Note: Descriptions are shown in the official language in which they were submitted.
CA 02256529 1998-11-26
H 1867 PCT
31.0~.1996
A Cyanoa~ "l~te Adhesive
This invention retates to a cyanoa~late adhesive CGI ~tai. ,iny an ester
as pl~s~ ; An
Cyd"odaylate adl,esives containing an ester as p'~tic;~er are known.
Thus according to DE 34 00 577 up to 25% by weight of a pl~s(ic-;~Qr are
5 added in additio" to 4 to 30% by wai~l It of a copolymer of vinyl chloride andvinyl ~oet~e. The pl li~ r in ~ ~Pstion is an ester of an dr~.",alic mono- or
dicarboxylic acid and a mono- or polyhydroxy ~",~,ound. Appart:nlly the
rate at which the adhesive cures is not siy. li~iCdl Itly a~reclecl by the addition
of this aromatic pl-slio;~er nor is the quality of the bond fo,l,~ed during the
10 curing pn~cess. When these tests were re-run, however it was found that the
curing rate was siy,)ificd, Itly re~ ~c~ Thus the setting rate of cyanoacrylate
ethyl ester for example on EPDM is slowed down from 5 seconds to 35
seconds by a 30% addition of butyl benzyl phthalate
In A~L l~t;vn ac~rdin~ to DE 43 17 886, the following esters are added
15 to cyanoacrylate adhesives to reduce adhesion to the skin:
1. AliphdtiC Cdl L~ylic acid esters co, Itai"i"y an alipl ,atic group in which
6 or more Cdl bon atoms are directly attached to one another
2. AIi~Jhdt;C cdlL~tylic acid esters containing at least two aliphatic groups
in which 4 or more carbon atoms are directly atlact ,ed to one anotl ,er
20 3. Carboxylic acid esters of a ~, L ocyclic ~ ound which in a carbox-
ylic add residue or an alcohol residue c~nlains an ali~JI ,atic group inwhich 5 or more ca~ L,on atoms are directly dtla~,e.i to one anothen
In ~dLI;lir~" the cya-,odaylate adl~sives contain poly~eri~atiol~ accelerators~
The problem add~essed by the p~esenl invention was to avoid the
25 diadvantages of known cydllod~ylate adl ,esives containing pl slic;~ers and
more particularly to provide a cyanoacr~late adhesive having high stability
in storage useful slre, l~tl ~ values and virtually the same setting rate.
CA 02256529 1998-11-26
H 1867 PCT 2
The solution provided by the invention is clefi.-~J in the claims and
consists ~cs~"tially in using at least one partial and/or full ester of a
m~,,.ob-~ri~ or ~oly:~sio aliphatic ~.L~.<ylic acid containing 1 to 5 ca.Lo.~
atoms directly dtla~l-oJ to one a-,-~U.er and ~.-onol,~rdric to pa,~tahydric
aliphatic al~l-ols containing 1 to 5 ~-I,G.I atoms directly dtla~eJ to one
another as pl~ r, the number of ~- L G-~ atoms directly atlacl)ed to one
another in the other aliphdtic groups being at most 3 where one aliphalic
group contains 4 or 5 ~-L,o-, atoms directly dua~ J to one an~tl.er.
The alcohol ~"po,)e,~t of the ester is pr~fe,~ly an alcohol ~ntai,ling
1 to S and, more particularly, 2 to 4 OH groups and up to 2 to 5 and, more
particularly, 3 or 4 ~,bon atoms directly dtlached to one a".~tl,dr. The
number of carbon atoms not directly atla~ hed to one a,)otl,er may be as high
as 1 10 and, more particularly, is up to 18 ~, bo, ~ atoms.
The following are ."e,ltio-.eJ as examples of monohydric alcohols:
methanol, ~ll ,anol, 1 -~rDpd, ~ol, 2-~,. opanol, 1 -butanol, 2-butanol, 2,2-
dimethyl-1~opa-,ol, 2~ethyl~ ,a"ol, 2,2-dimethyl-1-~,r~a"ol, 2 rnethyl-
2-propanol, 2-methyl-1-butanol, 3 rnethyl-1-butanol, 2-methyl-2-butanol,
methyl-2-butanol, 1-~entanol, 2-pe"tanol, 3-~ntanol, c~clopen~al lol,
cyclopenlcnol, glycidol, tetrahydrofurfuryl alcol ,ol, tetrahydro-2H-pyran~-ol,
2-methyl-3-buten-2-ol, 3 rnethyl-2-buten-2-ol, 3-methyl-3-buten-2-o1, 1-
cyclupropyl etl,anol, 1~enten-3-ol, 3~,1t~n-2-ol, 4-~"ton-1-ol, 4-penten-2-
ol, 3-pentin-1-ol, 4-pentin-1-ol, ~ aryyl alcol,ol, allyl alcohol, hydroxyace
tone, 2-methyl-3-butin-2-ol.
