Ida Mitsuo

井田 光雄

Kanazawa University Repository for Academic Resources

--23ーThe Science Reports of the Kanaza，wa University Vol. H. No. 2 pp.23--30. March 1954 On tJ，e Dielectrics treated by an Electric Field 1. Mitsuo IDA (Re白 ived21. Dec. 1:153) I ntroduction Withrespect to the properties of the dielectrics solidified under an electric field， くl)several researches have been made in connection with the electrets. For some years the author has been studying the properties of the dielectrics gener-_ ally treated by an electric field， and a report of his experiments together with the discussion of the dielectrical properties concerning cetyl alcohol， lauryl alcohol and amilan (polymer) which have hydrogen bonds are given below. Experimental procedure The arrangement of the experin;ental apparatus is ilILstrated schematically in Fig. 1. a。型空f竺Js ιよ」Fig 1. Arrangement of the experimental apparatus The sample was placed in the plate condenser C， whose electrodes Cdiameter : 7.4 crn) 物 wereinsulated by three glass spacers (thickness : 1.4 mm). The surfaces of the electrodes were nickel plated. The capacity of lhe condenser was approximately 34/111 F. The condenser was put into an air thermostat A. The temperature of the sample was recorded by a copper constantan thermo・junctionT. Sin白 thecondition oE the solidification of the meIted sample affected the experimentaI results， the following procedure was taken except in special cases. After removing the cover G the current of the heater H was. opened， and the samplewas cooled spontaneously. When the ccoling was made under an e1E:ctric field， switchs S and Sl> or S and S2 'Were closed， and opened after one hour. All measurenments were mad one day after the solidification. In order to measure the dielectric constant and electric conductivity at the same temperature， switch S was - 24- MIDA connected with S8， S4， S5 by tumes. First， S was connected with S8' and the dielectric constant was measured by a low frequency bridge under the‘frequency 2 K C. per seeond. The balancing of the bridge was detecled by ihe method as shown in Fig. 2" which can read the maximum current bya microammeter. Fig. 2. NuIl detector . Nextly， S was connected with S4 and位lemeasurement of high frequency 3 M. C. W<lS made by a heterodyne beat method (Fig. 3). 6SA7 6V6 包CFig. 3. Beat frequency cscilIator Finally S was connected with 85 and the electric conductivity was measured by aバgalvanometer. The time rate of the teinperature rise was so small that the tIme nec四saryfor the sample to rise from the room temperature to the meHing point was about four hours. Therefore the eHect of the current， which was resulted when the sample solidified under an electric field was warmed again， perhaps could be neglected.ω. (3).(4) Experimentαl Resultsαnd Discussions Cetyl alcohol Crude cetyl alcohol was once fractionated at a reduced pressure using a fractionating tube of 1 m in length. The mJting point was 48.5旦-490The fact that the dielectric constant oI the sample solidified under a D. C. electric -25一field will decrease from the normal v<llue (say Do C. eUect) has alrεarly むeenrq~ortεd. 全長 The author care[ully confirmed this. And the fact that the diekctric constant of the s3mple solidifiecl under an A C. (fiOcycle) eledric field wil1 inrcease aむovethe normal value (say Ao C. eftεct) W2S newly founcl. Both eHects are shown as in Fig. 4. Curve (1) is for a sample solidified without electric field， curve (2) and (B) C01"1"eιponc1s respcctively to the case where 1he sample WelS solidified l!Ilder the elεctric field 01' D. C. 1 I<V or A. C.l KV. Fig. 4 is for the measurements by the frequency:2 K.C. 1n 1he C2~~εof the frequency B M. C. per ~:econd ， bott! D. C. and A C. effects could not be found. For electric C'onductivity similar effects were found as shown in Fig. fi and Fig. G. Curve (2) in Fig. [) 1S for D. C effeft， and curve (2) In Fig. fi corresponds to A.C.εffer:t. the also 。nthe DicleclTics t?'caicd by臼11 Elcctric F'i仙一lト???? ?i(τ(ドグ ilLf:L Fig.4. D. C唱 effect3nd A. C cOl1stant (2， K. C.) {.Oυ やfJi :¥(10 200 ???????? ?J I¥ 1 SDη う"。20( h仰Fig. 6. AC. effect for the electric conducti vity D.C， e紅白ctfor the electric conductivlty Fig.5. K. Asai・Lecture :lt the Phys， 80c. Me巴tingat ()sal:3.