Khảo sát khả năng ức chế ăn mòn thép CT3 của một số hỗn hợp ức chế thân thiện với môi trường trong màng sơn hữu cơ

Tap chi Hoa hgc, T. 48 (4), Tr. 511 - 515, 2010<br /> <br /> <br /> KHAO SAT KHA NANG LTC CHE AN MON THEP CT3<br /> CUA MOT SO H 6 N H O P LTC CHE THAN THIEN V6l MOI TRl/ONG<br /> TRONG MANG SON HUrU CO<br /> De'nTda sogn 14-10-2008<br /> DAO QUANG LIEM, N G U Y S N V A N TAM, BUI QUANG TUAN<br /> ,, •; LAI THI HOAN, PHAM TIEN LAM,:®HUAT QUANG SON<br /> Bg mdn Hda - Trudng Dgi hgc Giao thdng Van tdi<br /> <br /> <br /> ABSTRACT<br /> Organic coatings can not completely separate metal substrates from aggressive medium, so<br /> the present of inhibitors in organic coatings plays an important role for inhibitive ability of these<br /> coatings. Some traditional inhibitors, such as ZnCr04, Pb02..., have been used for along time, but<br /> these inhibitors are toxic. Therefore, finding new environmental-friendly inhibitors has been<br /> attracted many researches. In this work, we would like to present some result about properties of<br /> calcium phosphate molypdate (CPM), mixture of zinc molypdate and calcium phosphate (ZMCP)<br /> in epoxy coating on CT3 steel. Inhibitive properties of these inhibitive systems are investigated by<br /> electrochemical methods: monitoring open circuit potential and electrochemical impedance<br /> spectroscopy, electrochemical polarization curves. Influence of these mixtures on mechanical<br /> properties of this coating system is also investigated. The results show that these inhibitive<br /> systems have good anticorrosive ability and they do not change the mechanic properties of epoxy<br /> and alkyd coatings.<br /> <br /> <br /> I - DAT VAN DE Trong bai nay chiing tdi trinh bay mdt so kit<br /> qua nghien ciiu kha nang tie c h i an mdn cita he<br /> Son phu la mdt phuang phap bao ve chdng calcium phosphate molybdate (CPM) va he zinc<br /> an mdn kim loai rat hieu qua, de nang cao kha molybdate va calcium phosphate (ZMCP) trong<br /> nang bao ve cita cle mang son su cd mat cita mIng epoxy. Kha nang nang cao do bin chdng<br /> cac lie chi rat quan trgng. Da tii Mu ngudi ta sit an mdn cita cac he itc c h i nly dugc khao sit<br /> dung cle hgp chl't crdmat lam chat lie c h i trong bang phuang phap tdng trd dien hda, dudng<br /> mIng son rit cd hieu qua. Song cac hgp chl't<br /> cong phan cue va theo ddi t h i mach hd theo thdi<br /> crdmat cd tfnh chit ddc hai Inh hudng din mdi<br /> gian. Cac phep thif tfnh chit co If cita cic he son<br /> trudng sdng, vi vay viec tim ra cle chit lic c h i<br /> khdng ddc hai d i thay t h i cho cac hap chit dgc tren.