The following are ~,entio"eJ as examples of dihyd~ic alcohols:
ethane-1,2-diol, prop~ne-1,2~iol, propan~1,~diol, dihydroxyacetor,e,
thioglycerol, 2-methyl 1~,opan~1,3 diol, 2-butin~1,4-diol, 3-buten~1,2~iol,
butane-2,3-diol, butane-1,4-diol, butane-1,3-diol, butane-1,2-diol, 2-butene-
- 1,4-diol, 1,2~clope"ta"ediol, ~methyl butan~1,~diol, 2,2-di",etl"~l
propane-1,3-diol, 4-cyclopenten~1,3-diol, cycJupe,lta,~1,2-diol, 2,2~Jil"ethyl
propane-1,3-diol, p~nta"~1,2~iol, pellt~ne-2,4~iol, ~ tall~1,~diol, 4-
CA 02256529 1998-11-26
H 1867 PCT 3
cyclop~- ~t~n~1 ,3-diol, 2-methylene ~,r~pane-1 ,3-diol, 2,3-dihydroxy-1,~
dioxa--e, 2,~dihydroxy-1,~dithiane.
The followin~ are ,.,e.~ti~...ed as examples of trihydric alcohols:
glycerol, erythrulose, butan~1,2,4triol, erythrose, U,reGs~, t~i."eU"~lol
5 ethane, 2-hydroxymethyl propane-1,3-diol.
The followin~ are m~-ltio..~J as exsmples of tetrahydric alcohols:
erythritol, Ihreilol, pentaerythritol, ~r~ 1O5¢, ribose, xylose, ribulose,
xylulose, Iyxose, sscorbic acid, ~luconic acid-y~ tone.
The following are ,ne.~tioneJ as exa--,ples of pa..t~l.y~l~ic alcohols:
10 arabitol, adonitol, xylitol.
In one particular e~ ~nl of the invention, the polyhydric alcohols
described above may be used in etl,eri~,ed form. The ethers may be
prepared from the alcohols ~ Itioned above, for example by ccnde"sation
reactions, Williamson's ether synthesis or by redction with alkylene oxides,
15 such as ethylene, propylene or butylene oxide. Examples include diethylene
glycol, triethylene glycol, polyethylene glycol, diglycerol, triglycerol,
tetraglycerol, pentaglycerol, polyglycerol, technical mixtures of the conde"-
sation products of glycerol, glycerol propoAylate, diglyc~rol ,,,upoAylate,
pentaerythritol ethoxylate, dipentaerythritol, ethylene glycol ~"o- ~obutyl ether,
20 propylene glycol monohexyl ether, butyl diglycol, dipropylene glycol
monomethyl ether.
The following monoL~ic carboxylic acids may be used for the
este, ification reaction with the alcohols mentioned above: formic acid, acrylicacid, acetic acid, ~ opiu,-ic acid, butyric acid, isobutyric acid, valeric acid,25 isovaleric acid, 2-oxovaleric acid, 3-oxovaleric acid, pivalic acid, aceto~tic
acid, levulinic acid, ~methyl-2-oxobutyric acid, propiolic acid,
tetrahydrofuran-2~a~Loxy1ic acid, ."ethoxyacetic acid, dimethoxyacetic acid,
2-(2-methoxyethoxy)-acetic acid, 2-methyl acetic acid, pyruvic acid, 2-
methoxyethanol, vinyl acetic acid, allyl acetic acid, 2-pelllelloic acid, 3-
30 pentenoic acid, tetrahydrofuran-2~, L oxylic acid.
