To Improve the Dispersibility of Carbon Black in Water with Plasma and Organic Amines Treatments

Joumnal of Donghue University (Eng. Ed.) Vol.27, No.6 (2010)727To Improve the Dispersibility of Carbon Black in Water with Plasmaand Organic Amines TreatmentsCAO Shu-hua(曹淑华) , SHEN Li (沈丽), DAI Jin-jin (戴瑾瑾)*，DONG Zhi-jun(志军)Key Laboratory of Science & Techmology of Eco-Tetile , Mimistryof Education, Donghuo Univerity, Shanghai 201620. ChinaAbstract: Carbon black has been widely used in manygrafting* 0], surface oxidation.r), etc., to introduceindustrial areas, but it i poor dispersibility in water. Inpolar groups onto its surface. But most of the approachesorder to improve its dispersiblity in water, carbon black wasabove were conducted in aqucous condition, which wouldtreated by axygen plasma. Plasma treatment, as one of thelcad environmental pollution and require considerableenvirormental friendly methods, has been used to introduceenergy for post treatments such as drying.polar groups, mainly xygen-containing groups, 如thePlasma treatment, as one of theenvironmental friendlysurface of carbon black. The results show the dispersibilitymethods, has also ben used t如o introduce polar groups, mainlyof treated carbon black in watσr is greatly improved, whichoxygen-containing groups to the ourface strncture of carbonis expressed with the centrifugal and gravity settlementblack. The study of Takata et al. on plasma treatment ofrates. Analysis of the treated carbon black with X-raycarbon black indicated that the ratio of oxygen/carbonphotoelectron spectroscopy (XPS) indicates that xygenincreased with increasing treating time, and reached aplasma treatment can cause significant increase of polargroups includingC- -OH, 000H, C- O, andO -C-0onsaturatod valuc of 0. 42[3]. Park et al. reported that oxygcnthe surface of carbon black thus greatly improves thecontaining function group of carbon black was introduceddispersing stability of carboo black im watar. Besides, thethrough axygen plasma treatmen[4J. Li and Horita alsodispersibility of plasma treated carbon black can be furtherreported that oxygen containing function group on the surfaceimproved by the addition of organic amines, especiallyof carbon black increased ater an orxygen plasma treatmentil.polyetheramines. The improvenent of the dispersingIn this paper, xygen plasma was used to treat carbonstability of carbon black has also been conflrmed by etablack. The settlement ratcs of carbon powders treated underpotential measurements.different conditions were measured, and the infuence ofKey words: carbon black; axygenr; plasma; amines; X-raydifferent amincs was also studied. X-ray photoclectronphotoelectron spectroscopyspectroscopy (XPS) analysis shows the change of the surfaccac mumber; TS195. 13Doaument code: Astructure of carbon black after plasma treatment.Article ID; 1672 - 5220(2010)06- 0727- 05.1 ExperimentalIntroduction1.1 MaterialsThe materials in details were shown in Table 1.Carbon black has been widely used in many industrialareas, such as reinforcing filler of rubberl, conductiveTable 1 Materials in the experimentagent of plastics'), and black pigment for coating',MatcrialSourceinks), or tonef"], These applications all involve dispersingcarbon black into various media, e. g. water-borne or oil-Carbon black CommercialDegusa Co., Ltd.borme media. The quasi-graphitic structure, complexproductsOxygcn≥99.2%Shanghai Sangang-Messerconfigurations, and colloidal dimcnsions of pristine carbonGas Product Co,, Ltdblack result in poor dispersibility in a variety of medias.Organic amincs CommercialHuntsman Co. , Ltd.Inks are waterborne dispersions and have been widely uscdXTA-758in printing of paper or textils. In order to improve 谢Polyetheramine M. =1000,Huntsman Co, Ltd.dispersibility in water, carbon black has been subjected toL- 100HLB=17.0Polyetheramine M. =20,Huntsmnan Co. , Ltd.various surface treatments, for instance, surfactant surfaceL- 207HLB=13.8adsorptionf.n, encapnhation,surface chemical中国煤化工Reccived date; 2009-06 -30TMYHCNMHGFoundation item: Program for Changjiang Scholar and Innovative Rescarch Team in University, China (No. IRT0526)曲Correspondence should be addrestod to DAI Jin-jin, E-mail; jindai@dhu. edu. cn728Joumal of Donghu University (Eng. Ed.) Vol.27, No.6 (2010)(Table 1 cotinued)and pH of the upper suspension is measured using pH mcterE- 201-C (made in China). Zeta potcntial of the upperMaterialGradeSourcesuspension is mcasurcd using a Zetasizer Nano SericsPolyetheramine M. =3 0Huntsman Co, LId.