesis I)iscussion, Canditate in Chemical Science). p. 23, Polyteeh. in-t, Kaunas, 1980 19. I. V. KOZLOV and G. I. BRAGINSKII, Khimiya i tekhnologiya polimernykh plenok (The Chemistry and Technology of Polymer Films). p. 174, Iskusstvo, 1965
Polymer Science U.S.S.R. Vol. 25, No. 5, pp. 1143-1152, 1983 Printed in Poland
0032-3950/83 $10.00 + . 0 0 1984 P e r g a m o n Press L t d .
METHODS OF CROSSLINKING UNSATURATED CARBORANE-CONTAINING POLYMERS AND A STUDY OF THE PROPERTIES OF THEIR COPOLYMERS* V. V. KORSHAK, :N. I. BEKASOVA,A. I. SOLOMATINA,ZH. P. VAGINA, N. V. KLr~ENTOVX and A. P. SUPRU~ A. 1~. Nesmeyanov Institute for Elemento-Organic Compounds, U.S.S.R. Academy of Sciences (Received 30 Nowmber 1981)
The influence of the structure of unsaturated organoborane (carborane)-containhlg polyesters on their reactivity towards copolymerization with vinyl compounds in solution, in the presence of radical and ionic catalysts, in emulsion with radical-type catalysts, in bulk using a thermochemical method and under y-irradiation at high pressure, has been examined. Certain properties of the resulting copolymers were studied. I t was found that copolymers based on the above polyesters are characterized by higher stability towards thermal oxidation and higher adhesional parameters than analogous copolymers without organoborane units. UI~SATURATED p o l y e s t e r s t r u c t u r e s were p r e p a r e d earlier on [1] w i t h t h e following s t r u c t u r e s w i t h o r g a n o b o r a n e u n i t s in t h e acid c o m p o n e n t : h o m o g e n e o u s [ - OCHICH---- CHCH:OOCCBl~:IIoCCO --]~ [--OCH:C-- CCHIOOCCBI~-I10CCO--]. I a n d m i x e d o r g a n o b o r a n e - p o l y e s t e r s , differing f r o m e a c h other, according t o * Vysokomol. soyed. A25: No. 5, 989-996, 1983.
1144
V.V.
KORSHA~ et al.
t h e method of preparation:
[--0--R--OOCCBloHloCCOO--R--OOCCH=CHCO--]n II {[- 0 - R - OOCCH~ CHCO]~-- O -- R -- OOCCB10H10CCO-- }n, III whore 1%= -- (CH2)2--, -- (CHs)4--, -- (CH2),--, -- (C~I:[~)~O--, b= 3-36. The number of unsaturated residues in the basic unit of those polyesters, present on a single carborane nucleus, varied from 1 to. 36, which corresponded to boron contents of 37.9 to 1-1%. The most important property of these unsaturated polyesters, opening-up means of practical application, is their ability to eopolymerize with different vinyl monomers. I n connection with the above, the study of this property presented undoubted interest. The ability to eopolymerize with unsaturated compounds was studied in solution in the presence of radical and ionic catalyst, in emulsion with radical catalysts, in bulk using a thermochemioal method and also under 7-irradiatiou (radiochemical method) and high pressure. The vinyl compounds used were styrene, acrylonitrile and 1, I, 2-trichlorobutadiene- 1,3. The extent of copolymerization was judged from the gel fraction obtauted b y extracting the hardened carborane polyether in a Soxhlet apparatus. Since the radical or ionic copolymerization methods have been the raost studied and are experimentally the simplest they were used here. For the thermochemical set~ing method, in which styrene was used as comonomer, the eopolymeriza~ion of the starting materials (weight ratio l : l ) was carried out in the presence of benzoyl peroxide (2% by weight of starting material mixture) at 80-100 ° b y the method of reference [2]. The results obtained showed (Table 1), that under thermochemical solidification conditions the polyester-m-carborane structure I I I (Table 1, polyetlmrs 4-6), in which the ratio of unsaturated and carborane residues in the basic polyester unit was more than unity, reacts with styrene b u t the polyester-mcarborane structures I and II (polyesters 1-3), with an equimolar ratio of m~ saturated and m-carborane groups in the basic unit, do not copolymerize witl~ styrene. I t may be concluded f r o m these results that the introduction into the cutsaturated polyester chain of the electron-accepting m-carborane nucleus evidently causes a reduction in the reactivity of the unsaturated bonds. Contrary to m-carborane-containing polyesters, all polyesters of n-earboranecarboxylie acid eopolymerize with styrene which evidently m a y be explained b y the weaker electron-accepting properties of ~he n-earborane nucleus, which hardly reflect the reactivity of the unsaturated bonds (see Table 1, polyether8
7-12).
{[--O(CH.).OOCCH=CHCO--]~O(CHs)e OOCCB~,oCCO--)~
I
I I
1.24 26:1
{[--O(C0~I,)IOIOCCH=CHCO]~0(C~,)I0,OCCBIoHIoCCO~],
12
3-35 17:1
([--0(0H,),00COH=CHC0],.0(CH,)o000OBtoHtoCC0--}.
HI
11
13.71
3:1
I
23-56
36.63
37.42
{[--O(CH~)~OOCCH=CHCO]~O(CH,) ~OOCBt~H.oCCO---}.
1:1
1 :1
1:1
11.51 3.82
III
I
[--O(CH,) ,00CCB~eHtoCCOO(CHs),OOCCH=CHC0--].
i
[--OOHIC ~ C C H I 0 0 C C B I ~ , C ~ O - - ] , ,
t
[~OC~sCH----CHC'~,OOCCBzJ:IloCCO~].
I
( [ - - 0 (C~I,) ,O,OCC~ =CT[CO],O (C,H,),0CCB~oH~,CCO--}.
{[---O(CII,),OOCCII=CHCO]~O(CIIz),OOCCB~oH~oCCO--}.
10:1
35.26 21.10 9.75
1:1 1:1 3"1 5:1
[--OC-'~IC mCCH,OOCCB,0H,0CCO~], [~O(CH,) 6OOCCB,oH,oCCOO(CH,) ,OOCCH=CHCO---],
10
III
I
I
H HI HI III
I
l~ot deter-
Not determined Ditto
12.08 3.81
15.60
Ditto
mined
2-60 3-80 l~ot deter.