CA 02256529 1998-11-26
H 1867 PCT 4
The following are examples of polybasic carboxylic acids: oxalic
acid, malonic add, fumaric add, maleic add, succinic add, glutaric acid,
acetylene dic~ ylic acid, ~ cstic acid, aceto,)e dicarboxylic acid,
",eso~-~'ic acid, ~tta~nic acid, dimethyl malonic add, methyl ",alo"ic acid,
5 ethyl malonic add,
Hydroxycarboxylic acid~ may also be used as sta,li"~ ",ate,ials,
examples including tartronic acid, lactic acid, malic acid, talldlic acid,
citra",aleic acid, 2-hydroxyvaleric acid, 3-hydroxyvaleric acid, ~hydroxybu-
tyric acid, 3-hydroxyglutaric acid, dihydrox~fumaric acid, 2,2~i",ell,yl-3-
10 hydrox~propionic acid, cJi.ll~UIylol propionic acid, glycolic acid
The esle, ification may be either complete or partial. Mixtures of theseacids may also be used for the eslerir,caliG".
The esters to be used in ac~l J~"ce with the invention as prepared
from these alwhols and cal L~xylic acids or the c~ ~spo"di.)g derivatives are
5 preferably free from catalysts, more particularly alkali metals and amines
The following are mentio"ed as examples of the esters according to
the invenffon: glycerol ~ jA~ Q, glycerol tripropionate, tri~lycerol p~utaace-
tate, polyglycerol A~tPle, diethylene glycol di~c~tAte, 3-hydroxyvaleric acid
ethyl ester, lactic acid butyl ester, lactic acid isobutyl ester, 3-hydroxybutyric
20 acid ethyl ester, oxalic acid diethyl ester""eso~Alic acid diethyl ester, malic
acid dimethyl ester, malic acid diiso~topyl ester, tall~l ic acid diethyl ester,tartaric acid dipropyl ester, tartaric diisopropyl ester, glutaric ester dimethyl
ester, succinic acid di",etl,yl ester, succinic acid diethyl ester, maleic acid
diethyl ester, fumaric acid diethyl ester, malonic acid diethyl ester, acrylic
25 acid-2-hydroxyethyl ester, 3-oxovaleric acid methyl ester, glycerol d~cetAte,glycerol tributyrate, glycerol tripropionate, glycerol cJi,u,opio,)ate, glyceroltriisobutyrate, glyoerol diisobutyrate, glycidyl butyrate, Acetoac~tic acid butyl
ester, levulinic acid ethyl ester, ~hydroxyglutaric acid ~l;,ll~thyl ester, glycerol
acetate Ji~,opionate, glycerol di-cet~te butyrate, propiolic acid butyl ester,
30 propylene glycol diaoetate, propylene glycol dibutyrate, diethy.ene glycol
CA 02256529 1998-11-26
- H 1867 PCT 5
dibutyrate, l~im~ll,ylol cU.a.~e bi~t~f-, t imaU,ylol ~U,ane tributyrate,
,~p~, tyl alcohol dibutyrate, n~Un~ rao~tic acid pentyl ester, dim~U ,oxyac~
tic acid butyl ester, glycolic acid butyl ester.
The boiling point of the esters accor~in~ to the invention is above
S 180~C and ~r~rably above 200~C at oG--"al pressure.
The estors according to the invention are added in a quantity of up to
50% by weight and ,~,efcrably in a quantity of 1 to 30% by weight, based on
the adhesive as a whole. Beyond a co-,~-lbdtion of 30% by weight and,
more particularly, 40% by weight, the polycyd"oa~ylates show ~ntacl-
10 adhesive prope,lies.
The cyanoacrylate adhesives are Essentially based on typicalmonoacrylic acid esters and/or bis~yanoauylates.
~ Typical ",onocyanoacrylic acid esters~ in the contexl of the present
invention are co""~ounds CGIleSpGlldill9 to the following general formula:
H2C = C(CN)-C0-O-R (I)
where R is an alkyl, alkenyl, cycloalkyl, aryl, alkoxyalkyl, aralkyl or haloalkyl
group, more particularly a methyl, ethyl, n-propyl, iso~,ropyl, n-butyl, isobutyl,
20 pentyl, hexyl, allyl, methallyl, uotyl, ~r~pdryyl~ cyclol,exyl, benzyl, phenyl,
aesyl, 2-chloroethyl, ~chlor~propyl, 2-chlorobutyl, trifluoroetl,yl, 2-methoxy-
ethyl, 3-methoxybutyl and 2-ethoxyethyl group. The cyanoacrylates
mentioned above are known to the expert on adhesives, cf. Ullmann's
Encyclopaedla of Industrial Chemistry, Vol. A1. page 240, Verlag
2~ Chemie, Weinheim (1985), US-PS 3,254,111 and US-PS 3,6C~,3~Q.