(Malvern Instruments Ltd, UK).HLB=17.1Dicthanolamine ARSinopharm ChemicalRcagent Co., Ltd.2 Results and DiscussionNotc: HLB is hydrophilc-lipophile balance oumber.2.1 Eftects of plasma treatments on stspension1.2 Procedure and measurementstability o[ carbon black in water1.2.1 Plasma trealmentIn order to compare the stability o{ suspension ofPlasma trcatment equipment GPT- 3 RF 13. 56 MHzcarbon black before and after plasma trcatment, their(made in China) was used in this study. Put a petri dishgravity and centrifungal stability were dctermined and theloaded with the carbon black sample of about 100 mg asresults were shown in Figs. 1 and 2.thin as possible into the plasma chamber, and open thevacuum pump till the pressure reaches to about 10 Pa.Flush the chamber with oxygen for 2 -3 times, and then30}introduce oxygen into the reactor. Once the pressurercachcs 30 Pa. initiate the glow dischargc at a power of80 W for a trcatment time 5 min. After the plasmatrcatment, raise the pressure and remove the samples.I -Plsm uralme1- Untreated1.2.2 Measurencnts o{ sttlemneat ntes ol carbon black in2091.2.2.1 Ccntrifugal sttlement rate340Disperse the trcatcd or untreated carbon blackSubsidence time/dsamplc of about 1 g into 100 mL distiled water and stirFig.1 Gravity sttlement stability of oxygen plasmawith a high-speed mixer SFJ - 400 ( Shanghai Xiandaitrcated and untreated carbon blacks in waterEnvironment Engincering Technique Co., .Ltd.China) at1 800 r/min for 30 min. Pour 5 mL dispernion0pinto the centrifugal tube and centrifugc at 2 500 r/minfor a predctermined period of time using ccntrifugal80}machine 80-2 (Shanghai Medical Devicc Co.. Ltd.50China). Take out the upper part of the suspensioncarefully and dilute with distild water. Mcasure is0transmitance using a UV - 2102 DCS UV-Visspectrophotometer ( Unico Shanghai Instrument Co. ,201Ltd. , China) and calculate the dispersing efficiency.The dispersing eficiency (D. E.) is defined 2s°510i5202530D.E./% = (1-T)X100,Cerifogal time, minwhere T is the trasmittance. The higher the D. E. value, ,Fig.2 Centrifugal sability of oxygen plasma trcatedand uotrcated carbon blacks in waterthe morc stable the suspension of carbon black is.1.2.2.2 Gravity sttlement raleAs shown in Fg 1, due to the great tendency ofPrepare the same suspension in Section 1.2.2.1. Theasgregation of the particles, the suspension of the untreatcddispersion was then setled without any disturbance for acarbon black was casy to sttlc down in water whosc initialpredetermincd period of time. Take the upper part of theD.E. was 22%, and reduced to 0% after7 d. In contrast,suspension, dilutc properly, and quickly measure itthe D. E. of the trcated carbon black was 100%'at thetransmittance and calculate dispersing cfficiency as above.bginning and was still as high as 80% even after35 d. Figure1.2.3 XPS analysts2 showed the resuts of the centrifugal stability, which similarlyXPS measurcments were carried out by uring ahad scttled dowm totally中国煤化工me time the treatedVacum Generators ESCALAB 250 spectrometer and an AIafterK Alpha X-ray source (15 kV, 150 W).smpCNMHG78% ater25 nrin1.2.4 pH and zela potentiacentuiugauon. n was oonous Inar oxyen plasma treatmentPrepare the suspension according to Section 1.2.2.1,had dramaically improved the water dispening sability ofJoumal of Donghu University (Eng. Ed.) Vol.27, No.6 (2010) 729carbon black. Some polar groups must be inorporated ino the(Table 3 continsed)surface of carbon black after the plasma treatunent.UntrealedOxygen plasmu2.2 The surface chemical composition of carboncarbon blacktreated carboa blackblack after oxygen plasma treatmentC。COOH8.35%5.51%In order to obtain thc information of the changc in theC.C一0,0004.14%9. 12%surfacc composition of carbon black after plasma0。8.51%12.54%trcatment, XPS mcasurement was carricd out, and theFrom Table 2. the oxygen contcnt of carbon black wasresults were shown in Table 2. Curve fitings of the Coincreased from 8. 