. l D ~ O K P T I O S O F C O R R O b I O S I S H I B I T O R < O S I R O S . I S D \TEEL
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IYTRODI~('T10S
Diiring the course of ;in inr-c>tigntion of cwrroxion inhilJition hy polar org:inir substances, it \vas tlecaitled that :i study oi the nictal ai11,f;iccv erpos;cd to these materials might be iiindc profita1)lj- 1)y t~lcctrontlift1,act ion nict liocls, since the initial ,step in the niec~1i;unianiis almost csertainly o~i(:of at1,wq)tion of tlie inhihitor molecules on the metal ,,~ii,face ((;). This concluxiun c.ori,ol)or:ited cind extended 21 siniilai, vie\\point h ~ l t I)y l ;i ni1nil)cr of otlici, \\-oi,l;ers in the field ($1). The striicture of several such >uhstcinw> pl:rc*ctl on n i c t d siu,i':i stiidietl extensir-elj- hy Gc1,mei. ant1 Storks ( 3 ) i1~onieic>ctron (!ift'r:iction patterns. -1report on the fornxition of olcopho1)ic films on met:il q i r f : i c c ~( 2 ) ant1 :in investigation of the stnictiirc of these films (1)Lippeared r v l i i k tlicl prcscnt \\xi,li,ctl conr-incing p i ~ o fthat ntlsoiption of po1:rr organic moleciilri o n nictal ;r11f:icrs clw~t d i e place and that the striictiirc of tlic aclsorl~etlfilm i,5 t l i i t l Iiii~gclj~ t o tlw 11~-(!1~0curlion end of the molecule. In the 1voik iqiorted hloiv sonic 1-nriution in $1 rrictiire \ \ x s fount1 Tvit li (Iiffcrent materials, tlic clift'eiwice ljcing tliic piniarilj- to tlic niinil)cr of atisorhod layers or to the orientation of the molecule to tlie metal ~i,f:ice. I n addition, evidence for variation in tlie strength of aclsurption l)ontl,i \\.a> obtained. Finally; it \vas foiiiid that in jeverai cascs :I finitc. rate of orientation of t'he adsorbed film )vas observed and that it \vas pos,sil)l(>in a fc\\. i m t m c w to clctermine this rate 11y direct metisui~enient, The application of the information ohtained in this study t o thc inhibition of corrosion will appear in a separate publication. ExI'EIII~II:sT.\L r 7
1lie instrmicnt used in this it-ork uxs a n RC-1 tj-pc 11111--1 elcvtloii microscope. This instrument has n port into n-hich an electron clift'raction attachment is fitted. To obtain transniission pattern> the sample is placed on :I fine rire mesh, ii-liich in turn is placed into a holder arid fnstenecl to the tlift'riiction ~ttarlimenthy means of a mol-nljle pin. I n order to ohtnin reflection patterns I'reeeiitetl liefore t h e Diyiiion of Colloid C'hemistr>-:it t h e 113th S:itioii:Ll meeting of -lie A h i r r i c : i i i Clicniic:il docict>-, Chicago: . i p r i l , 1948. 13:isetI i n y i r t 011 :i thesis su1,initted t o t h e Gr:rtlu:ite Scliool of thr Pnivrr,sity trf' Texis II p:irti:il fulfilliiiriit of t h e requirements for t h e P h . 11.degree. lI:iy, 194s. ~'I'eiellt ntltirrss : The Ger1er:il p:lcctric ConiIxiny, ~ ~ i c h l a i i t\-:i,shitigtofi, d,
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