Prefe"ed ."GnG",er~ are the allyl, methoxyethyl, ethoxyethyl, methyl, ethyl,
propyl, iso~,r~p)~l or butyl esters of 2 cydnoac, ylic acid.
~ Bis-cyanoacrylates~ in the col)text of the pres~-,l invention are
compounds CGI ,esl~onding to the following ge"erdl formula:
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H 1867 PCT 6
lH2C = C(CN)-CO-OLR' (Il)
where R' is a linear or ~ ~ ~1 dif~l ~ ~l alkane group CGI Itai.ling 2 to 18
and more partieularly 6 to 12 C811~ll atoms whieh may also conlai-, hetero
5 atoms, sueh as halogens and oxygen, or ali~l,atie or a~o",alie rings.
However R' is ~,rererdbly a pure hyJ~a,bon.
It is i,.,~G-lant for the bis-ey~,-oa~lates to be partieularly pure. This
requirei",ent is satisfied for example, by the following pro~ ion and
purifieation ",etl,ocls. ~sse,ltially ~,.G"oe~ai"oa~lates are transesterified
10 with diols and the reaetion mixtures are then worked up by hacliG"al
erystallization.
Aceo(dingly a suitable pr~cess for the prod~ion of bis-eyanoaery-
lates co",~rises t,~nsesleril~ing 2-eya"oa~ylie aeid or alkyl esters thereof
eorresponding to the following ~aner~l formula:
H2C = C(CN)-CO-O-R2 (111)
where RZ is a linear or b,ar,cl ~cJ alkyl radieal co"laining 1 to 6 ~, bo" atomswith diols ~" t7spo"~i"y to the following yei ,eral formula:
[H~]2R' (IV)
where R' is a linear or ~ J ~d difi "c1ional alkane group co"tai. ~ing 2 to 18
~, bon atoms whieh may also eontain hetero atoms sueh as halogens and
2~ oxygen or aliphatie or ~ro",atie rings,
to form bis-eyanoaerylates co"_sponcJi"y to g~llerdl formula ll and then
purifying the reaetion mixture by hacti~,"al eryst~ tion.
Accordingly one sta, ling produet is monofi" lOtiGI ,al Cy8~ ,oa~ ylie aeid
or alkyl esters U~r~of c~l,es~"ding to formula lll. The alkyl group has to be
30 selected so that the alcohol fo",)eul is easy to remove. Suitable possibilities
CA 02256529 1998-11-26
H 1867 PCT 7
in this regard are known to the expert from the y~ ral b~..s~sl~lifi~tiu-l
rea~tion. The alcohol is ~rvf~.~biy r~-llo~od by ~i~t~ Qn. Accordingly, R2
is a linear or bra-,~l,eJ alcol-ol r~s~due conbining 1 to 6 ~IbGll atoms and
,u,e~rdbly 1 or2 c~,Lon atoms. The monofun~tiunal cya..oa~ylic acid ester
5 is sPhili~s~l in the usual way.
The diols (formula IV) are dihydric ,uri--.a~y or secc"Ja,y alcohols,
preferably ~ri,n."y alcol,ols. The hydroxyl groups may be in any ~,osilion to
one another, but are ~r~fer~Lly in the alpha/o")eya f~sition. The diols
co"tain 2 to 18 carbon atoms and p,efe~bly 6 to 12 carbon atoms. They may
10 be linear, branched or cyclic. The aliphatic radical may also contain an
aromatic group or, in addition to the hyd~og~" and ca,L,o" atoms, may also
co"lai.) hetero atoms, for example chlorine or oxygen atoms, ~,ref~rdbly in the
form of polyethylene or polypropylene glycol units. Hexanediol, octanediol,
decanediol and d~Jdec~ ~ediol are specifically mentioned as diols.
The cyanoaaylic acid ester is used in exc~ss Accordi"gly, the molar
ratio of monofu~,lional cyanoacrylic acid ester to the diol is at least 2.0:1.0,preferably 2.5:1.0 and, more ~refer~bly, 2.2:1Ø
The transeste, if icaliG" is catalyzed by strong acids, more partic,ularly
by sulfonic acids, ~r~ferably by d,un)dlic sulfonic acids, for example p-toluenesulfonic acid. However" a~l ~U ~alene suhfonic acid and bel ,~e,)e sulfonic acidand acidic ion excl,a"ger~ may also be used. The cc"centldlion of the
transesterification catalyst should be between 1 and 20 % by weight, based
on the monofunctional cyanoa~ylate.