Ditto
mined
in
37.90
Formula of polyester unit
%
(found),
1:1
Boron content ,
i
i
i
i
i
,
78-5
87.0
60.0 84"6
58.0
78'5 60.0
0 78.5 76.5
0
tent,
con-
Gel ifraction
POLYESTER-~I~- AND n-CARBORANES
[--OCH,CH----CHOH~OOOOB~I~oCC0--].
OF UNSATURATED
gel fraction
WITH STYRENE
FORM~ED D U R I N Q 0 0 P O L ~ Z A . T I O N
in original polyester
0~ GEL FRACTION
l%atio of unsaturated and carborane units
1. C H A I ~ G E I N A l t t o u N T
Polymer Polyester ~o. structure
TABL~
m
0~
5
o
o
O
1146
V.V.
Ko~s~
e~ al.
Neither did we succeed in reacting styrene with 1,1,2-trichlorobutadiene-l,3 with the polyester-m-carborane structure I [ - OCHICH~ CHCHIOOCCB10H10CCO--]~ and structure II [ - O(CH2)eOOCCBloH10CCOO(CH2)eOOCCH----CHCO--]~ in benzene or methylene chloride solution in presence of boron trifluoride ethcrate, benzoyl peroxide, tert-butyl peroxide and dicyclohexyl peroxy carbonate. During the copolymerization of the unsaturated polyester-m-carborane structure II [ - O(CH,),OOCCB,oHIoCCO0(CH2)eOOCCH = CHCO--]~
in emulsionin the presence of benzoy] peroxide, tert-bui~ylperoxide and dieyclohexyl peroxy carbonate, the yield of gel fraction is altogether only 7%. It is known that high pressures, estimated at thousands of atmospheres, cause acceleration of polymerization [3]. Besides this, are also encountered polymerization processes which only occur at high pressures [4]. I t is also known that unsaturated polyesters are capable of copolymerizing by the action of y-radiation, which was first demonstrated in reference [5] and at present is widely used in practice [2, 5-7]. These methods of copolymerization were expediently applied first to the polyester structures I and II, which are not copolymerized with vinyl monomers by the above-mentioned methods i.e. to polyesters with a large boron content. The eopolymerization of unsaturated ~n-carborane-contai~ing polyesters with styrene and acrylonitrile under high pressure was studied for the case of polyester-m-carboranes of structure I at 80, 120 and 160° in the pressure or absence of initiators. In copolymerization with styrene approximately the same weight ratio of starting materials was used as in thermochemical setting: in the case of acrylonitrile, the ratio of starting materials which ensured a homogeneous system was taken. The results obtained are given in Table 2. As the data of Table 2 indicate, polyester-m-carborane with three bonds in the basic polyester chain does not eopolymerize with styrene (experiments 5 and 6) under 1000 MPa pressure. Unsaturated m-carborane-eont~duing polyesters with 2 !lugs in the basic polyester chain in the given conditions copolymerize with styrene and acrylonitrile both with and without an initiator, with gel fraction yields of 35 to 54~. It should be noted that copolymerization proceeds easier with styrene than with aerylonitrile. I n the application of high pressure for copolymerizing unsaturated polyester-m-earboranes (experiments 7-10), which are capable of being solidified by the thermochemieal method, it was shown that in this case, eopolymerization proceeds both in the presence and in the absence of an initiator. Moreover, the yield of gel fraction is almost the same as under conditions of thermochemical setting.
Methods of erossllnking unsaturaf~d carborane-containing polymers
1147
In radiational setting, polyesters of structures I and II, admixed with styrene (1 : 1 weight ratio) in evacuated, sealed ampoules, were subjected to y-irradiation from Coe° isotope (dose of 10, 20 and 80 Mrads, at 20 and 80°). It was found that the unsaturated m-carborane-containing polyesters undergo copolymerization with styrene, under the influence of ?-radiation and moreover, the optimum dose, corresponding to a maximum gel fraction yield of 70-78%, is 20 Mrads (see Figure), as in the case of radiation setting of oligoestermaleates [7]. A change in irradiation temperature is not reflected in the gel fra~ion yield. 80
qo I
I
I
I
40
I
80
Bose, Head Relation of a m o u n t of gel fraction to irradiation dose for polyesters of the structure:
[-- OCHICH~CHCH~OOCCB1,Hx0CCO--]n(1) and [--O(CHI)6OOCCBlal~loCCOO(CH~)6•OOCCH=OHCO--],, (2). Comparative studies of the thermal stability of unsaturated polyestercarborane-styrene and -acryloni~rile copolymers indicated that the former has a higher stability than the latter (the temperatures for a 5 ~ weight loss in air are 300400 ° and 250-280 ° respectively) hence the former copolymer was studied in more detail. It was shown that changes of boron content in the range 3-16~o had no appreciable effect on thermal stability, which in most cases exceeded t h a t of the polyestercarborane starting materials [1]. According to published data [8-10], the thermal degradation of polyestermaleate-s~rene copolymers begins at lower temperatures than that of the polyestermaleates, which the authors of the above articles explain in the first place by rupturing of the C--C bonds between the main polyester chain and the crosstinking agent. The higher thermal stability of the solidified unsaturated polyester carboranes in comparison with the unsolidified ones may apparently be explained by the ability of the carborane groupings to stabilize homolytic cleavage of the polymers [11]. A study of the chemical stability of the styrene copolymers of unsaturated polyestercarboranes, estimated from the weight loss of the samples after keeping them in 3 0 ~ sulphuric and nitric acids for 3 days, showed that they are degraded under these conditions (0.2-8.0~/o weight loss). Unsaturated polyestercarboranes, solidified by irradiation, have the best chemical stability.
nomer
1:1.5
1:1 1:2 1:1.5
Styrene Styrene Styrene
8
9
10
Polymer of structure I I
Styrene
Acrylonitrile 4 - 0 : 1 1:1.5 Styrene
1:1.6 Styrene Acrylonitrile 4 - 5 : 1
Polymer of structure I 1 : 1.33 Styrene
Monomer
1:1
{[--O(CHs) a 0 0 C C H = C H C 0 ] ~ " - - 0 (CHI).OOCCBIoHIoCCO}.
[--OCHIC -- CCHIOOCCBIoH10CCO---],
[--0CH2CH=CHCH~00CCBIoHI.CC0--].