， Ni)VeniberJ 1臼日O.‘' ←-2s - M. IDA /~一一一一一一一~一/ 1n order to find out the causes of ihe D. C， or A. C， efiect， ihe following prcc合dureswere attempted. ( 1) The electric current with the sample under an el巴ctric field was measured. The result is shown in Fig. 7 The curves Ol D. C. and A. C. are quite diHerent， in spile of the same /八一」一一 voltage 900 V， Fig守 7， Variation of the electric current with time (、2) W11en the sample w11ich had shown D C. effect was melted and solidified again， D. C. effεct a1most remained unchanged. ( 3) When the D. C. electric field was applied to tbe sample in liquid and removed as 800n as the solidification began. D. C. effect was not seen， ( Ll) In case the D. C. electric field was applied in the 801id slate (270C or 400C)， D. C. eHεct was seen. ( 5) A sample which had shown D. C. effi:ct was melted and solidified under an A. C. electric field. A C. ef[ect was seen. Ca向dt:1 ( 6) ，九Then th台 sample which had shown A C。，4dt "例"岬印。初 50ιFi宮， 8. Variation of A C effect with voltage く2K.C.)εffect was mel1ed and 宮olidifiedagain， A. C. effect remained aJmost unchanged. ( 7) When the A. C. electric field was applied in liquid and removアεdas scon as the solidificaLion began to take place， A.C. eHect was seen， though slightly. (8) When the A. C。εkctricfield was applied in solid， A. C. ef{ect was not conspicious. The eHect seems 10 be most remarkable if the A.C. electric field was applied continuously frorn the liquid 10 the solid. ( 9) The higher the A. C. voltage， the larger was the A. C. e{fect as shown in Fig¥8幽(10) When a sample which had s110wn A. C. effect was rnelted and wlidifJed under an D.C. eleclric ueld， some D.C. eHect tcok place. (11) The samples used in the experiment were not εxtra pure， but it 8eεmed that the less pure， the smalJer was the efたctof the electric field。From the preceding experimental results the author came to a conclusion as follows. ( 1) D.C. effect is due 10 ihe decrease of hydrogen 011 the Diclecir官、8t?・eaiedbyαη Elecfric .F?'rld 1. - '27 -bonds r田 ultedfromthe pl吠 onconduction in solid. ( '2) A. C. eHect is due to the increase of hydrogen bonds resultεd (r011 the aclion like a stirring by A. C. current when the liquid solidiues. ( n) Moreover， for the 'explanation o{ the experimental results， it is necessaτy to assnme that the structure of alcohol is not εreat1y clifferent whether it is liquicl or solid. (5) But for the verification of theE:e日uppositionthe author thinks it necessary to stuc1y some other properties. LU'lIryl !tTl・oholBernal くの has reported from his X ray sjudy the r01ational 1ransition of lauryl alcohol， but Otto (7) has 1:0t founc1 any anomalies. By thermal analysis Phillips and Mumforc1 ∞found the transition in the cooling curve. but not in lhe heating. FrOEch'.9) fOllnd the dielectric anomaly， which could not be detected by HoHman and Smyth.C1()ヲHoUman and Smyth purified 1he sample carefully， (ils m. p. was 2).50) and fOllnd the ~urve 部 shownin Fig. 9. 定6 /.併、h旬、町-s 」チ3 --司-<.-咽ゆ褐醐-.20 2'5 'ι 。 .2() ~O 。ιFig. ~). Dwlectric constant for pure sarnple (Hoffrnan and Srnyth) Fig. 10. Dielectric ('onstant for 'mpure sarnp!e (Hoffnnn 日ndSmyth) The curves at 0;5 K. C. and 5 K. C. coincide in cases 0干bothheaung and cooling. This shows there is nO anomaly. Furthermore they have shown the result as Fig. 10 in case of impure sample， and explained the maximum of the curve as the r倒 1tof the action of some impurities sllch as hyc1rate， and not as the result of transition of lauryl alcohol. And they supposed that Frosch was mistaken in conceiving the maximum due to hydrate as the transition phenomena.楽Hereupon 1he author measured the dielectric constant and clectric conductlVity in warming and cooling before he sludied the eflect o{ the electric field. 手i:. The author has had no oppot日nityof H~eing Frosch's original paper. The sample was fractionated as cetyl alcohol. Its m.p. was 22.5~230. 書長In order to compare the impurity with thaf of prior investigators， the electric conductivities in ljquid 〆areshown as follows. Hoffman and Smyth Frosch 17 X 1.0-10 42x 10-10 M. [DA ??? ????????、???????????? ? ?????，?????of The author results shown as in The 13 Cαpadt)f ，.、ι.、司，、800トイ ν、乎4 、12KC 、ー帯、、ヘ令%、"、叶、J 弘+¥ t 、(3 )浜‘、1 〆.