The tra"ses~erificaliul"eacti~n is ca"ied out - as usual - in solution.
25 The solvents used are ar~,",dlic hyd~oc~GI~s and halo~enaled hydlucar-
bons. Prefel,ed solvents are toluene and xylene. The co"cen~ralion of the
solution is in the range from 10 to 50% and pre~rably in the range from 10
to 20%.
The r, ~nol ,ydric alcohol f~"lled and the water fol ",~.1 are removed in
30 known ,nar")er, ~l~ld~ly being ~istilled offwith the solvent. The conversion
CA 02256529 1998-11-26
H 1867 PCT 8
of the b ~ns~sts~,cdli~, f~;tion is ."u"itor~d. for examp.e, by NMR sp~a.
As usual the r~action Iasts several hours. Where toluene is used as the
solvent and p-toluene sulfonic acid as the catalyst the l ~actiur, is over after10 to 15 hours i.e. there is no further elimination of alcohûl.
S Now the way in which the redctiGn mixture is worked up is very
illl~lldl~t. Where acidic ion e~ n~6(s are used as the catalyst they may
be removed by simple fill~alion. Where soluble suHonic acids for example
p-toluene suHonic acid, are used as the catalyst they are removed by solvent
su hstitl ~tion: toluene is replaced by a mixture of I ,exane, I ,~ptane or ~eca"e.
After two r,aclio,)al crystalli aliûlls pure bis-cyanoa~ylate is obtained.
According to NMR spectra it has a purity of more than 99%.
The bis-cyanoa~ylate obtai,)ed is stable in slor~ye with the usual
st~hili7ers and in the usual conce, It~dtiGI ,s i.e. there is hardly any c~ ,dnye in
its melting point after 6 Illontl,s at 20~C.
However the bis~yanoa~ylates obta,"e.l pol~",e,i~e very quickly in
the presence of bases ~,referably almost as quickly as the colles~,G"diny
",onocyanoacrylates. As in the case of the monofu- ,~tio- ,al cyanoa~ylates
traces of water are sutricieilt for this purpose. A three din,e-,siû,,ally
crosslinked polymerwith relativelygood ll,en~al ~,upe,lies isformed.
Acoording to the invention tl ~ref~,e it is used in known cyanoa~ylate
adhesives in a quantity of O.S to 50% by weight pre~rdbly in a quantity of 1
to 10% by weight and more prbfer&bly in a quantity of 2 to ~% by weight
based on the adhesive as a whole.
~esides the pl--stic;~qr acoor~ling to the invention the adl,esive may
2~ contain other additives for example other pl-~tiçi~ers, thickeners stabilizers
activators dyes and ~c~leratura for example polyethylene glycol or
cyclodexl. i".
The adl ~sive is ~ parecJ in the usual way by mixing the co, "po"enls.
In all the cases invesliyate-L the new adhesives were stable in slora~e for
more than one year at room te",peral.Jre or for more than ten days at 80~C.
CA 02256529 1998-11-26
H 1867 PCT 9
The curing rate is hardly arr.s~,laJ by the pl '~ti~ . a according to the
invention, in other words it is prd~ra~ly not ~ouhl~ l and barely ~c~e~
minute in the case of EPDM.
The new cyanoauylate ~JI,esive according to the invention is
5 particularly suitable for the bondin~ of - in particular - rubber, metals, wood,
c~r~-"ics, china, pap~,~oar~, paper, cork and pl~~tics except PE, PP and
Teflon and Styropor.
The invention is ill~.sllatecl by the following El~a",,les
In order to obtain as cc ",~ he,)si~e an overview of the cl,anges in the
10 properties of the g,a"oa~ ~/lates brought about by the addition of plasticizers
according to the invention, mixtures of h~si~lly st~hili~ed pure ester and
glycerol triacetate (triacetin) in the range from 0 to 50% by weight were
prepared. The basic stabili~tion consists of hydroquinone (400 to 1,000
ppm) and SO2 (5 to 15 ppm). The samples were hGIIIO9enj ed for six days
15 in a shaking machine and then measured.