<br /> hai la mdt viec rl't cd y nghia vl dugc nhiiu nha<br /> khoa hgc quan tam. II - THUC NGHIEM<br /> Nhirng kit qua nghien ciiu gin day cho thiy Trong qui trinh thuc nghiem chiing tdi sif<br /> mdt sd hdn hgp mudi tren nin anion phosphate<br /> dung cac hoi chit tinh khiet: Zn3(P04)2,<br /> va molybdate cd kha nang tie ehi an mdn kim<br /> Ca3(P04)2, ZnMo04 va CaMo04. Cac dung dich<br /> loai cao va cd thi thay the cac chit lic chi<br /> truyin thdng ddc hai [1 - 4]. dugc pha chi bang nude clt.<br /> <br /> 511<br /> 1. Danh gia kha nang lic che ciia cac hdn hgp Cac miu son dugc phit tren nin thep CT3 vdi<br /> tren chiiu diy 90±3 pm. Miu son dugc gin dng<br /> Kha nang bao ve chdng an mdn thep CT3 PVC dudng kfnh 60 mm, chiia dung dich NaCI<br /> trong mdi trudng NaCI 0,5 M dugc dinh gia 0,5 M.<br /> bing phip do trong dung dich NaCI 0,5 M CIc phep do dien hda dugc thuc hien tai<br /> khdng cd mat va cd mat hdn hgp mudi bao hda Phdng thf nghiem Hda trudng Dai hgc Giao<br /> neu tren. Cac dung dich nude bao hda cac mudi thdng Van tai tren thiit bi do dien hoi da nang<br /> tren dugc dieu chi bing each: cho mdt lugng du PGS AUTOLAB 30 kit ndi mIy tfnh.<br /> cac mudi vao dung dich NaCI 0,5M khuiy trong 3. Danh gia tinh chat co if cua cac mang son<br /> 4h, Igc liy dung dich.<br /> Do bam dfnh, do bin udn, do ciing, do<br /> *) Binh do dien hda gdm 3 dien cue: bdng... dugc dinh gil theo cle TCVN tai Phdng<br /> - Dien cue lam viec (WE) - la thep CT3 cd thf nghiem Vat lieu, Vien Ki thuat Nhiet ddi,<br /> dien tich bi mat 0,79 cm^ xung quanh dugc bgc Trung tam Khoa hgc va Cdng nghe Viet Nam.<br /> epoxy, dugc mai bdng, kbit md va tay gi. Vat<br /> lieu lam dien cue thep CT3 cd thanh phin: Fe Ill - KET QUA VA THAO LUAN<br /> (99,406%),' C'(0,150%) S (0,037%), Mn<br /> (0,420%) va Si d dang vet. 1. Kha nang u'C che an mdn thep CT3 ciia<br /> - Dien cue ddi (CE) la ludi Pt. hdn hgp CPM va ZMCP trong mdi trudng<br /> - Dien cue so sinh (RE) la Ag/AgCl/KCl NaCI<br /> 3M. a) The mach hd cua dien cue thep CT3 trong<br /> 2. Danh gia tac dgng cua cac hdn hgp urc che cdc dung dich nghien cicu<br /> tren trong mang son epoxy Do phan cue t h i tinh (potentiostatic) cita<br /> CIc miu son epoxy cd mat vl khdng cd mat dien cue thep CT3 trong cle dung dich nghien<br /> cle hdn hgp lie chi tren dugc chi tao tai Phdng ciiu cho tha'y su biin ddi thi mach hd cita thep<br /> thf nghiem Vat lieu, Vien Ki thult Nhiet ddi, CT3 trong cle dung dich tren theo thdi gian,<br /> Trung tam Khoa hgc vl Cdng nghe Viet Nam. (hinh 1).<br /> <br /> -0.300T<br /> <br /> <br /> <br /> -0.400<br /> ><br /> (1)<br /> HI -0.500<br /> (1) dung dich bao hoa ZPCM<br /> (2) dung dich bao hoa CMP<br /> (2)<br /> (3) dung dich NaCI 0,5M<br /> -0.600<br /> (3)<br /> <br /> -0.700 0 1250 2500 3750 5000<br /> t/s<br /> Hinh 1: Su biin ddi t h i mach hd theo thdi gian cita dien cue thep CT3<br /> Kit qua hinh 1 cho thiy, hdn hgp itc che Do phan cifc tuyin tfnh dien cue