Formula of polyester unit
Weight ratio polyester : m o -
Styrene
No.
peri. ment
][~x-
Benzoyl peroxide Tert -butyl peroxide (1) Tert-butyl peroxide (1) No initiator
Benzoyl peroxide (1.0) No initiator Tert -butyl peroxide (0.5) No initiator Benzoyl peroxide Dicyelohexylperoxycarbohate
Initiator, wt. %
160 80-100 52.0 0 24"45
80 120 120 160
75.0 90.0 85.0 76-0
14.56 9.19 16.40 9-96
50
120 160 48"5 35.0 8.22 27.33
80
Solidification temperature, °C
54.0
Gel fraction yield, %
12.28
%
content in eopolyreeF,
Boron
STYRENE AND ACRYLONXTRILE UNDER 1 0 0 0 M P a oN THE GEL FRACTION YIELD
TABLE 2. EFFECT OF PROCESS CONDITIONS IN TJ:l.lg OOPOLY3fERIZA.TION OF UI~SATU~gATED m-CARBORANE-CONTAINING POLYESTERS WITH
g
0o
Methods of crosslinking unsaturated carborane-containing polymers
1149
Thermal stability, resilience, i m p a c t strength and density were evaluated for the styrene-polyester-m-carboranes of structure I I I . I t was found t h a t as t h e boron content increased, the i m p a c t strength was decreased, resilience increased a n d density a n d t h e r m a l stability were practically u n c h a n g e d (see Table 3). .An evaluation of the quantitative effect of boron content in the copolymers on their adhesion properties was carried out on polyester-m- a n d polyester-ncarboranes of structure I I I b y means of comparative tests on the shear of a l u m i n i u m plates, glued with styrene solutions of the u n s a t u r a t e d polyester carboranes a n d of the analogous polyestermaleates containing no carborane groupings. TABLE 3.
~PHYsICOI~ECHANICA_L
CHARA.CTERISTICS
TURATED
POLYESTER
OF
THE
STYRENE
COPOLY~ERS
OF
UNSA-
-m -CARB ORANE
( -- [O (CH,) ,OOCCH----CHCOJkO (CH~)~OOCCB~0H~0CCO}~ Content of polyester in copoly~ner,
%
Thermal stability, °C
Resilience, kg/cm2
Hardness (Brinel), MPa
Density at 20°, g/cm a
Elastic modulus E × 10-a, MPa
1.7 1.3
1.3 1.7
1.18 1.I3
1.57 1.00
i
28 13
140 I40
t 1
The results are presented in Table 4. As Table 4 shows, the shear resistance of a glued joint, in t h e case of m-carborane-containing copolymers, exceeds b y 50°/o a n d more the same characteristic of the analogous polyestermaieate (earborane group absent). A change of boron content in the original polyether has practically no effect on t h e joint durability. During the tests on samples glued b y styrene solutions of n-carboranecontaining u n s a t u r a t e d polyesters (Table 4, polyesters 3 and 9), it was found t h a t modified m-carborane dicarboxylic acid only improved the adhesion properties of the u n s a t u r a t e d polyethers slightly.
Startiny ma~,rial~. Unsaturated m- and n-carborane-containing polyesters were synthesized by the method of reference [1]. Chromatographically pure carborane dicarboxylic dichloranhydrides were used in the latter. Table 5 gives some of the properties of the polyestercarboranes prepared. 1,1,2-Trichlorobutadiene-l,3 was synthesized and purified by the method in reference [12], stored in sealed ampoules at dry ice or liquid nitrogen temperature. It was distilled under nitrogen, in vacuum (b.p.~32°/665 Pa, n~=1.5345, d-~ 1.37 g/cma; the literature [12] gives b.p.----32°/665 Pa, n~----1.5350) before use. Styrene was purified by a known method [13]. After twice distilling over a molecular sieve, in a current of argon, it had a b.p. of 145.2°, n ~ = 1.5468, d--~0.906 g/cma. Aerylonitrile was also purified as in reference [13] and distilled under argon (b.p.--~77.3°, n~=1.3910, d~0-8060; according to reference [13], b.p.----77.3°, n ~ 1.3911, d=0-8060 g/cma). Copolymerization of un~2turated polyesteroarboranes. A batch of polyestercarborane and styrene was stirred for 5-10 rain at 50-60 °. The styrene solution obtained was poured into
0
8
5 6 7
4
3
I~To.
ITler,
Poly-
{[_O(C~I,O),--OCCH=CHC0]~--O(CaH,O),--OCCB,~I{,oCCO--}s
I
{[--OCCH-~CHCOO(CH,)60]r--O(CH2)eOOCCBloHIoCCO--)* {[--OCCH ~--CHCOO(CH,) 60--],O (CH,) 6OOCCB loH~oCG0--}{[--0CCH~CHCOO(CH,)60]r-O(CH,) ,OOCCB,oHxoCC0--}* [--O(CsH,O)I--0CCH=CHCO--], {[--O(C~I,O) m---OCOH= CHC0]r--O(C,H40),--0CCB,oH,0CC0--),
I
[--OCCH=CHCO--O(GHI) e--]{[--OCCH~-CHCOO(CH,),O]r-O(CH,),OOCCB,oH,oCOO--}.