Examples 1 to 3
The results (viscosity, setting times, sll t "~U ,s) for the three different
esters AE, BE and MOE (AE = ethyl ester, BE = butyl ester, MOE = methoxy-
20 ethyl ester) are set out in Tables 1 to 3.
CA 02256529 1998-11-26
o
~D
UJ ~
~ ~ ~ 5 ~ N ~--
-- ' .. ~ O CD ¢~ ~
~ E a~
Z
o U~ ~ _ 0 0
g ~ 't ~ N ~ N
CO
O o O O O
E i-- ~, E ~ ~ ~ ~ ~OD ~o
.' Cl~ ~
N ~ ~ U)
._
3, o ~' CD a~ _ ~ 0
a~ 8 w _
c .a~ E
~ ~ C~
N t'~
~ _
- ' ae . o ~o ~o ~o ~o
a
a~
c~ ~ ~
~ _ ~n 6 6 ~: 6 ~ 6
~D o O U,~
_ 6 cn
~ o ~ ~ o ~5 ~ 8 ~ o
~ .. ~D
~ ~ E
0 ,~ X
CA 02256529 1998-11-26
H1867PCT 11
Accordinçl to Table 1, the ~ J;tion of the ~ r according to the
invention pr~ces a slight i~ r6ase in the ViSC05iti95. Accordingly, the
visoosilies of the ~lr-it;c;~er-containing s~ les are slightly higher after the
short-time sIora~a test (10 days/80~C in PE bottles).
lt is only with an ~ tion of 40% that there is a sli~ht increase in the
setting time on EPDM, but a ~istinct ;n~;r~ase in the setli. ~~ time on Limba.
By w nIrast, the ~ddition of pl~lic;-~r does not have any adverse effect on
the setting times on PVC.
The sl~"~tl ,s on aluminium only begin to fall with a pl~lic;~er co"tent
of 30%; the same applies to the sl,~r,~tl,s on PVC.
H 1867 PCT 12
Tabl~ 2: Influence of the Pl~sti~i7er Triacetin on the Viscosity, Setting Times and St~el,y~l,s of the Bu~yl Ester of
Cyanoacrylic Acid
ExampleAddition Ester Quantity Viscosity Setting Times 5~
1%1 ImPasl Isl INlmm21
1 Od/80~C EPDM Limba PVC Alu PVC
2a None BE 3.2 6.2 5 >60 <5 9.5 3.7
2b Triacetin BE 10 3.4 6.9 7 ~60 <5 8.4 3.4 D
2c Tr;ac~ti~ BE 20 4.0 9.1 10 ~60 <5 4.7 3.0
2d Tliacetil~ BE 30 5.0 15.9 13 ~60 <5 2.9 2.8
2e Triac~ti" BE 40 6.0 53.7 22 ~60 c5 1.2 1.9
2f Triac~ti" BE 50 8.2 87.7 90 ~60 c5 1.6 1.0
CA 02256529 1998-11-26
H 1867 PCT t3
Acco.cl;"~ to Table 2, the Z~ ;t;G.I of pl~s(ic;~ar also leads to an
in~ease in viscosit~ in the case of the butyl ester, although this i.,~rease is
more pronounced than in the case of the ethyl ester after the short-time
s~o,dye test, particularly in the case of the mixtures co, Itaining 40 and 50%.
Above 40% ~I-sli.,i-er, the selli..~,~ times on EPDM are no longer
~pt~le for a reactive ~-JI ~sive. Di~er~. .c~s in the setting times on limba
wood attribLnable to different ~l -- lie;-~r cc, Ite~nts were not in evids. .ce in view
of the long setting time of the pure ester. The setting times on PVC are not
adversely a~cte.l by the plaslic;~er.
The co",pa, atively low ~b e, ~~U ,s on aluminium and PVC in the case of
the butyl ester were further red~ ~c~rl by the addition of pl--tici~er. However,they are still acce~,table for a colltd~l adhesive above 20% and 30%,
respectively.