ω‘， p、J寺、 i¥ (2) / . ， 、 ，??- 28ー'100 2KC 600 500 400 300 3MC Fig. 1. D.C. and A.C. e妊ectfor the dielectric constant. ??????'C 30 20 10 CatαCLttf ClLrrent 4000 /500 V 1200 0) 3000 2000 /000 2κc f)00 goo 600 ℃ 30 20 /0 ，20 30 'c Fig'. 12. Temperature dependence of the die. I白ctricconstant in the cooling process. Fig. 13. D.C. effed fot the eledric conductivity. It was kindly 0仔eredby Prof. J. Noguchi 母号。nthe Dulectrie.3 treaied by 白川 Eleo[J'μ Field L 2H --The transition phenOmeuel can thus be clearly seen both in Wal‘ming and but esp巴ciouslymore 80 in cooJing. ιυo1ing， 1n Fig. n and Fig. 12 the curv出 by2 K. C. anc1 g 1叫.C do not coincide， alld this fact shows that the sample (}f the author had theνurity Iower than of Hoffrnall and Smyth. Whel1 the sample w礼"solidiued under a D.C. electric fic!d， the results shown in the curve (2) il1 Fig. n and Fig. 13were obtained. Fig. 11 shows the maximum of the right side disappeared by the D. C. electric fic1d. By ιomparing with the case of cetyl a1cohol， itcall by assumed， therefore， that the maximum was due to the transition. From Fig. ls the same thing can be assumed. Conversely the maximum of the left side in Fig. 11 did not disappeared， but was somewhat elevated by the D. C. electic field. So it is supposed that the maximum wilI correspond to that oE irnpm・esample of Hof{man and Smyth. Therefore the transition seemed occur when the purity of the somple was between the purity and impurity of Hoffnle'ln and Smyth. It can be supposed that the transit.ion point was lowered by a minute impurity and appearecl before the melting. Such a faιt had oJready been measurement of specific. heat.く11)found by Kakiuchi， Sakurai and Suzuki in the When the sample was solidiJied under an A. C. electric field， the result was the curve (3) shown in Fig. Jl， but the explanation for this cannot be given satisEactorily. 11 the case of 3 M. C. measurements， nO electric field eEfect in both D. C. and A. C. was found as in the case of cetyl alcohol. Amilαn Amilan is a polymer as a Nylon which has hydrogen bonds. The sample was kindly offered by Toyo Rayon Co. 1ts m.p. was about 2100 • It was titted between the electrodes of the condenseτhy me1ting it in vacuum tG prevじntoxdization. The dielectric constant curve was as (1) in Fig 14 or Fig. 1o_ When the sample was treated by D. C. electric field in the solid state (] 400)， its current RIJO 600 400 2()O (apQcil"，!f /" /'"， ←一一一/三<~/ ， / / / 一一一一一一一-30 -5'0 'l(! 卯 110 130 ・cFig. 14. D. C. effect-for the dielectric constantく2K固 C.)Capadty ( 4) ヲ500 一一一一一→一円 一-~一一一一一一ゐ一一------'一一一一一一←一 .-'rO ，0 80 !QiJ ι Fig. 16. A. C. effect for the dielectric constantく2K.C.) 一-30 一 M IAD was about 200，I1A， for 14 hours， and the result was as in Fig. 14 showing a decrease of dielectric constant. When the sample was tr朗 tedby A. C electric field in the solid state (1400)， its current was about 0.7 mA， fo1' 5 homs， and the result was as (2) in Flg. 15 showing a1so a decr田町 ofdielectric constant. Although these treatments were made in vacuum some exdization and thermal decomposition might have taken place血 Butthe cause Ot the electric e{fect sεemed chiefly due to the decrease of hydrogen bonds. In conclusion the author wishes to express his Sl11cere thanks to Dr. Y. Kakiuchi and Professor H. Shyoji for their kind gU1dance. He a180 expresses his gratitude 10 Toyo Rayon Co. for the gifts o( amilan， and to Mr. A. Tanal王aand T. Koikeda for theu・cooperation.Reference昌( 1) Gutmann: Rev. Mod. Phys. 20 (1948)， 475. ( 2 ) G.Groetyinger and H. KretEch: Z.f Phys. 103 (1933)， 337. (3) H. Frei and G. Groetyinger: Phys. Z. 37 ， 720. ('1) Y. Kakiuchi: Sci. L P. C. R. 40 (1943)， 18H. ( [) Pauling: The Naiure o[ the chemic司1bond (19主8入308⑨( ()) Bernal: Nature 123 (lD32)， 8'70. ( '7) Otto: Z. Physik. Chem. 193 218 ( 8) Phi1lip andはu.mford J. Chem. Soc. 663. ( 9) Frosch: Ann. Physik. '12(1942)，254. (10) 1. D園 Hoffman and C.P. Smyth: 1. Am. Chem Soc. 71 (1946) ，もヲ1.(11) Y. KakiuchL T. Saku1'ai and T. Suzuki: 1. Phys. Soc. Jap. 5 (1%0)， 369. 

On the Dielectrics treated by an Electric Field. I

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On the Dielectrics treated by an Electric Field. I

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