51% to 12.54% after the plasmaspectra of carbon black wcre shown in FPig. 3 and thetrealment. It mcant many polar oxygcn-containing groupsrelative intensitics wcrc summarizcd in Tablc 3.had been incorporated into the surface of carbon black.Table 2 Relative chemical composition and atomicthus the surface polarity had been grcatly improvcd. Theratio for carbon black treatcd by oxygcnmost noticcable was the increase of C-0, 0-C-0plasma measured by XPScontents from 4. 14% to 9. 12%，scen from Tablc 3, whichChemical compoition/% Atomic natio /%implicd the grcat increase of acidic groulps at the surfacc ofcarbon black.Na0/C2.3 Effect of polyetheramine L- 300 on waterControl91.418.510.09dispersing sability of the oxygen plasm tratedPlasma treated87.2112.540.260.14Polycthcramine L- 300 was added to the suspension of50 0000a)Cng-Ccarbon black and detcrmincd the dispersing stability again.The results were shown in Fig. 4. Because of the4000rcmarkable increasc of acidic group on the surfacc ofcarbon black after the plasma trcatmcnt, the dispersing3000 rCILCOHCNstability might be further improved by containing some2000 tpolyetheramins. It could be scen from Fig. 4, the additionC.c=0,0 c-0of polyetheramine improved the dispersing stabilitics ofC.COOH1000both trcated and untreated carbon blacks, but theimprovement of trcated sample was more apparcnt.294292290288286284282 28Binding energy/eV100p=25 00CIC -C30(6b0t8 1000十Treated carbon blaxck+L- 300CI.COHICN0}+ Untreated carbop black +L 300- Trated carbon black.10 00个C.C=oh5000 t20 25 30Centifugal time/ min2%6294292290288286284282280Fg.4 Ccntrifugal stability of untrcatcd and trcatedcarbon blacks with and without L- 300 amineFig3 Curve (tigt ol Cn spectra of carbon black(the weight concentaion was L- 300/with plasmai (n) trcated,《b) uptreatod(carbon black + watcr) = 5%)Table 3 Rclativc chemical composition detcrminedPolyectheramine L - 300 had an amino-group and a longby XPS for carbon black untrcated andhydrophilic molccular chain. The anchoring of thtreated with oxygen plasmapolyetheraminc. a weak alkaline. on the surface of treatedUatreatedOxygen plasmacarbu中国煤化工.the long hydrophiccarbon black treated carbon blackmole; dispersing stability ofC.C-C57.17%55.01%。 CN MH GeberonheCis COHCN21.75%17. 57%containing polar groups on the surfacc of untreated carbonJoumal of Donghu Uiversity (Eng. Ed.) Vol.27, No.6 (2010)O OHiHO.OHH2OCH,-(OCIH2CHR]- -{OCH:CH(CH)I- NH;H^ ~0o 0~N'H,- -(CH,)CHCH,Ol, -(CHRCH,0I- CH,o N"H,-(CH,)CHCH20l- -ICHRCH12O1- CH,1000~N'H-(CH,)CHCH2O],- HCHRCH2OL- -CH,个o .ooH 8Fig.5 Anchoring of amines o the surface of plasma treatod carbon black vi salt bondsblack than treated carbon black, this further explained whystability to the trcated carbon black,the polyetheramine L - 300 was effective for both treated00 %and untreated carbon blacks, and more effective for thetreated one.952.4 Effect of various amines on water dispersingx0 tstability of the oxygen plasma treated carbonblackExcept the polyetheramine L 300, other four- XT-758_|十Diethanolaunineamines, polyetheramine L- 100, L - 207, organic amine_ L- 300XTA- 758, and a small molecular amines diethanolamine+ L一100Controlwere tried. The resuts were shown in Fig. 6. Al fivesamincs had improved the water dispersing stability of the70152025 30trcated carbon black, and L- 300 was the best. CartbonCenrifugal timne/ minblack water dispcrsion of plasma treated stabilized withFig.6 Efccts of various amines on water dispersingL-300 had a D.E. value of 94% after subjected tostability of plasma treated carbon black (thecentrifugation for 25 min. Polyetheramine L - 100 havingweight concentration was amine/(carbonblack + water) =5%)relatively shorter chain length (M. = 1000) was sinilar toL- 300 in terms of its hydrophilicit (HLB=17.1), but its2.5 Effect of amine conceatration 0n the waterfunction for improving dispersion stability was noticeablydispersing stability of carbon blackinferior to L-300. This meant chain length was a quiteFor finding the optimum quantity of amine added inimportant factor here. L - 207 was also quite efficientthe dispersion, different amounts of L- 300 were tested.though it was more hydrophobicthan L- 300.Diethanolamine was the least effective because “isdispers中国煤化工x black improvedmolccular weight was only 105. It was interesting to note,until itH.CNMHG°concentration ofhowever, that. XTA- 758, an amine of a molecular weightabout 570，ana toenwun L uupuurc wumore amine wasas small as 132 performed very well in bringing dispersingused. Zeta potcntial analysis was prcsented in Table 4, .Joumal of Donghua University (Eng. Ed.) Vol.27, No.6 (2010) 731indicating that zeta potentials of the untrcatod carbon bluckwas only - 18. 