Polyester starting material
12"03
4600 4000
0"sllec,r
6.0 7-9 9"2 4.0 6.5 6.8 4*9
4"4 1 "24 7-32 3700
4.5 8"8
at 25 °, MPa
6030 3800 8000 4000 2470 6000
11-67 8"9 3"6
Boron con(%) in original polyesters tent
Molecular weight from terminal groups
TABLE 4. ST~NOTH OF ADHESIONOF ALUMINIU~IPLATES (Polyester : styrene weight ratio---- 1.0 : 1-0, glass transition temperature 80 °, holding time 6 hr)
Methods of erosslinking unsaturated earborane-containing polymers
1151
test tubes, 2% of benzoyl peroxide (on weight of original mixture) added and heated in an inert gas atmosphere at 80-100 a for 8-10 hr the copolymerization conditions are given in Table 1. The copolymerization of the unsaturated polyester carboranes with styrene and acrylonitrile under pressure was carried in Teflon ampoules at 80, 120 and 160° at 1000 MPa. The conditions are shown in Table 2. The irradiation of unsaturated polyestercarboranes was carried out in glass ampoulcs in equipment for radiation studies, with Co6°, with doses ferrosulphatc dosimeter. JMethod of s~udying the polyestercarborane~. The mean MWs were determined from she acid and hydroxyl numbers by the method of reference [14]. TABLE 5. POLYESTERCARBORANE STARTING MATERIALS
Polymer structure
Boron content,
I II III
35.19-37.90 18.41-29.00 1.12-11-57
%
Molecular weighs (from end groups)
Temperature for 5~o weight loss in air, °C
Ratio of unsaturated and carborane units
2600-4088 1770-3620 2400-9900
150-275 250-275 180-380
1:1 1:1 36:1
A 1-2 g batch of pulverized copolymer was placed in a tube with 30~o nitric or sulphurie acid, brought to boiling and then kept at 20-22 ° for 3 days. Then the oopolymer was filtered off, washed with water and extracted in a Soxlet for 18 hr to free it from low molecular weight products, after which it was dried in vacuum and weighed. Thermogravimetric studies of the polyestercarboranes and their copolymers were carried out at the polymers laboratory of the INEOS of the U.S.S.R. Academy of Sciences, on a derivatograph (rate of temperature rise, 4.5°/rain). The physicomechanical parameters of the test samples of solidified polyestercarboranes were determined as follows: thermal stability on a "Plastometer" apparatus at a load~lg of 10 MPa and increasing temperature: resilience on the "Dinostat"; Brincl hardness on a TP-1 apparatus, at 2.5 MPa loading; copolymer densities were determined in isopropanol; the limit of glued joint strength under shear by GOST 9147-65.
The a u t h o r s express their t h a n k s tx) V. M. Zhalin a n d A. A. sion a n d help in c a r r y i n g o u t e x p e r i m e n t s u n d e r pressure a n d for discussions a n d assistance in c a r r y i n g o u t e x p e r i m e n t s using m e t h o d of solidification. Tran~/ated
Z h a r o v for discusalso B. L. T s e t h n the radiochemical by C. W. C ~ e
REFERENCES 1. A. I. 80LOMATINA, N. I. BEKASOVA, V. V. KOR8HAK, Zh. P. VAGINA and A. V. D'YACHI~_NK0, Plast. massy, 9, 13, 1976 2. 8. L 01WEL'CHENXO, Slozhnye oligoefiry i polirnery na ikh osnove (Oligoesters and Polymers Based on Them). l~aukova duml~, Kiev, 1976 3. V. V. KORSHAK, A. M. POLYAKOVA and M.D. SUCHK0VA, Izv. Akad. Nauk SSSI~, Otd. Khim. n., 1111, 1959
1152
V. S. KImOAlCSKII et a/.
4. M. G. GONI~RERG, Khimicheskoye ravnovesiyo i skorost' reaktsii pri vysokikh davl e n i y a k h (Chemical Equilibrium a n d Reaction R a t e a t High Pressures). K h i m i y a , 1959 5. Y. V. SMITS a n d E. I. LOMTON, Science 113: 2947, 1951 6. Kh. S. BAGDASAR'YAN, Teoriya radikalnoi polhnerizatsii (The Theory of Radical Polymerization). Nauka, 1966 7. N. G. VlDENINA, Dis. na soiskaniye uch. st. kand. Khim. n a u k (Disc. on Thesis, Candit a r e in Chemical Science). I.Kh.V.S. Akad. N a u k IYkrSSR, Kiev, 1969 8. O. I. SAVlCHEVA, Dis. na so iskaniye uch. st. kand. khim. n a u k (Disc. on Thesis, Cand i t a t o in Chemical Science). 2qlIPM, 1972 9. E. G. ZIL'BERMAN, Dis. na soiskaniye uch. st. kand. khim. n a u k (Disc. on Thesis, Canditate in Chemical Science). I~IIPM, 1972 10. B. M. KOVARSKAYA, A. S. STRIZHENOVA, N. I. CHIBISOVA, Ye. G. GINTSBERG, E. V. MIKHAILOVA a n d Ye. L. KAGANOVA, Plast. massy, 5, 5, 1965 11. Yu. L. AVETISYAN, P. I. GRIBKOVA, S. A. PAVLOVA, I. A. GRIBOVA a n d V. V. KORSHAK, Vysokomol. soyed. A21: 502, 1979 (Translated in P o l y m e r Sci. U.S.S.R. 21: 3, 550, 1979) 12. T. MATSUDA and T. JUMOTO, Bull. Chem. Soc. J a p a n 40: 8, 1991, 1967 13. Kh. SERENSON and G. KEMPBEL, Preparativniye m e t o d y khimii polimerov (Preparative Methods of Polymer Chemistry). Mir, 1965 14. V. V. KORSHAK and S. V. VINOGRADOVA, Geterotsepnye poliefiry (Heterochain Polymers). lXlauka, 1968
Polymer Science U.S.S.:R.Vol. 25, 1~'o.5, pp. 1152-1161. 1983 Printed in Poland
THE
0032-3950/83 $10.00+.00 © 1984 Pergamon :Press :Ltd.
SYNTHESIS OF HE~TEROFUNCTIONAL POLYMERS PEROXIDE AND ANHYDRIDE GROUPS*
WITH
V. S. KURGANSKII,V. _A_.PucmN, S. A. VOROl~OVand V. S. TOKAREV Lvov Polyteclmical I n s t i t u t e
(Received 1 Dseember 1981) New heterofunctional polymers were prepared b y copolymerization of 5-tertbutylperoxy-5-methyl-l-hexene-3-yne with maleie anhydride a n d from a mixture of these two with styrene and the features of the process were studied. The synthesis of these polymers was found to obey the rules of inhibited polynlerization as a result of active participation of peroxidic monomer in the chain transfer and termination. For the first time an equation was derived for the rate of terpolymerization in the presence of peroxide monomer which satisfactorily describes the process, over a wide concentration range. F r o m this equation, the integral and differential compositions o f b i n a r y a n d t e r t i a r y anhydride-containing polyperoxides were calculated. * Vysokomol. soyed. A25: No. 5, 997-1004, 1983.
