الفهرس 
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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.