6SAYYAH, SABBAH and SAID: Characterization and radiometric studies on poly(methy1 methacrylate) chain a n d t h e adjacent molecules of either solvent or polymer (in a melt). In such a case, t h e above formulation would apply with t h e variation of pressure replacing ST in eqs. (13) a n d (14) a n d t h e variation of volume replacing SU. T h e complex bulk modulus of t h e same form as in eq. (15) will result, but in this case it will have a n isothermal contribution, possibly exceeding t h e thermal one. T h e latter can be verified experimentally, since it is t h e isothermal longitudinal modulus that governs t h e fluctuations observed b y correlation spectroscopy methods in t h e light scattering experiments. Furthermore n o correlation with C&, values is t o be expected for t h e structural mechanism, if t h e volume changes are more important than those of t h e enthalpy. This picture which involves structural rearrangements does n o t conform t o t h e model of a chain interacting with its surroundings as a macroscopic object does with a viscous medium. It is quite possible t h a t t h e latter model, in spite of its great success in explaining t h e general features of viscoelastic behaviour, will have t o be exchanged for t h e more detailed molecular picture when more subtle properties are considered. T h e above considerations seem t o show t h a t this can b e done without losing t h e benefits of t h e continuous-medium approach, while at t h e same time leaving room for t h e concepts underlying t h e theories of transition t o t h e glass-like behaviour. The desirability of such incorporation has already been mentioned [I, 11, 161.Some p-phenylene diamine condensation products with different organic acids were synthesized. The effect of y-irradiation on PMMA films doped with three samples of these amines was investigated by ultraviolet spectroscopy. A change in the intensity of absorption bands with increasing irradiation dose was recorded. The use of PMMA films doped with this type of amines as dosimeter is suggested. Charakterisierung und radiometrische Untersuchung von mit Aminderivaten dotiertem PoZy(methyZmethacry2at)Einige Kondensationsprodukte von p-Phenylendiaminen mit verschiedenen organischen Sauren wurden synthetisiert. Der EinfluB von y-Bestrahlung auf PMMA-Filme, die mit drei Proben dieser Amine dotiert wurden, wird mittels UV-Spektroskopie untersucht. Es wurde eine Zunahme der Intensitat der Absorptionsbanden mit steigender Bestrahlungsdosis registriert. Die Verwendung der dotierten PMMA-Filme in der Dosimetrie wird vorgeschlagen. Xapakmepucmuxa u paauoMempuueckue uccfieaosanus noJcumemuJcmemaxpuJcama, ~omuposannozo npouesoanbwu m u n aCHHTeTH3E1pOBaHbI HeKOTOpbIe IIpORYKTbI KOHJ(eHCa~HE1 n-@?HHJIeH~E1aM%iHOB C pa3JIHqHbIMM OpraHHYeCKUMM KMCJIO-TPMII. c I I O M O 4 b H ) Y@-CneKTpOCKOIIHE1 IlCCJIeROBaJIOCb BJIHFIHIle y-JIyqe8 H a IIJIeHKIl E 1 3 nMMA, ROTHPOBaHHbIe TPeMFI Ha aTMX aMIlHOU. HaBn~o~anocb YUeJIllqeHHe IlHTeHCHBHOCTIl a6cop6qm C POCTOM R03bI 06JIyYeHHX. ripen-JIaraeTCx ...
New semiconducting copolymers were prepared by bulk copolymerization of methyl methacrylate with chromium acrylate. The pattern of the chemical reactions is discussed. The density and hardness of the samples decrease with increase of the chromium content. I n the infrared spectrum broadening of the carbonyl band a t 1710 cm-l is observed, which indicates the possibility of coordination of the C=O group with the chromium ion. The electrical conductivity of the samples increases with increase of chromium acrylate content. The effect of y-irradiation on the electrical conductivity of the copolymers was studied. Physikalische und spektroskopische Untersuchungen an Methylmethacrylat-Chromacrylat-CopolymerenDurch Substanzcopolymerisation von Methylmethacrylat und Chromacrylat wurden neue halbleitende Copolymere erhalten. Das chemische Reaktionsschema wird diskutiert. Dichte und Harte der Proben nehmen mit steigendem Chromgehalt ab. Im Infrarotspektrum wurde eine Verbreiterung der Carbonylbande bei 1 710 cm-l beobachtet, was auf eine mogliche Koordination der C=O-Gruppe mit Chromionen hinweist. Die elektrische Leitfahigkeit der Proben nimmt mit steigendem Chromacrylatgehalt zu. Der EinfluB einer y-Bestrahlung auf die elektrische Leitfahigkeit der Copolymere wurde untersucht. Duauuecxue u cne?cmpocxonuuecxue uccJceaoeanu.m cononwepoe aemwuwmaxpmamau axpunama xpo.wa B~O Y H O~ c o n o n n~e p~3 a q~e 8 MeTHnMeTaKpHnaTa II aKpmnaTa xpoMa nonygeHbI Home nonynpoBoEsqHe COIIOJIM-MepH. 0 6 c y x~a e~c s CXeMa XHMHYeCKHX peaKqHt. nJIOTHOCTb H TBepAOCTb o 6 p a a q o~ YMeHbIUaIOTCR C POCTOM coxep-HCaHHR XpOMa. B HH CIIeKTpe ~a6n10~(anocb paCIIlHpeHHe Kap60HHnbHOft IIOnOCbI npH 1710 CM-l, 9 T O yKa3bXBaeT H a BOBMOH(HYI0 KOOp$(HHaqHIO c=o rpJTIII C HOHaMH XpOMa. aJIeKTpH9eCKaR npOBOEHMOCTb 06pa3qOB yBeJIH914-BaeTcR c POCTOM coxepmanm xpoMa. Hccnenosanocb B n m m e y-nanysemis H a aneKTpHsecKym npoeojpiMocTb CononHMepoB.
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