1143
16. J. FURUKAVA and T. SAEGUSA, Polimerizatsiya al'degidov i okisei (Polymerization of Aldehydes and Oxides). p. 198, Mir, 1965 17. Ya. I. URBONAVICHENYE, Avtoref. dis. na soiskaniye uch. st. kand. Khim. nauk (Thesis I)iscussion, Canditate in Chemical Science). p. 23, Polytech. in-t, Kaunas, 1979 18. Yu. A. GRAZHULYAVIL~YUS, Avtoref. dis na soiskaniye uch. st. kand. Khim. nauk (Thesis I)iscussion, Canditate in Chemical Science). p. 23, Polyteeh. in-t, Kaunas, 1980 19. I. V. KOZLOV and G. I. BRAGINSKII, Khimiya i tekhnologiya polimernykh plenok (The Chemistry and Technology of Polymer Films). p. 174, Iskusstvo, 1965
Polymer Science U.S.S.R. Vol. 25, No. 5, pp. 1143-1152, 1983 Printed in Poland
0032-3950/83 $10.00 + . 0 0 1984 P e r g a m o n Press L t d .
METHODS OF CROSSLINKING UNSATURATED CARBORANE-CONTAINING POLYMERS AND A STUDY OF THE PROPERTIES OF THEIR COPOLYMERS* V. V. KORSHAK, :N. I. BEKASOVA,A. I. SOLOMATINA,ZH. P. VAGINA, N. V. KLr~ENTOVX and A. P. SUPRU~ A. 1~. Nesmeyanov Institute for Elemento-Organic Compounds, U.S.S.R. Academy of Sciences (Received 30 Nowmber 1981)
The influence of the structure of unsaturated organoborane (carborane)-containhlg polyesters on their reactivity towards copolymerization with vinyl compounds in solution, in the presence of radical and ionic catalysts, in emulsion with radical-type catalysts, in bulk using a thermochemical method and under y-irradiation at high pressure, has been examined. Certain properties of the resulting copolymers were studied. I t was found that copolymers based on the above polyesters are characterized by higher stability towards thermal oxidation and higher adhesional parameters than analogous copolymers without organoborane units. UI~SATURATED p o l y e s t e r s t r u c t u r e s were p r e p a r e d earlier on [1] w i t h t h e following s t r u c t u r e s w i t h o r g a n o b o r a n e u n i t s in t h e acid c o m p o n e n t : h o m o g e n e o u s [ - OCHICH---- CHCH:OOCCBl~:IIoCCO --]~ [--OCH:C-- CCHIOOCCBI~-I10CCO--]. I a n d m i x e d o r g a n o b o r a n e - p o l y e s t e r s , differing f r o m e a c h other, according t o * Vysokomol. soyed. A25: No. 5, 989-996, 1983.
1144
V.V.
KORSHA~ et al.
t h e method of preparation:
[--0--R--OOCCBloHloCCOO--R--OOCCH=CHCO--]n II {[- 0 - R - OOCCH~ CHCO]~-- O -- R -- OOCCB10H10CCO-- }n, III whore 1%= -- (CH2)2--, -- (CHs)4--, -- (CH2),--, -- (C~I:[~)~O--, b= 3-36. The number of unsaturated residues in the basic unit of those polyesters, present on a single carborane nucleus, varied from 1 to. 36, which corresponded to boron contents of 37.9 to 1-1%. The most important property of these unsaturated polyesters, opening-up means of practical application, is their ability to eopolymerize with different vinyl monomers. I n connection with the above, the study of this property presented undoubted interest. The ability to eopolymerize with unsaturated compounds was studied in solution in the presence of radical and ionic catalyst, in emulsion with radical catalysts, in bulk using a thermochemioal method and also under 7-irradiatiou (radiochemical method) and high pressure. The vinyl compounds used were styrene, acrylonitrile and 1, I, 2-trichlorobutadiene- 1,3. The extent of copolymerization was judged from the gel fraction obtauted b y extracting the hardened carborane polyether in a Soxhlet apparatus. Since the radical or ionic copolymerization methods have been the raost studied and are experimentally the simplest they were used here. For the thermochemical set~ing method, in which styrene was used as comonomer, the eopolymeriza~ion of the starting materials (weight ratio l : l ) was carried out in the presence of benzoyl peroxide (2% by weight of starting material mixture) at 80-100 ° b y the method of reference [2]. The results obtained showed (Table 1), that under thermochemical solidification conditions the polyester-m-carborane structure I I I (Table 1, polyetlmrs 4-6), in which the ratio of unsaturated and carborane residues in the basic polyester unit was more than unity, reacts with styrene b u t the polyester-mcarborane structures I and II (polyesters 1-3), with an equimolar ratio of m~ saturated and m-carborane groups in the basic unit, do not copolymerize witl~ styrene. I t may be concluded f r o m these results that the introduction into the cutsaturated polyester chain of the electron-accepting m-carborane nucleus evidently causes a reduction in the reactivity of the unsaturated bonds. Contrary to m-carborane-containing polyesters, all polyesters of n-earboranecarboxylie acid eopolymerize with styrene which evidently m a y be explained b y the weaker electron-accepting properties of ~he n-earborane nucleus, which hardly reflect the reactivity of the unsaturated bonds (see Table 1, polyether8
7-12).
{[--O(CH.).OOCCH=CHCO--]~O(CHs)e OOCCB~,oCCO--)~
I
I I
1.24 26:1
{[--O(C0~I,)IOIOCCH=CHCO]~0(C~,)I0,OCCBIoHIoCCO~],
12
3-35 17:1
([--0(0H,),00COH=CHC0],.0(CH,)o000OBtoHtoCC0--}.
HI
11
13.71
3:1
I
23-56
36.63
37.42
{[--O(CH~)~OOCCH=CHCO]~O(CH,) ~OOCBt~H.oCCO---}.
1:1
1 :1
1:1
11.51 3.82
III
I
[--O(CH,) ,00CCB~eHtoCCOO(CHs),OOCCH=CHC0--].
i
[--OOHIC ~ C C H I 0 0 C C B I ~ , C ~ O - - ] , ,
t
[~OC~sCH----CHC'~,OOCCBzJ:IloCCO~].
I
( [ - - 0 (C~I,) ,O,OCC~ =CT[CO],O (C,H,),0CCB~oH~,CCO--}.
{[---O(CII,),OOCCII=CHCO]~O(CIIz),OOCCB~oH~oCCO--}.