S 0 0 09< 09< 0 6 8Z 91 1 OS 30W U!l~e! 'l ~~
~ 0 0I-S 09~ 08 ~ SZ ~ 01 0~ 30W 'J!l~e!'l e~ D
1 0 1 0I-S OS SI L 9Z Z 6 0~ 30W U!l~e!)l P~ -~
Z ~-~ 0~-S St~ 8 S LZ v 8 OZ 30W 'J!lE~e!'l ~8
~ ~ 8-9 0I-S SZ 8 1 9Z L-L 01 30W U!~ q~
lWY9-~ 1 ZI 0I-S 0~ L S 88 1~L - 30W euoN B~
~)/\d nl~d eqw!l Wad3 ~oO8/PO I
Irww/NI lsl Isedwl 1%1
41BueJls sew!lBU!lleS ~ S~!~S!~ ~4!1Uen~ ~elS3 UO!l!pp~ eldwsx3
(30W) JelS3 l~41e~X~~;13
P!~~ ~!l~oeoue~ ~o s~llfiueJls pue saw!l fiU!ll~ l!soeS!~ e41 uo U!leoe!Jl Jb~e!ls~lJ e41 ~o eouenl~ul :~ elqel
d L981 H
CA 02256529 1998-11-26
H 1867 PCT 15
ACCGI I~ U to Table 3, the A~ ;OI I of the ~ lic;~r according to ths
invention also pro~l ~s a sli~ht in~ eas~ in the visc~ities in the case of the
MOE afflou~h, in c~ ~sl to AE and BE, the short-time stability in slor~ye is
slightly improved by the pl~ ;-er.
With a pl --lirl~r c~nt~ It above 40%, the settin~ times on EPDM and
limba are too lon~ for a reactive a~ sive. The settin~ time on PVC
inweases ~ sli~lly above 50%.
Wlth a pl ~ r conl~- n above 20% and, more particularly, 30%, the
slrenytl ,s on aluminium and PVC are at the level of a c~ntact adhesive.
Summary of Examples 1 to 3
With all three esters, the pl~ er bia~ti,) shows very good
c),a"od~ylate com~ coupled with high stability in storage in quantities
of up to 50% by weight.
Whereas the setling times on limba and EPDM only inc,rease beyond
a pl~sli~r content of 40%, sl, e, IyU ,s are re~uc~rl by plaslici er contents of20% (BE, MOE) and 30% (AE), but are still at the level of contact adhesives.
Examples 4 to 6
The influence of pl~slici~er~ on the impact sl,e"yl~l and moisture
resistance of the various c),a"oa~ ylates is illusl, ~led in Tables 4 to 6.
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H1867PCT 16
Table 4: Influence of the rl~-s~ic.; ~r T iaceli" on the 51 ,e,a,/l""~ Stre
of the Ethyl Ester
Example Addition Ester Quantity Sl,ed,/l",~acl St~e"gtl,
[%] lCJ/ClTt2l
(Steel Cube)
4a None AE - 18.5
4b Triaceti" AE 10 23.6
4c Triacetin AE 20 24.8
4d T~ia~tin AE 30 26.5
In the case of the ethyl ester (see Table 4) the ~- ~rlitiGn of pl~slic;-er
leads to an i"a~ase in impact sb~"~U" i.e. the aJl~sive bond beco-"es more
elastic.
The butyl ester ( cc Table 5) shows a similar result to the ethyl ester.
15 The impact slre"~tl~ which in the case of the pure ester, is d;slin~Aly abovethat of the ethyl ester in view of the greater chain length is further improved
by the addition of triacetin.
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H 1867 PCT ~7
Table 5: Influence of ~e pl~s~; ar T~ tin on the Sl -e~ "~a~t St~
of ~e Butyl Ester
Example AdditionEster Quantity Sl,ea-/l",~acl Sbell~tl
l lcJ/~]
(Steel Cube)
5a None BE - 30.4
5b Triacetin BE 10 32.0
5c Tl iaceti" BE 20 33.0
5d Triacetin BE 30 33.2
5e Triacetin BE 40 Not Measured
5f Tliaoelin BE 50 Not measured
In the case of the MOE (see Table 6) the ~-J- Iilion of l, iacetin leads to
a distinct inuease in impact st,e"~U,.
Table 6: Influenoe of the Plaslici ~er Tl iaceti" on the Impact St,e, l~l h of the
Ethyl Ester
Example AdditionEster Quantity Shear/lmpact Sllellyll
[%] [Ncrn/cm~]
(Steel Cube)
6a None MOE - 27.2
6b Triaceti., MOE 10 39.2
6c Triacetin MOE 20 44.3
6d Tl iaceli" MOE 30 48.8
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H 1867 PCT 18
Summary of test~ 1 to 6
The viscosity and stability in s~~ e of the ethvl ester is not adversely
~nr_~J by the addition of up to 50g6 by weight of the ~ r L ia~tin. the
setting times on EPDM and PVC are not si~,)ifi~"U~ i"or~ased either. Only
the setting times on limba are lor~er than 60 sec~ ,~s for a pl ~-lic-;-er conte"t
of 40% with no added accelerator. The aben~Jtll values on aluminium and
PVC fall to the level of c~ ~A ~JI ~sives above a rl ~ ;-er c~nten~ of 30%.