39 mV, while that of plasma trcated sampleReferenceswas -27.49 mV, and could be higher than - 30 mV器more and more amincs were added. Obviously, surface[1] Doanet J B. Nano and Microcomposites of Polymerscharge increase had played a very important role here inElastomens and Their Reinforcemcnt [J]. ComporiesScience and Teclinology.2003, 63(8); 1085- 1088bringing stability to the dispersion. Morcover, zctapotential reached to a peak at the amine concentration of[2] Dai K, XuXB, Li Z M. lectrically Conductive CarbonBlack(CB) Flled in situ Micofibillar Poly ( ethyleneabout 5%，where a maximum stability had also beenterephthalac) (PETP)/Polyethylene(PE) Composite with aobserved in the stability tcsts. This may sggest that surfaceSelective CB Distributio [J]. Polymer, 2007, 48 (3);of the trcated carbon black had been sturatod with amine849 -859.moleculces at a concentration of about 5%.[3] Lw, XieZ M, Li Z M. Synthesis, Charcaterization ofPolyacrylate-gCarbon Black and Its Application to Soap-Froce Walerbome Coating []. Jounal of Applied PolymerScience, 2001, 81(5): 100- 1106.[4] BelmoatJ A, Adams C E. Non-aqucous Inks and CoatingsContaining Modified Carboo Products; US, 5713988[P].1998.[5] JoG R, Hoahino K, Kitamurn T. Toner Display Based nParticle Movemeots []. Chemistry of Materials, 2002, 140t(2); 664- 669.[6] Dossoleti L. Ricoei R. The Adsorption of PolystyreneSulfonate and Ethoxylated Non-ionic Surfacetant at CarbonBlack Water Interface [J]. Dispersion Science and705o15202530Techinology, 1995, 16(3/4); 205 - 220.Centrifugal time/ min[7] Lin Y N, Smith T W, Alcxandridis P. Adsorption of aFig.7 Dispersing stability of treated carbon black atRake-Type Siloxane Surfactant onto Carbon Blackdifferent amine conccatration (tho weightNanoparticles Disperscd in Aqucous Mcdia[]. Langmuir,coceatration is defined够amin/(carbon black +2002, 18(16); 6147- 6158.water); aminc i L- 300 polycthoraminc)[8] Tiarks F, LandCester K, Antonicti M. Encapoulatioa ofTable 4 Zcta potentials of carbon blacksCartbon Black by Miniecmulsion Polymerization [J].Macromolecular Chemisury and Physics, 2001, 202(1); 51 -SamplesZeta potential /mV pH56.[9] Zhou J, Xu FM, Zhou WL. et al. Chemical ModificationUntrentod carbon black- 18.397.3of Carbon Black Surface and Its Didpersibility UJ]. JournalTroatod carbon black-27.49.8of Nanjing University of Science and Technology, 2006, 30Treatod carbon black +1% L- 300-28.42(6). ?78- 782. (in Chinese)Trcated carbon black +3% L - 300-31.38.2[10] ZhaoJ Y, WangC Y, Li T Q. Grafting of HyrophilicTreated carbonblack + 5% L- 300- 82.76.5Polymer on Carbon Black under Ultra Sonic IradiationTreated carbon black +7% L- 300-31.669.8.[J]. New Carbon Materials, 2005, 20(4); 329 - 334. (inTrated carbon black + 10% L-300-31.85Chincse)[11] YinXL. Wang H Y. Modification of Carbon BlackSurface by Ozone[J]. Hebei Chemical Dngineering and3 ConclusionsIndustry, 2006, 29(8); 17 - 19. (in Chinese)[12] ZhaoJ Y, WangCY, Shi ZQ, ebal. Surface OxidationPlasma trcatment qf only 5 min could bringand Grafing of Carbon Black [J]. Journal of Tianjinsignificantly improvement to dispersing 'stability ofUnireriy, 2006, 39(1); 49- 52. (in Chinese)carbon black in wator. XPS analysis indicated the.. [18] Takada T, Nakahara, Kumgai H, et al. Surface .Modification and Characterization of Carbon Black withoxygen content of carbon black Wa increased fromOxygen Pasa []. Carbon, 16, 34(9); 1087- 1091.8.51% to 12.54% after the plasma treatment. Thedispersing stability of the trcated carbon blacks could be[14] PurkSJ, Cho KS, Ryu S K. Fller Blastomer lnteractions:Influcncc of Oxygen Plasma Treatment on Surface andfurther improved via the addition of various organicamines, and among which L-300 was the best in中国烤化工1442.°lack/Rubber Compoitcsimpartingdispecrsingstability. Theoptimum[1s]C N MH Gal Characerization ofconcentration of L-300 was 5%, at which the highestuarooa Back suojeucu“r uxygen Plasma [J]. Carbon,value of zeta potential had also been observed.2000, 38(1); 133- 138.