10:1
35.26 21.10 9.75
1:1 1:1 3"1 5:1
[--OC-'~IC mCCH,OOCCB,0H,0CCO~], [~O(CH,) 6OOCCB,oH,oCCOO(CH,) ,OOCCH=CHCO---],
10
III
I
I
H HI HI III
I
l~ot deter-
Not determined Ditto
12.08 3.81
15.60
Ditto
mined
2-60 3-80 l~ot deter.
Ditto
mined
in
37.90
Formula of polyester unit
%
(found),
1:1
Boron content ,
i
i
i
i
i
,
78-5
87.0
60.0 84"6
58.0
78'5 60.0
0 78.5 76.5
0
tent,
con-
Gel ifraction
POLYESTER-~I~- AND n-CARBORANES
[--OCH,CH----CHOH~OOOOB~I~oCC0--].
OF UNSATURATED
gel fraction
WITH STYRENE
FORM~ED D U R I N Q 0 0 P O L ~ Z A . T I O N
in original polyester
0~ GEL FRACTION
l%atio of unsaturated and carborane units
1. C H A I ~ G E I N A l t t o u N T
Polymer Polyester ~o. structure
TABL~
m
0~
5
o
o
O
1146
V.V.
Ko~s~
e~ al.
Neither did we succeed in reacting styrene with 1,1,2-trichlorobutadiene-l,3 with the polyester-m-carborane structure I [ - OCHICH~ CHCHIOOCCB10H10CCO--]~ and structure II [ - O(CH2)eOOCCBloH10CCOO(CH2)eOOCCH----CHCO--]~ in benzene or methylene chloride solution in presence of boron trifluoride ethcrate, benzoyl peroxide, tert-butyl peroxide and dicyclohexyl peroxy carbonate. During the copolymerization of the unsaturated polyester-m-carborane structure II [ - O(CH,),OOCCB,oHIoCCO0(CH2)eOOCCH = CHCO--]~
in emulsionin the presence of benzoy] peroxide, tert-bui~ylperoxide and dieyclohexyl peroxy carbonate, the yield of gel fraction is altogether only 7%. It is known that high pressures, estimated at thousands of atmospheres, cause acceleration of polymerization [3]. Besides this, are also encountered polymerization processes which only occur at high pressures [4]. I t is also known that unsaturated polyesters are capable of copolymerizing by the action of y-radiation, which was first demonstrated in reference [5] and at present is widely used in practice [2, 5-7]. These methods of copolymerization were expediently applied first to the polyester structures I and II, which are not copolymerized with vinyl monomers by the above-mentioned methods i.e. to polyesters with a large boron content. The eopolymerization of unsaturated ~n-carborane-contai~ing polyesters with styrene and acrylonitrile under high pressure was studied for the case of polyester-m-carboranes of structure I at 80, 120 and 160° in the pressure or absence of initiators. In copolymerization with styrene approximately the same weight ratio of starting materials was used as in thermochemical setting: in the case of acrylonitrile, the ratio of starting materials which ensured a homogeneous system was taken. The results obtained are given in Table 2. As the data of Table 2 indicate, polyester-m-carborane with three bonds in the basic polyester chain does not eopolymerize with styrene (experiments 5 and 6) under 1000 MPa pressure. Unsaturated m-carborane-eont~duing polyesters with 2 !lugs in the basic polyester chain in the given conditions copolymerize with styrene and acrylonitrile both with and without an initiator, with gel fraction yields of 35 to 54~. It should be noted that copolymerization proceeds easier with styrene than with aerylonitrile. I n the application of high pressure for copolymerizing unsaturated polyester-m-earboranes (experiments 7-10), which are capable of being solidified by the thermochemieal method, it was shown that in this case, eopolymerization proceeds both in the presence and in the absence of an initiator. Moreover, the yield of gel fraction is almost the same as under conditions of thermochemical setting.
Methods of erossllnking unsaturaf~d carborane-containing polymers
1147
In radiational setting, polyesters of structures I and II, admixed with styrene (1 : 1 weight ratio) in evacuated, sealed ampoules, were subjected to y-irradiation from Coe° isotope (dose of 10, 20 and 80 Mrads, at 20 and 80°). It was found that the unsaturated m-carborane-containing polyesters undergo copolymerization with styrene, under the influence of ?-radiation and moreover, the optimum dose, corresponding to a maximum gel fraction yield of 70-78%, is 20 Mrads (see Figure), as in the case of radiation setting of oligoestermaleates [7]. A change in irradiation temperature is not reflected in the gel fra~ion yield. 80
qo I
I
I
I
40
I
80
Bose, Head Relation of a m o u n t of gel fraction to irradiation dose for polyesters of the structure:
[-- OCHICH~CHCH~OOCCB1,Hx0CCO--]n(1) and [--O(CHI)6OOCCBlal~loCCOO(CH~)6•OOCCH=OHCO--],, (2). Comparative studies of the thermal stability of unsaturated polyestercarborane-styrene and -acryloni~rile copolymers indicated that the former has a higher stability than the latter (the temperatures for a 5 ~ weight loss in air are 300400 ° and 250-280 ° respectively) hence the former copolymer was studied in more detail. It was shown that changes of boron content in the range 3-16~o had no appreciable effect on thermal stability, which in most cases exceeded t h a t of the polyestercarborane starting materials [1]. According to published data [8-10], the thermal degradation of polyestermaleate-s~rene copolymers begins at lower temperatures than that of the polyestermaleates, which the authors of the above articles explain in the first place by rupturing of the C--C bonds between the main polyester chain and the crosstinking agent. The higher thermal stability of the solidified unsaturated polyester carboranes in comparison with the unsolidified ones may apparently be explained by the ability of the carborane groupings to stabilize homolytic cleavage of the polymers [11]. A study of the chemical stability of the styrene copolymers of unsaturated polyestercarboranes, estimated from the weight loss of the samples after keeping them in 3 0 ~ sulphuric and nitric acids for 3 days, showed that they are degraded under these conditions (0.2-8.0~/o weight loss). Unsaturated polyestercarboranes, solidified by irradiation, have the best chemical stability.
nomer
1:1.5
1:1 1:2 1:1.5
Styrene Styrene Styrene
8
9
10
Polymer of structure I I
Styrene
Acrylonitrile 4 - 0 : 1 1:1.5 Styrene
1:1.6 Styrene Acrylonitrile 4 - 5 : 1
Polymer of structure I 1 : 1.33 Styrene
Monomer
1:1
{[--O(CHs) a 0 0 C C H = C H C 0 ] ~ " - - 0 (CHI).OOCCBIoHIoCCO}.