thep CT3<br /> CMP va ZPCM lam tang thi mach hd cita thep trong dung dich NaCI 0,5 M cd mat va khdng cd<br /> CT3 - nghia II cd kha nang lam dich thi dien mat cle hdn hgp chit lie ehe tren cd the xac<br /> cue tii viing hoat ddng sang vilng thu ddng va lie dinh dugc mat dd ddng an mdn vl t h i an mdn,<br /> chi qua trinh an mdn thep CT3 trong mdi trudng tif dd danh gil dugc hieu qua bio ve cua cac hdn<br /> NaCI 0,5 M. hgp tren theo cdng thiic (1). CIc kit qua dugc<br /> b) Khd ndng ice che cua cdc hdn hgp CMP vd tdm tit trong bang 1.<br /> ZPCM<br /> 512<br />  c h i nay trong mang epoxy cQng dugc dinh gil<br /> Z = ^^^—^.100% (1) bing phuong phIp tdng trd dien hda. Cac hdn<br /> hgp lie chi nay dugc dua vIo mang epoxy dudi<br /> i II mat do ddng an mdn thep CT3 trong dung dang mdt chl't ddn. Sau khi dugc gia cdng tren<br /> dich NaCI cd mat cle mudi nghien ciiu. nin thep CT3 chiing tdi theo ddi the mach hd<br /> i„ la mit dd ddng an mdn thep CT3 trong dung cita cac miu son dugc ngam trong dung dich<br /> dich NaCI khdng cd mat cle mudi nghien ciiu. NaCI 0,5 M theo chu ki 7 ngly.<br /> Bang 1 va hinh 2 cho thiy khi cd mat cac<br /> hdn hgp lie chi, thi an mdn dich vi gia tri Bdng 1: Mat do ddng an mdn cita dien cue thep<br /> duong ban va mat dd ddng an mdn giam manh, CT3 trong cic dung dich lam viec<br /> chung td hieu qua bao dien cue thep CT3 trong Dung I.^,.lo-^ Z, %<br /> dung dich NaCI 0,5M. Hdn hgp ZPCM cd hieu dich Earn, m V<br /> A.cm ^<br /> qua bao ve cao hon hdn hgp CMP.<br /> NaCI 9,78 -620<br /> 2. Kha nang utc che cua hdn hgp CMP va 82,2<br /> ZPCM 1,74 -580<br /> ZPCM trong mang epoxy<br /> CMP 2,72 -590 72,2<br /> Kha nang tie c h i an mdn cua cac hdn hgp tic<br /> <br /> <br /> <br /> <br /> (1) dung dich bao hoa ZPCM<br /> (2) dung dich bao hoa CMP<br /> (3) dung dich NaCI 0,5 M<br /> <br /> <br /> <br /> <br /> 1x10<br /> -0.695 -0.645 -0.595 -0.545 -0.495 -0.445<br /> E/V<br /> Hinh 2: Dudng cong phan cue cita dien cue thip CT3<br /> <br /> Kit qua hinh 3 cho thI'y khi cd mat cac hdn giam nhanh theo thdi gian. Kit qua nly cho thiy<br /> hgp chl't lie che, the mach hd cua he thep CT3 hdn hgp CMP va ZMPC cd khi nang ning cao<br /> trong cac mang son tuang ddi duong ban khi kha nang chdng an mdn thep CT3 trong mdi<br /> khdng cd mat chit u:c chi. Han niia khi cd mat trudng NaCI kha tdt.<br /> cac hdn hgp lie chi nay thi thi mach hd llu bi<br /> sut giam ban khi khdng cd mat chit lie chi. Kit 3. Anh hudng cua hdn hgp u:c che den tinh<br /> qua cung cho thI'y cac hdn hgp lie chi tren cd chat CO li cua mang epoxy<br /> tac dung ning cao kha nang chdng an mdn thep Trong thuc t i sit dung, cac tfnh chat ca If<br /> CT3 cita mang epoxy. cita mang son ddng vai trd rit quan trgng. Vi<br /> Tuong tu, su biin ddi tdng trd tai 0,1 Hz cita vay viec dinh gil tie ddng cua cac hdn hgp lie<br /> cac he son dugc trinh bay d hinh 4 cho thay tdng chi nay ddi vdi tfnh chat co If cua mang son la<br /> trd cita mIng epoxy khi cd mat cichdn hgp tie rat quan trgng. Cac tfnh chit co If cita mang<br /> chi cao ban dang ke so vdi mIng khdng cd epoxy cd mat va khdng ed mat cac hdn hgp tic<br /> them hdn hgp lic chi. Hon niia khi khdng cd chi dugc trinh bay trong bang 2.