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Abstract As has been mentrtoned before.wate.r-solubl.e. its gained mOreiwportanco in recent yellrs after the world war II, due to their wirle p.pplication in j;;,cd.erncOIlWlunities. They are chara.0’ter5.E:n~d).ythe~r fast drying, ease of application and e1i:minat.ionof fire and healthhazaJ:’da. Epoxyresina have not been described amongthe watersoluble ;i.nd.uat:r-ievlehicles.Th5_s:isattributed to high fum~- tionality of the resin. However,epoxy resins can be watersolUbilized after redur:ing its functinality. The Lain techn~~ ues adapted in this investigation for producing watersoluble vehicles comprising epoxy resins, at least in the early stages of forLation are brieZly described as follows I The produced epoxy ester were subjected to either Daleinization, in case of cOj;;,pletelyde;t!unotionali$ed~poxy este~, OD reaction with poly-basic ~ei1 or anhydride in c~ of Partial estor. A- Maleinized Epote The Daleinization 1;echnj,quesuceess:fully applied on drying oUs was borrowedfor use in epoxy esters of: n~ oils fatty acids. (1) The first stage involves the preparation of completely esterified epoxyresins. This treatsent permits cQmp+,pe de:f:’unctionalization 01: the ::.’as.in. Trials were conducted for this purpose result, in the formation of P.. gel•-J.;iJl:me ateria.l.s. ~Tl order to eliminate the possibilit:y of gelation, it was thought desi~:bJ.e to use cata.:lys~sin the este:if’ication reaction. The type of catalyst, its concentration and temperature of reaction were the parameters which studied. Fromthe data obtained, it was able to cll”lRSifythe various catalysts according to their reactivity &I’l foLlows: Highly Reactive Catalysts I LithiW1b;rdrox~e, Zinc oxide & SocUumc~ bonate. Moderately R.eactiveOatalyst: Lead oxide. Wea.1dyReactive Oatalysts I Barium& OalciUlJhydroxides. ~2) The second stage involves maleinization of the completeJ.y defunctiona,lized epoxyresins. To produce suitable consistency adduct., it was necessary to incorporate drying oils prior to mal.einization. The following table illustrates four suitable vehicle fOrLu.latlons based on maleinized adducts. Formula No. • C J.cpoaition I II 15% Maleinized I,.O. J.5% ~1A~e.i.rlj_Iz:eodO./J.C. oils mixture (70330by wt.). ~55r- ;r’aleinized. J,.O.jepoxy ester. <311b;Twt». 15%Maleir,ed L.O./D.C.O./epQXYester (2:1:1 by wt). In IV Maleinization of’ the cor.:pletely defunctionaJ.ized. epoxy esters of linseed fatty acids .results in the fOJ:’{:.8:QioOf ll gel materials. This tendency weBel:U:dnatedby the incorporation of drylng oils prior to the I:aleinization step. The preAence of ep.o:llle;yster in such fo.t’I1Ulatiqpsgreatly improves their perl’OrIlaneesand filr.: durability. Although the presence nt D.C.O. improves the colour of the Var.n1shos, yet it causes a slight tackness of the dried fil~. The o~her e~ter.native r.:ethedfor producing water-soluble epoxy containing resin. consists of the followj.ng n.anuf’acturing stageB~ 1- Reduction of the functionality of epoxy resinsl This treatment pertJ..ts reduction of the fnnctiC’nalit1 of: the p~en.t epoxy resins frolii.6 to 3. The aLou•,:’;of L:.oncbasic acid used for the pa~’al defunctionalization was cal.cuJ.a1;edfror:..the ep0XYT:’’O’sin characteristics. 2- Alkyd cooking. The partially defunc-:;ionaJ.:i.zede.poxy ester p.roe;luced111 the preceding BT,~gewas cons~derp.d as the source of the polyhydric e.1..coholsin fort’Jl1at.ing resins sin..ilar to alkyds. Twobasic proced~.res were adapted for the i”ormatj.onof epoxy-modj.fied alkyds. The first involves the use of :tatty acids, while the second involves the use of the oil itself. Various resin forUllations covering a wide raD.f:1o.jfe exeeas hydroxyl conneana we1’Elcomputed using the average functionality method. The :tollowing table illustrats a sui,.. table wateoluble reFlin formuJ.ations. Formula No. Composition v • VI VII VIII IX 30% Excess OR epo:x;y-modi:fiedalkyd based on LJ’A & madeby fatty acid method. 20% Excess OR epoxy-modi:fied alkyd baaed en LFABe r.ade by fatty acio. method. 10% Excess 0H epoxy-mod.i:fiedaJ.kydbased on LJ’A. Be madeby fatty acid zr.ethod. 0% Excess OR ePOXY-Dodi:fiedalkyd. based (Xl LFA Be madeby ~atty acid method 30% J:!lY-cesOsR epoxy-modified. alkyd resin based on r,:n and produced by L:ionoglyceridemsthod. FiI.m;u].a nCe G ~ ~ p 0 sit ion x 30% Excess OH epoxy-r.;odi:eiedalkyd resUl. based on Loo.lD.e.c. (1:1 by wt.) pzoduced by monogl~ceride Ir.ethod. XI .30% Excess OH epoxy-r.;odi1’iedalkyd resizl, baaed on D.C.1P.A.and produced by Llonoglyoer~de method. 1s a matter of fact, the increase of the excess hydroxyl content leads to the fOrLation of resins of better fUm characteristics. For thie reason, the 30% excess qyd»oxyl resin containing dehydrated castor fay acids were, inc:j.ude4 aLlongthe forlations studied. The produced resin was then neutralized with a netralizing base such as triethylar.ine or a=onium hycl:’:’Qxide to pH8, followed by thinning with r.;orewater. Jl.ddition of eth,yl alcohol was necesslU’Yto red.uce the Viscosity of the aqueous solution to the workable consistency. The following table rer~sent,s the average composition. Resin 30% Wato,,r. .35-5.5% Ethyl a.lcohol .35-.’’”’./’% Water soluble vehicles based on maleinized edducts requiz-.d s10<U.lepr_1.l}ohocol ncentration than veh.telas baaed . .Jroolecula.w:oeight of tho l.”,t”’;er. The workwas extended to evaluate the select;ed vehicJ.e ~orIllU1aticns. The following gene.r.alization we.r.edrawn. 1- The oolC’ur of the vehicle depends on the presenoe D.C. chain, i.e. tuose containing high percentages exJU.be1; p~ar colour. 2- The viscosity of the aqueous solutions (the neutral1zel;\ .; ..- resins depends on pHof the cedilW. solid contet; as wel+ aJi the percent of aJ.cohol present. r ’fhe Presence of water-soluble driers is necessa;:y to shorten the drying tiJroeof these aqueous solutiqps. 4-M8Dganesea.”.etate was proved to be the Ir.ost eicienC; catalyst employedwhenused in aIllounts0.03%baon metal/resin. Higher drier conoentration leads ’l.io pre”i •. , .. ’ petation of the resin. 5- The gloss of the staved films are of higher veJ.ups +0:11 all types. The presence of epoxy ester in the res~ for1+iUJ.ation1opro79s the ha.rdness of the beked f:U.I;lB~ However,the presence of D.C.O. fatty chain in the resin forr.u1a reduces considerably the hardness due to their tailkne~s properties. COIr.pletefilL:..he.rdJ1esswas ache”(ld ~te.r baking for two hours at 200°0. 6- The presence of ep::’I’lteriwpr.ovesconsiderably the water, acid and aJ.•<al•.resistances of the dried fills. 7- All films of the tested resins pass satisfactory the flexibility and adhesion tepts. |