[--OCHIC -- CCHIOOCCBIoH10CCO---],
[--0CH2CH=CHCH~00CCBIoHI.CC0--].
Formula of polyester unit
Weight ratio polyester : m o -
Styrene
No.
peri. ment
][~x-
Benzoyl peroxide Tert -butyl peroxide (1) Tert-butyl peroxide (1) No initiator
Benzoyl peroxide (1.0) No initiator Tert -butyl peroxide (0.5) No initiator Benzoyl peroxide Dicyelohexylperoxycarbohate
Initiator, wt. %
160 80-100 52.0 0 24"45
80 120 120 160
75.0 90.0 85.0 76-0
14.56 9.19 16.40 9-96
50
120 160 48"5 35.0 8.22 27.33
80
Solidification temperature, °C
54.0
Gel fraction yield, %
12.28
%
content in eopolyreeF,
Boron
STYRENE AND ACRYLONXTRILE UNDER 1 0 0 0 M P a oN THE GEL FRACTION YIELD
TABLE 2. EFFECT OF PROCESS CONDITIONS IN TJ:l.lg OOPOLY3fERIZA.TION OF UI~SATU~gATED m-CARBORANE-CONTAINING POLYESTERS WITH
g
0o
Methods of crosslinking unsaturated carborane-containing polymers
1149
Thermal stability, resilience, i m p a c t strength and density were evaluated for the styrene-polyester-m-carboranes of structure I I I . I t was found t h a t as t h e boron content increased, the i m p a c t strength was decreased, resilience increased a n d density a n d t h e r m a l stability were practically u n c h a n g e d (see Table 3). .An evaluation of the quantitative effect of boron content in the copolymers on their adhesion properties was carried out on polyester-m- a n d polyester-ncarboranes of structure I I I b y means of comparative tests on the shear of a l u m i n i u m plates, glued with styrene solutions of the u n s a t u r a t e d polyester carboranes a n d of the analogous polyestermaleates containing no carborane groupings. TABLE 3.
~PHYsICOI~ECHANICA_L
CHARA.CTERISTICS
TURATED
POLYESTER
OF
THE
STYRENE
COPOLY~ERS
OF
UNSA-
-m -CARB ORANE
( -- [O (CH,) ,OOCCH----CHCOJkO (CH~)~OOCCB~0H~0CCO}~ Content of polyester in copoly~ner,
%
Thermal stability, °C
Resilience, kg/cm2
Hardness (Brinel), MPa
Density at 20°, g/cm a
Elastic modulus E × 10-a, MPa
1.7 1.3
1.3 1.7
1.18 1.I3
1.57 1.00
i
28 13
140 I40
t 1
The results are presented in Table 4. As Table 4 shows, the shear resistance of a glued joint, in t h e case of m-carborane-containing copolymers, exceeds b y 50°/o a n d more the same characteristic of the analogous polyestermaieate (earborane group absent). A change of boron content in the original polyether has practically no effect on t h e joint durability. During the tests on samples glued b y styrene solutions of n-carboranecontaining u n s a t u r a t e d polyesters (Table 4, polyesters 3 and 9), it was found t h a t modified m-carborane dicarboxylic acid only improved the adhesion properties of the u n s a t u r a t e d polyethers slightly.
Startiny ma~,rial~. Unsaturated m- and n-carborane-containing polyesters were synthesized by the method of reference [1]. Chromatographically pure carborane dicarboxylic dichloranhydrides were used in the latter. Table 5 gives some of the properties of the polyestercarboranes prepared. 1,1,2-Trichlorobutadiene-l,3 was synthesized and purified by the method in reference [12], stored in sealed ampoules at dry ice or liquid nitrogen temperature. It was distilled under nitrogen, in vacuum (b.p.~32°/665 Pa, n~=1.5345, d-~ 1.37 g/cma; the literature [12] gives b.p.----32°/665 Pa, n~----1.5350) before use. Styrene was purified by a known method [13]. After twice distilling over a molecular sieve, in a current of argon, it had a b.p. of 145.2°, n ~ = 1.5468, d--~0.906 g/cma. Aerylonitrile was also purified as in reference [13] and distilled under argon (b.p.--~77.3°, n~=1.3910, d~0-8060; according to reference [13], b.p.----77.3°, n ~ 1.3911, d=0-8060 g/cma). Copolymerization of un~2turated polyesteroarboranes. A batch of polyestercarborane and styrene was stirred for 5-10 rain at 50-60 °. The styrene solution obtained was poured into
0
8
5 6 7
4
3
I~To.
ITler,
Poly-
{[_O(C~I,O),--OCCH=CHC0]~--O(CaH,O),--OCCB,~I{,oCCO--}s
I
{[--OCCH-~CHCOO(CH,)60]r--O(CH2)eOOCCBloHIoCCO--)* {[--OCCH ~--CHCOO(CH,) 60--],O (CH,) 6OOCCB loH~oCG0--}{[--0CCH~CHCOO(CH,)60]r-O(CH,) ,OOCCB,oHxoCC0--}* [--O(CsH,O)I--0CCH=CHCO--], {[--O(C~I,O) m---OCOH= CHC0]r--O(C,H40),--0CCB,oH,0CC0--),
I
[--OCCH=CHCO--O(GHI) e--]{[--OCCH~-CHCOO(CH,),O]r-O(CH,),OOCCB,oH,oCOO--}.