<br /> mat cac hdn hgfp tie chi tdng trd cita mang son<br /> <br /> <br /> 513<br />  20 40 60 80<br /> Tho'i gian / Ngay<br /> <br /> <br /> Hinh 3: Su biin ddi thi mach hd theo thdi gian cua cac he son<br /> <br /> <br /> 10 -^oxy<br /> <br /> <br /> ^ M^^-^^^^^4=^|ziinr:4^ -CMP<br /> <br /> <br /> -ZIVICP<br /> <br /> <br /> <br /> <br /> 10 20 30 40 50 60 70 80<br /> Thai gian / Ngay<br /> Hinh 4: Su bien ddi tdng trd tai 0,1 Hz cua cac mang son<br /> <br /> Biizz^ 2: Tfnh chit co If cita mang epoxy cd mat va khdng cd mat hdn hgp lie che<br /> Chi tieu Epoxy CMP ZMCP Tieu chuan<br /> Dd bIm dfnh diem 1 diem 1 diim 1 TCVN 2097-1993<br /> Do bin udn 1 mm 1 mm 1 mm TCVN 2099-1993<br /> Do bin va dap 50kG.cm 50kG.cm 50kG.cm TCVN 2100-1993<br /> Dd Cling mIng son 0,27 0,24 0,22 TCVN 2098-1993<br /> Do bdng mang son 57% 60% 60% TCVN 2101-1993<br /> <br /> Kit qui d bang 2 cho thiy cle hdn hgp chit IV - KET LUAN<br /> ire che dua vao mang epoxy khdng Inh hudng<br /> ding ke din tfnh chit co If cita mang epoxy. Vi i. Hdn hgp CMP vl ZMCP cd kha nang tic<br /> vay cd the dua cae hdn hgp chit lic chi nay vIo chi an mdn thep CT3 trong dung dich NaCI 0,5<br /> mang epoxy nhim ning cao do ben chdng an M kha tdt.<br /> mdn cua nd ml khdng lam anh hudng din tfnh 2. Hdn hgp CMP vl ZMCP ed kha nang<br /> chit CO If. nang cao dd bin chdng an mdn thep CT3 cita<br /> 514<br /> mang son epoxy trong dung dich NaCI 0,5 M. 605-610 (2004).<br /> Hdn hgp CMP vl ZMCP khdng llm thay ddi 2. V. I. Pokhmurs'kyi, I. M. Zin', S. B. Lyon.<br /> nhiiu tfnh chat ca If cita mang epoxy. Materials science. Vol. 40 (3), 383 - 389<br /> 3. Cac hdn hgp lic e h i tren cd thi thay thay (2004).<br /> thi cle cha't tie c h i ddc hai nhu Cr, Pb... se dem<br /> 3. V. I. Pokhmurs'kyi, I. M. Zin', S. B. Lyon,<br /> lai nhiing lgi ich vi kinh te trong cdng nghiep vl<br /> M. C. Simmonds. Corrosion engineering,<br /> dan dung, tii dd cd thi xay dung qui trinh san<br /> xuit son chdng gi thin thien vdi mdi trudng. science and technology. Vol. 39(2) 167 -<br /> 173 (2004).<br /> TAI LIEU THAM KHAO 4. Adriana O. S. Leitea, Walney S. Araysjoa,<br /> . Isabel C.P. Margarit, Adriana N. Correiaa,<br /> 1. I. M. Zin', L. M. Bilyi, I. P. Gnyp, M. B. Pedro de Lima-Neto. J. Braz. Chem. Soc,<br /> Ratushna. Materials Science, Vol. 40 (5), Vol. 16 (4), 756 - 762 (2005).<br /> <br /> <br /> <br /> <br /> il5<br />