The bonds b~o",e i"oreasi. "~Iy more 6~
The inco,~,dtion of ~iao~in in the butvl ester leads overall to propei ly
changes no Jifrere"t from those pr~d~d by its i"cG",Gr~tion in the ethyl
ester. In the short-time slo~ga test, a ~l~slic-i~er co,)tent above 40%
procluces a Jisli".1 i"of~ase in viscosit~ after 10dl80~C while the slre"~l,s
on aluminium are at the level of a oonlacl aJhesive for a ~ -;-er oo, ll~l lt
of only 20%.
The methoxv ethvl ester shows very good pl~lic-i~ar coi"patibility in
regard to stability in slor~ya. The setting times on EPDM and limba are
acceptable up to 40% while the slr~"ytl, values are at the level of conldcl
adhesives above 20%.
Table 7: C~")~a, ison. T, iac~ti" Wlth and Wlthout 0.2% of PEG~00-Dimeth-
acrylate as Accelerator in Cyanoa~ylic Acid Ethyl Ester
CGmposition Stora~e Stability Settin~ rlme Sl.~n~tll
Tnacetin Acccle.dtor Vscosity Vscosity EPDM Limba Aluminium
mPas afler [s] [s] [Nlmmq
10d/80~C
10% - 131.3 423.0 12 55 19.3
25% ~ 183.0 487.4 17 ~60 15.3
1o% + 132.0 709.3 8 20 17.2
25% + 186.2 632.6 14 45 13 3
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H 1867 PCT 19
Res~ ~lts
- ~t~~ility in slura~ improved by ~--J-J~t;~ of an accelerator,
- s~Ui. ,~ times on limba accelerated by ~ tion of an A~lerator and
- st~ Jtl .s all at the same level.
The tests were based on the following ...eU.GJs;
1. Viscosi~y was determined as follows:
cone/plate measuring system, Visco~ity at 20 ~ 1~C.
10 2. The setting time of all the aJI ~esive ~."positions on the materials was
dete""ined as follows at 20~C t 1:
EP~M: A round solid rubber cord (dia",eter 13 mm) of
ethylene/propylene terpolymer (EPDM) was r,eshly cut. 1
to 2 drops of aJI ,esive were d~plieJ to the surface and the
ends of the rubber cord were i"""ed:~ely fitted toyell,er.
The setting time is the time elapsi"~ before the ~aterial
tears.
Aluminium: The time at which two freshly cleanecl and Lor,Jeul alu-
minium tubes (A = O.S cm') showed measurable resistance
to shiflil ,9 was determined.
Wood material: Pieces of limba measuring 100)~5x10 mm were over-
lappingly bor,J~cl. The time elapsing before early adhesion
occurred was the setting time.
2~ PVC: The time ela~si"y before two cle~ned (Jey,eased) PVC
strips (measuring 10~5~ mm) L,G"Jed with a 10 mm
overlap c~sed to aJl,er~ to one a"otl,er after breaking
apart at the bGIlJeJ surfaces was cJete""i"ed.
30 3. Tensile shear alle,lyU~s were Jele""i"cJ as follows:
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H 1867 PCT 20
The test spe~.,~- ,s measured 100~5x1.5 mm and were L~nJ~d over
an area of 250 mm2 with a 10 mm overlap. Aluminium plate was
deaned and sand~ the PVC was ll.e.~ly cleaned (cJey,eas6d).
Five bondin~s were carried out and the results were e~ressed as the
mean values. The test cor,JiliG"s were as follows: the tensile testiny
IlldChill~3 ope~led with a rate of advance of 10 mm/min. Curin~ took
place over a period of 6 days at 22~CI40% relative air humidity (air-
cor,Jition~J at."o~Jl,ere).
4. Shearrllllpacl alle~ was determined in a~cord~"ce with DIN 29653
at room temperature. The steel cubes were L orlJeJ over an area of
1 c~. ,