Polyester starting material
12"03
4600 4000
0"sllec,r
6.0 7-9 9"2 4.0 6.5 6.8 4*9
4"4 1 "24 7-32 3700
4.5 8"8
at 25 °, MPa
6030 3800 8000 4000 2470 6000
11-67 8"9 3"6
Boron con(%) in original polyesters tent
Molecular weight from terminal groups
TABLE 4. ST~NOTH OF ADHESIONOF ALUMINIU~IPLATES (Polyester : styrene weight ratio---- 1.0 : 1-0, glass transition temperature 80 °, holding time 6 hr)
Methods of erosslinking unsaturated earborane-containing polymers
1151
test tubes, 2% of benzoyl peroxide (on weight of original mixture) added and heated in an inert gas atmosphere at 80-100 a for 8-10 hr the copolymerization conditions are given in Table 1. The copolymerization of the unsaturated polyester carboranes with styrene and acrylonitrile under pressure was carried in Teflon ampoules at 80, 120 and 160° at 1000 MPa. The conditions are shown in Table 2. The irradiation of unsaturated polyestercarboranes was carried out in glass ampoulcs in equipment for radiation studies, with Co6°, with doses ferrosulphatc dosimeter. JMethod of s~udying the polyestercarborane~. The mean MWs were determined from she acid and hydroxyl numbers by the method of reference [14]. TABLE 5. POLYESTERCARBORANE STARTING MATERIALS
Polymer structure
Boron content,
I II III
35.19-37.90 18.41-29.00 1.12-11-57
%
Molecular weighs (from end groups)
Temperature for 5~o weight loss in air, °C
Ratio of unsaturated and carborane units
2600-4088 1770-3620 2400-9900
150-275 250-275 180-380
1:1 1:1 36:1
A 1-2 g batch of pulverized copolymer was placed in a tube with 30~o nitric or sulphurie acid, brought to boiling and then kept at 20-22 ° for 3 days. Then the oopolymer was filtered off, washed with water and extracted in a Soxlet for 18 hr to free it from low molecular weight products, after which it was dried in vacuum and weighed. Thermogravimetric studies of the polyestercarboranes and their copolymers were carried out at the polymers laboratory of the INEOS of the U.S.S.R. Academy of Sciences, on a derivatograph (rate of temperature rise, 4.5°/rain). The physicomechanical parameters of the test samples of solidified polyestercarboranes were determined as follows: thermal stability on a "Plastometer" apparatus at a load~lg of 10 MPa and increasing temperature: resilience on the "Dinostat"; Brincl hardness on a TP-1 apparatus, at 2.5 MPa loading; copolymer densities were determined in isopropanol; the limit of glued joint strength under shear by GOST 9147-65.
The a u t h o r s express their t h a n k s tx) V. M. Zhalin a n d A. A. sion a n d help in c a r r y i n g o u t e x p e r i m e n t s u n d e r pressure a n d for discussions a n d assistance in c a r r y i n g o u t e x p e r i m e n t s using m e t h o d of solidification. Tran~/ated
Z h a r o v for discusalso B. L. T s e t h n the radiochemical by C. W. C ~ e
REFERENCES 1. A. I. 80LOMATINA, N. I. BEKASOVA, V. V. KOR8HAK, Zh. P. VAGINA and A. V. D'YACHI~_NK0, Plast. massy, 9, 13, 1976 2. 8. L 01WEL'CHENXO, Slozhnye oligoefiry i polirnery na ikh osnove (Oligoesters and Polymers Based on Them). l~aukova duml~, Kiev, 1976 3. V. V. KORSHAK, A. M. POLYAKOVA and M.D. SUCHK0VA, Izv. Akad. Nauk SSSI~, Otd. Khim. n., 1111, 1959
1152
V. S. KImOAlCSKII et a/.
4. M. G. GONI~RERG, Khimicheskoye ravnovesiyo i skorost' reaktsii pri vysokikh davl e n i y a k h (Chemical Equilibrium a n d Reaction R a t e a t High Pressures). K h i m i y a , 1959 5. Y. V. SMITS a n d E. I. LOMTON, Science 113: 2947, 1951 6. Kh. S. BAGDASAR'YAN, Teoriya radikalnoi polhnerizatsii (The Theory of Radical Polymerization). Nauka, 1966 7. N. G. VlDENINA, Dis. na soiskaniye uch. st. kand. Khim. n a u k (Disc. on Thesis, Candit a r e in Chemical Science). I.Kh.V.S. Akad. N a u k IYkrSSR, Kiev, 1969 8. O. I. SAVlCHEVA, Dis. na so iskaniye uch. st. kand. khim. n a u k (Disc. on Thesis, Cand i t a t o in Chemical Science). 2qlIPM, 1972 9. E. G. ZIL'BERMAN, Dis. na soiskaniye uch. st. kand. khim. n a u k (Disc. on Thesis, Canditate in Chemical Science). I~IIPM, 1972 10. B. M. KOVARSKAYA, A. S. STRIZHENOVA, N. I. CHIBISOVA, Ye. G. GINTSBERG, E. V. MIKHAILOVA a n d Ye. L. KAGANOVA, Plast. massy, 5, 5, 1965 11. Yu. L. AVETISYAN, P. I. GRIBKOVA, S. A. PAVLOVA, I. A. GRIBOVA a n d V. V. KORSHAK, Vysokomol. soyed. A21: 502, 1979 (Translated in P o l y m e r Sci. U.S.S.R. 21: 3, 550, 1979) 12. T. MATSUDA and T. JUMOTO, Bull. Chem. Soc. J a p a n 40: 8, 1991, 1967 13. Kh. SERENSON and G. KEMPBEL, Preparativniye m e t o d y khimii polimerov (Preparative Methods of Polymer Chemistry). Mir, 1965 14. V. V. KORSHAK and S. V. VINOGRADOVA, Geterotsepnye poliefiry (Heterochain Polymers). lXlauka, 1968
Polymer Science U.S.S.:R.Vol. 25, 1~'o.5, pp. 1152-1161. 1983 Printed in Poland
THE
0032-3950/83 $10.00+.00 © 1984 Pergamon :Press :Ltd.
SYNTHESIS OF HE~TEROFUNCTIONAL POLYMERS PEROXIDE AND ANHYDRIDE GROUPS*
WITH
V. S. KURGANSKII,V. _A_.PucmN, S. A. VOROl~OVand V. S. TOKAREV Lvov Polyteclmical I n s t i t u t e
(Received 1 Dseember 1981) New heterofunctional polymers were prepared b y copolymerization of 5-tertbutylperoxy-5-methyl-l-hexene-3-yne with maleie anhydride a n d from a mixture of these two with styrene and the features of the process were studied. The synthesis of these polymers was found to obey the rules of inhibited polynlerization as a result of active participation of peroxidic monomer in the chain transfer and termination. For the first time an equation was derived for the rate of terpolymerization in the presence of peroxide monomer which satisfactorily describes the process, over a wide concentration range. F r o m this equation, the integral and differential compositions o f b i n a r y a n d t e r t i a r y anhydride-containing polyperoxides were calculated. * Vysokomol. soyed. A25: No. 5, 997-1004, 1983.